[Restoration]- 1960's Multimeter! Sentinel ME-26D/U

hi everyone and welcome to another episode of mr. Carlson's lab today we're going to go through repair restore and align a very neat multimeter from way back when now this is no everyday average vacuum tube voltmeter this one's pretty special this is the military version of the hewlett packard 410 B and it has quite an AC range this will measure AC voltages in the frequency range of 10 Hertz to 700 megahertz it has a special probe with a vacuum tube right inside the probe I'll take the probe apart and we'll take a look at that little vacuum tube here quite shortly so we have quite a job ahead of us today so let's get started just before we get started I'll fill you in on a couple of neat segments hiding in this video that you're gonna find extremely interesting one of those things is pure proof that the Carlson low voltage leakage tester finds leaky capacitors where the high voltage leakage tester completely overlooks the problem I'll display the sensitivity of this device and the sensitivity of this device and will even read the voltage that both of these devices are putting across the device under test so that's some really neat stuff hiding in this video also as usual there's electronic trivia in this video if you want to increase your knowledge about electronic components hang around for that as well so lots and neat stuff I like to include electronic trivia in all the newer videos so you'll probably see that in most of the upcoming videos as well so anyways let's get started here's a closer look at the face of the multimeter the model number is M II - 26 D / u and this is made by sentinel electronics incorporated again very similar to the Hewlett Packard 4 10 B just this is the military version and it's more rugged the 410 B has a connector on the bottom where all the probes attach to and you can remove that connector as you can see here all the probes are fastened and soldered in place inside so everything is just much more rugged really tough looking meter it's an extremely nice condition this thing looks like you came right out of the box so this is a really nice candidate to go through and restore get working again so over here there's two probes one of them is actually an alligator clip which would attach to the chassis this is the common lead right here and this red lead is just for reading resistance this is just for ohms over here is a shielded cable that runs right up to this point right here so this is all shielded piece of coax and this is for reading direct current again this is a vacuum tube voltmeter so it's very very sensitive that's a really nice touch having a shielded cable all the way right up to this point here I'll talk a little bit more about these probes and how probes have changed over time some people may look at this program go whoa that looks kind of dangerous and by today's standards it might be but I'm not too worried about it I'm gonna be using this thing on the bench and we're gonna see this thing in action quite a bit in future videos so it should be a lot of fun to use this thing it's a very accurate device and over here we have a very interesting looking RF probe I think the engineers had a sense of humor when they designed this so there's a vacuum tube inside this thing and this is just a cap and in order to read the higher frequencies they actually suggest that you connect a capacitor to this into circuit I'll explain a little bit about that later on but that is the AC probe so this would be the common lead and you would use this to probe inside a circuit really big probe since there's a vacuum tube inside here I'm pretty sure that this is probably gonna get pretty warm we'll take a look at that vacuum tube in just a little bit as well so all the knobs here and all the switches they all feel you know like they're nice and positive the thing really just feels like a new unit everything is just you know the whole thing is just so clean and all the controls are very nice and tight on the face here so what I'm going to do is reposition the camera we'll take a closer look at the backside of this and we'll open the thing up change what needs to be changed make this thing work again and do an alignment this is the top of the unit right here see that says a nice rugged handle on the top little piece of rubber here so I imagine if it falls on the top it doesn't make a horrible racket kind of does anyways stop it from destroying the top of the unit I guess an axe is just a little bit of traction when you grab the thing as well let's take a look at the backside here you can hear that huh no easy that handle is when it moves around so this is on a soft rubber mat and I've got this placed on its face right now that's absolutely fine as this mat is really soft as you can see these little screws here you give them a half turn and they unlock so they're just uh kind of half turn fastener and this comes off and there's a place to store the cord in the back side these are all the adjustments for all the alignment so quite a few variable resistors there to adjust check the fuse as well make sure that the fuse is okay now you can see that there is a slot here to stick a screwdriver in so that we can turn the variable resistors but you can't turn the variable resistor unless you loosen this nut this is very much like the Chuck that you would find on a drill so as you tighten the Chuck on to the drill bit it basically it pinches down onto the drill bit well this is does the same thing what this does is this clamps the vrs shaft quite tight so that this can't move in transit so basically it's just a lock to stop anything from moving in a high vibration atmosphere something like that right so another very nice military touch to this so all of these have to be loosened off before any of these adjustments can be made and then once the adjustment is made you tighten this back up again and it holds everything right in place the cord itself looks to be in pretty nice condition yeah it's nice and soft very soft he's a little bit of cleaning up you know everything is really nice it's looking really good so the next thing I need to do to get into this unit here this handle is gonna want to go making a lot of noise again so the next thing I need to do to get into this unit is remove these screws have to remove this one here this one right here here here here all the way around so all the screws on the perimeter here there's two right here and there's also on the backside here again which I neglected to show there's the two screws that you see right here and right here and that should allow me to lift this case off here that'll get us inside so that we can take a look at the circuitry so that's what I'm going to do now I'll save you from all of that and I'll be right back once all the screws are removed all the screws are removed from the case so all I have to do now is lift this off look it's really no easy handle here it's catching on something hold that up like so see what's going on there it is move this out of the way pull it forward through the case here that down there and from what I can see it's looking extremely clean in here that's what I'll do so I'll just zoom on in a little bit lots of nice shiny allen-bradley resistors I'm pretty sure they're all going to be okay some nice high accuracy resistors over here disc capacitors that's nice to see in an application like this no waxes or anything like that you can tell they've learned through the lessons those things over time filter capacitor yeah and let's see if the tubes no it just says V 5 and V 4 so we'll take a look at the schematic here in just a little bit in order to get these tube shields off what you do is you push down and give them a twist and then just come off like so a little spring in the top here to hold the tube in place so that's a 6 X 4 which means that that is a rectifier tube so that's going to take the transformer here the B plus side all right that's going to take that take the alternating current change that to DC and then this thing here is going to filter that so that's what that tube is there everything is so nice and clean in this thing see what's under here that would be a regulator tube of some sort so what I'll do I'll put this down here like so and I'll remove this tube so what I'm going to do is I'm going to gently rock this back and forth and what I'm going to do is hold this down here and I'm gonna apply up force like this now by me holding this and applying up force when this comes out of the socket it's not going to go flying cuz usually what happens is these tube sockets are so tight they just pop out and then you end up tossing a tube or something like that so you don't want to do that so what I do is I just hold it here apply up force and then gently rock this like so and it just comes out nice and safe like that something you're gonna want to keep in mind they say pull directly up on the tube no Rocking I would suggest just a very slight amount that'll help ease this out of the socket I'll tell you why here in a moment that they don't want you to rock any tubes and I'll give you an example of that as long as you're careful and you're not doing this with the tube you're fine just gently like so as you're pulling up and it's absolutely fine again I get this question a lot in a lot of videos is it okay to touch the glass on a tube it's absolutely fine to touch the glass it's just standard glass there's nothing special about it so the number of this tube is zero B to W a so this is a regulator tube this one will glow orange many regulator tubes glow kind of a powdery blue color this one will glow a nice neon orange color and we'll also take a look at that here in just a little bit so nice regulator tube so it says Jam je n means joint Army and Navy so and then there's a number down there's a little bit smeared it looks like at the bottom so zero it doesn't have a filament zero and then zero volts on the filament B factory indication number two two useful elements inside this vacuum tube so cathode and plate W a just means that it's an industrial-style tube that's what all that stuff means so because I can't see down in the socket unless I hold this like so you gotta look for the opening the index here and then put it down in there like so and then just give it a bit of a push and it'll go right back in and I'll put the shield back on this one here and just push down so and then up locks into place so this looks like the only filter capacitor in this thing so this one is the reason that I want to open this thing up really even though this filter capacitor probably has very low time on it and it's brand-new since this is gonna be a permanent part of the bench here and we're gonna be using this for testing many different things I want to make sure that I got a brand new dependable capacitor in here because these things here when they're old like this they can just go at any time and I always like to say this I use this as an example is you turn the thing on let it warm up cuz you always let these things warm up for a little bit of time before you start using them right you go get yourself a cup of coffee and when you come back their room is filled with smoke and it's pouring out of the vents on the side because you didn't change your filter capacitor people say oh it's okay to reform these things well if you want to take the risk in you know lose a power transform or something like that yeah and by all means go ahead and reform your capacitors caps are so cheap nowadays why would you waste your time don't reform the old capacitors they're out of there get rid of them there's no point I can test this thing when I can pass it or tester and it might show good but you don't know what's really going on inside this thing then either this thing has been you know sitting here for years years and years and years since the 60s so you know just a good idea to get that out even if this thing has been replaced you know who knows how long this thing has been in here for a couple of bucks for a capacitor why risk this beautiful great block right in the center known as the power transformer just not worth it on this site here this is a ballast tube what the ballast tubes do I'll zoom into this here all right let's take a closer look so you can see a little filament inside they're strung inside this tube it looks like you could almost be a light bulb right well that's an iron filament in most cases there are iron filaments and they fill the glass here with either hydrogen or helium and this is known as automatic current regulator now most likely in most of these these types of VT VMs or whatever like them the old HP 410 B this is used as a current regulator for the filaments in the little tube inside this so they're regulating the voltage right to the filaments right here so really what this thing does is it just maintains a constant current with varying voltage all right so if the line voltage changes or there's any excursions this you can look at as an AC regulator it's really what it is really neat devices now these things have got some pretty tight parameters with them and this one here is a and that one would be a 6-4 ampere right nice looking tube well take a look at the filament in here now when these things are in service they should never glow bright if these things are glowing very bright you have a problem in the circuit and chances are you gonna burn out the ballast you got to be very careful with that you never want to see these things glow bright you want to see just a little bit of a faint orange glow in there sometimes one portion of the filament will glow a little bit brighter than the rest again as long as this just a faint orange glow no problems if the thing is glowing like a lightbulb or something like that the thing is gonna go that means if there's a short so that would mean that the filament line in here has a short or something like that maybe the tube itself would be shorted in this probe here looks like the probe has a crack up there most likely what somebody has is you can see how there's a little bit of a thread inside there so there's a probe piece that would thread into the end of this and somebody's probably dropped it on the floor and what it's done is it's put a crack here and looks like somebody's put some superglue or something on that because it's pretty solid so I'll have to make something to put in the end here to test this thing out so that you know when we do the alignment with the AC we can actually align it properly so I imagine we be holding onto this thing for a while and this is gonna be a part of the the bench here that's what I might do is just fill this with superglue and then sand it down I might even primer this and put a nice coat of paint over top of it and you'd never see that crack just be completely gone so and in a moment here we'll take a look at the vacuum tube that should be hiding in here so I have to remove these two screws right here let's take a look at the rest of this first here so there's two other tubes here as well marked what is this v2 and v3 let's see what they are okay a double triode of some sort what does it say the numbers of course oh it's a sixty-one 89 there it is it's a 61 89 right here and this one is another 16 189 and they all look so nice it doesn't even look like they've ever been touched or anything like that and you can notice it's both of these tubes they've got the same writing on them so chances are these are factory you know I'm thinking that they are very nice so what I'll do now is we'll take a look at that tube inside the probe let's move that out of the way all this stuff out of here like so and I'll zoom on in again okay screwdriver where did I put that thing another one I'll be shoved off to the side here and okay and there it is a little tube inside there so I'll very carefully remove this from the top holding the tube in so what I'm going to do is so I don't pull the tube oh I'm just going to hold the tube in here and when it very carefully remove this connection just put it off to the side like so and I'll remove the tube and there it is little iMac tube right there so one connection here one connection here and one connection here you'll notice in the bottom there's a pinch seal on the bottom of the tube you want to line that pinch seal up then when you're putting this thing back in it should just very gently push into place like so and I mean very gently that just slides right in there and then this also has to be put back on very gently I'll do that off of camera so that way I don't hurt the little tube these tubes are pretty fragile you wouldn't want to be causing any damage to these things I do have spare probes and spare tubes around but I'm hoping that this tube is good again I haven't turned this thing on because I don't want to take any chances I just want to get rid of that filter capacitor and that way we can start with a fresh alignment on this thing and make the thing work the way that it was intended to work right in the beginning so what I'll do is I get this thing put back together here and we'll take a closer look at that filter capacitor here in just a moment and I'll tell you what I'm going to do to replace that thing I was going to mention why they don't need a rock the tubes so what I'll do is off just put my finger under here just on the lip here and I'm just going to move this back and forth so I can get this out these really do need some up force in order to get them out so you can see that how I'm rocking this tube here just gently and there's a real good reason for that so my finger under here again this is extremely tight so I imagine that these tubes are probably all original see how easily that comes out on the bottom of this tube here is an index you see this index pin right here what ends up happening if you rock these things too much you break the index pin off an exhaust tip for the tube is underneath here as well so that's where they evacuate the tube right in this little area so when they put this socket on the pins stick through and then they solder them up here and that little exhaust tip is usually in this so if you sometimes if you break this off you'll also break the exhaust tip off as well and if you can see it in the bottom there it's a little pipe that usually sticks out of the bottom yeah you can see it right there if you look carefully you'll see how that runs straight down right and that runs up to that little hole right there which allows them to either fill it with gas or pull vacuum so that's one of the reason they don't want you to rock these things so you got to be very careful again getting these tubes out by just pulling them straight up it's pretty much impossible unless you've got something under there that you're prying up with so that alone can damage a tube so what i'm doing here actually i'll tell you what i'm doing here is i'm i'm just turning this you can see this this is a lock on it right this is index tee little index there so if you don't know where it is what you do is you can just sit it on the top of the socket like this see i'm rotating this so what I'm gonna do is I'm just gonna rotate this with my finger and it'll fall in place once it finds that little part of the socket that fit that it mates with see that just falls right in then I can do is just very carefully slightly rock it into place as well so just like so and this is extremely tight I'm putting a lot of downforce on this right now so these sockets are nice and fresh again don't worry about you know leaving a fingerprint or something on a tube other than you know aesthetics wipe it off it's not a big deal and this just standard glass it's nothing too incredibly special one thing I should mention is vacuum tubes get extremely hot when they're in service so you don't ever want to touch a vacuum tube when it's hot because you can really burn yourself bad power tubes audio output tubes things like that they get extremely hot like to the point of where you can melt plastic on them so you got to be very very careful a lot of the times the basis of these tubes are made out of bakelite so no problems there but yeah you don't definitely want ever touch a hot tube and in a case like this let's zoom out here in a case like this this does have a filter capacitor in here let's turn this over here and this is what we're gonna look at in just a moment this has a filter capacitor and this can store a charge for a very long time which can be very dangerous considering that this is going to be you know charged to a higher voltage right so the transformer creates you know usually a step-up effect depending on what type of you know circuit this is in so it's probably stepping this up you know that you an elevated B plus let's look at it like that alright so it's going to you know step up the AC this is going to rectify that so it's gonna change it to direct current and this is gonna be the filter so this acts kind of like a battery and if there's nothing in here that say there's a fault in the circuit nothing's gonna drain this thing off this can stay charged up like a battery you can get a really really bad shock in something like this so you got to be very very careful all the caps need to be discharged correctly before working on something like this so if you're following along and you're working on something like this you're doing so at your own risk if you don't know enough about these circuits to know that there is a you know a charge that could be left on this you probably shouldn't be working on something like this the capacitor at this point is still held in and this is a really good time to get rid of the connections once the capacitor is loose fumbling with the connections and removing solder and things like that becomes a bit of a pain so while it's still held in place what I want to do is remove the wires here so you can see what they've done is they folded the wire over the terminal here sometimes known as an ear what I want to do is I want to clip this little area off here very carefully by clipping the fold off when I just put my soldering iron on here the wire should just come right out so what I want to do is get a really sharp pair of wire Clippers what I'm going to do is just put this down so I can do this very safely so put this here it's always a good idea to wear eye protection as well when you're doing this I like to cover these up so what ends up happening is sometimes they end up flying off now you can see right there that I've taken the top right off and I have hurt the terminal so all diesel zoom on in just a little bit here I haven't hurt the terminal but you can clearly see where the wires have been cut on each side and that's very easily done just by looking at the actual area and then just giving it a clip until you feel the resistance of the actual pin in the middle so looking at this one here I'll see if I can get this on camera it's kind of tough with everything in the way so what I'll do is get that down there like so so you want to get it on just just on each side there I can't really see the depth here because I'm doing this on a monitor so right about let's see here about there okay and then what you do is you just give it a bit of a pinch like so and you see that look at that the terminal itself isn't hurt at all but you can see the bare copper on each side now when I heat that up what this is going to do is just come right off this is a nice easy technique if you don't have a de soldiering tool so now put this here and I do have some resistors in the way so what I'm going to do is just grab this with a plier use this one here I'll heat this up with a soldering iron depending on the solder sometimes it's beneficial to actually add some solder that way it melts just a little bit easier does I'll just add a bit of solder to each of these here and it'll add a little bit of solder to this other side right here thanks so ok so now that out of the way this well first of all I'll grab this gray wire right here it's kind of in place by that resistor on with my arm around here like so grab this like so and you can see how easily that comes out just like so that one's out the gray wire is off you can see right here and go down here to the orange one it's like so and then this one over here there it is and just like that all the wires are disconnected now if you're unsure C D soldered all these wires and you're thinking to yourself oh I don't remember where they went you can follow the schematic to figure it out or if you like the thing that I do a lot is if there's a huge area and Sam dis all during you know there's a whole bunch of wires like this and say you D soldered all of these wires just for example or something like that you want to know that you're putting them right back into the same spot it's always a good idea just to snap a picture that way you see you have your phone just snap the picture click and then that way when you're putting it back - you can go oh okay the gray one right here not here right just to make things simpler something like this you know is only you know what maybe three connections on this one and what two connections on this one so it's absolutely fine not too worried about that so this one here these two and this one run off to look what would be the negative side here another thing that you can do if you say you're gonna be working on this thing it gets late at night or something like that and you end up getting tired and I you know we want to finish this off the next day we can do is just put a little tack of solder on these like so so what you do is you would just take all three of these and then tack them together all right so do this and then tack them all together and that way you know that all three of these wires go to one connection the next day and then you would if this one was D soldered as well what you would do is tack this one to this one and you would know it was deposit very easy to remember this red wire red terminal here and everything would be fine so just a few little tricks to help you through when you're working on this kind of stuff these believe it or not these small things mean a lot I removed the capacitor on the top side of the chassis move some of the wiring around on these resistors that allowed me to mount the new capacitor below these two resistors and use the two terminals on the resistors as a tie point now there are a bunch of bonuses here by doing this so number one there's a nice big hole here now and that allows for a thing called convection cooling what is convection cooling you ask well heat rises since this is on the bottom portion of the chassis what that's going to do is as these things are getting hot and the hot air is rising it pulls cold air in from the bottom and creates a cooling effect the capacitor is below these resistors so as the heat is rising this is staying in a nice cool area now the leads look a little shorter than they actually are just on camera here but there is enough lead on this capacitor to act as a thing called thermal decoupling so it's not too close that the heat of these terminals will affect the capacitor again heat rises this capacitor is rated at 105 degrees C and this is a very high quality capacitor and it has a really high hour count on it too so these lasts for a very very long time this is a high quality Rubicon type capacitor and I suspect that this will last an extremely long time I don't think I'll ever replace that again so everything worked out really well I'm quite impressed with that install there another thing that tells me that these resistors don't really get all that incredibly hot is you see how this insulation on this wire runs right up to this terminal here normally when resistors like this get incredibly hot it discolors the insulation down the wire aways and a lot of the times it'll even chip right off you can see the insulation here is fresh right up to where they've been soldered on to this terminal right here you'll see this resistor here is very close to this terminal tie board right here you can see the nice shine on the tie board and there is no discoloration when these things get very very hot it takes that shine away and it turns this into a very dark color on this board right here so since this is a military unit everything is really overrated so I imagine that these things may get warm but not incredibly hot so everything worked out very well with this install so at this point pretty much ready to try this thing out and see if it works first though let's take a look at the old capacitor this is the original capacitor out of the unit and just looking at it like this it looks to be pretty nice only slide this down here we can see that it was made the 12th month of 1966 pretty much seen 1967 at that point it looks nice general instruments now if we take a very close look at the bottom here I'll just move some of the lighting around look what's happening so we see corrosion on the bottom portion there and that's most likely because this is leaking physically leaking at this point now we wouldn't normally see that because this clip is on here and it's tightened in here like this so everything looks fine like that but we can see that it's already starting to break down now that doesn't necessarily mean that the capacitor won't function for a while so what I'll do is I'll turn this on here is get the light out of the way so doesn't glare on that so we'll test this for leakage and we'll see if it's okay this right here that's discharge and that's test it'll take a few moments here and as you can see it's testing really nice for a leakage no problem there we can see if it's holding a charge when I click this on to discharge you'll see this light up and then slowly fade out that's indicating the charge on this capacitor it's actually draining it there you go so it's holding a charge no problems so what we'll do is I'll test this for capacitance now over here so this capacitor here is 12 micro farad see that they're rated at 450 volts the replacement component that's been put in there is 22 micro farad at 450 volts so there's a little bit more capacitance a little bit of extra filtering and that's absolutely fine in that bt vm or multimeter okay and as you can see no problems with capacitance a little bit of an overachiever there 14.5 and as we saw on this device here the leakage is fine so it definitely is an overachiever so there's no problems if I go and test this for ESR just through these two tests I can pretty much tell that this is going to be fine now getting my gen rad into the shot is going to be kind of tough or my ESI video bridge so what I'll do is I'll just use this for a quick test right here I'll turn this on and I'll have to shut off some of the lights here so that we can see this all zero this out what I'll do is I'll just put this right across these two terminals here so I'll just zero this like so short a screwdriver across here all right if I can get this to make good connection doesn't want to make good connection does that okay there we go okay so let's see what this says 0.67 so no problems with ESR so we can see 10 micro farad right we can see rate up here at 250 volts is 2.5 that's allowed to be so that's doing just fine point six seven no issues whatsoever especially for the age of that capacitor so what does all of that tell us that tells us that this capacitor here would work in that circuit but for how long no one knows now we can already see let's turn the lights on here again we can all see the signs of leakage the case of this is corroding because this is leaking past the seal here so it really only is a matter of time and as I say these capacitors here they go just whenever there is no set time there's no real way of telling it's just you go get your coffee come back in the power transformer in the device is ruined so for the price of a new capacitor as I said before it's just not worth taking the chance get rid of this thing let's mean in 1966 well we could say 1967 you know it's definitely gotta go just before I go about powering this up and attaching this to my current limited isolation transformer and variac supply I want to make sure that the fuse hasn't been tampered with in this so fuse is marked f1 and if we look on the sheet here f1 is rated at 1.5 amps so that's what I want to check and there it is I can get that into the shot so you can see that one Seattle one right there one and 1/2 amps so the fuse is good and it doesn't look like there's any issues with it looks solid still so this is all a good sign nothing major has really happened with this unless of course somebody is played with this in the meanwhile and blew the fuse and put a brand new one in we'll end up finding out if there's any issues with this here in just a moment when I attach this to that isolation transformer and current limited very ex-employee one other thing that I've noticed here is here's the line cord coming in and there's two disc capacitors that are attached to the line cord you can see these two disc capacitors right here now these are not X 1 Y 2 capacitors what I'm going to do is replace these with modern safety components as well and I'll do that right now just before I go about powering this thing up these 2 capacitors have been removed from circuit now so these are both point 0 1 micro farad you can see that right here 103 and the appropriate safety components have been installed so these are X 1 Y 2 rated capacitors and these are SPECT to be across the line cord and from the line to the chassis so whenever you're working on anything like this that has these older disc style capacitors that don't have the appropriate safety ratings it's always a really good idea to get rid of these things and put in the proper updated components I have this multimeter attached to my isolation transformer and current limited variac supply so this is plugged into that right now and I'm about to turn this thing on to see if we can get any life out of this thing what do you think is gonna happen I'll turn it on to the negative DC volt range first let's see what happens that's a good sign the indicator light is nice and bright if this came on very dim I would shut this off and I would suspect that there might be a problem with heater circuit the fact that the meter is working like that and that's perfectly fine right now the fact that it's moving like that tells me that the B+ section in here is working as well so two very good signs all from just clicking a switch on and looking at the indicator light and what I'm seeing on the meter so the first thing I'm going to want to do is zero this out so what I'll do is I'll grab the common lead in this case it would be negative attach it to the DC probe and I want to adjust the zero adjust here so let's see if I can get this to zero no problems it's zeroing now here's the thing this needs to warm up for about ten to fifteen minutes this is just a quick test to see if the thing is working so whenever you have a meter like this thing you turn it on you go grab your coffee let the thing warm up let the temperature stabilize inside and then it's ready to to go you can see that the needle is going to wander here a little bit until the thing warms up so what I'll do now is this is on the 10 volt scale so I'll turn on my power supply here and they happen to be set really close to three volts so what I'll do is I'll just move this down to 3 volts here and I'll see you can see that thing yeah probe is working which is a good sign just make sure that zeroed again let's see how close to negative 3 volts this will reduce all attach this to common that just happens to be the top of the scale as well so here we go not bad look at that right there very very close so what I'm gonna do now is test the positive so let's see what this does I'll feed this with positive 3 volts right now I'm just touching this s why it's doing that so here we go and yeah it could use an alignment but it's working that's the main thing make you care less about the alignment right now I just want to see if the thing works and it's doing well so that's a good sign so let's test the AEC so now since this thing since this thing here has no probe tip on it this isn't gonna reach around the top what I'm gonna do is just zero this out see if I can zero that out it does zero another good sign and I'm just going to inject a signal into here without touching it so I'm going to use the non contact signal injection probe that I've released on patron so what I'll do is I'll just turn this thing on like so and the whole idea of this thing here's the probe right here it's attached to it so what this thing does is it'll inject a signal into a circuit without even being connected to it so to give you an example look at this there's no connection there whatsoever I'm just bringing this close to it so I designed this thing for audio signal tracing for RF signal tracing and for signal tracing problems in AF sections so you can kind of look at this thing almost is the opposite of the super probe so the super probe sniffs out a signal this thing injects the signal so if you're working on an audio amplifier and you want to find out where the signals gone missing you just move this thing around in the audio amplifier and this thing will inject a signal directly into components with no contact that's why it's called the non contact signal injection probe so all the plans to build this are all up on patreon as you can see I'm trying to make this as universal as possible so this is a desalter in pump shell so I'm trying to use all Universal components and make this thing as easy to build as possible so right now this is just on signal if I go up here so this is the amplitude control here if I go up here this will actually inject a tone in this mode right here if I turn this up to high this goes red and it tells me to turn it down again it's also a way to test the battery so so there's either a signal with no tone or a signal with a tone and again you just adjust this until that would be the maximum that you want to turn it up and then you turn down and then you're ready to go just move this thing around in circuit and you can inject a signal so no problems there if I turn this up to the 10 volt range let's see here and get an idea of how potent this little thing is so that's on the 10 volt range right now look at that so lots of signal coming out of this device really neat little thing I'm going to do some videos troubleshooting with this little device as well lots of people have built this up on patreon and they're very happy with it by the way lots and lots of projects up there for you to build this is just another one of these neat little projects that I've created and then I'm sharing with the community and it's the same thing with this capacitor tester as well all the plans for this leakage tester are up there circuit board layouts everything is sized all the instructions to put it together alignment procedures schematics everything for all this stuff is up there so feel free to go up there and check that stuff out so so far all the ranges are working up to EC what I'm going to do now is go to the ohms range and what I'll do is I'll grab the this one here is the probe for ohms so what I want to do is short this out and see what happens it does go to the zero that is a very good sign and then for the ohms adjust I need to adjust this rate till it goes right to the number one there so I need to adjust this for maximum scale right so rate till it's at the 500 and read it the one for maximum right there so that's maximum scale so now I don't if you can see the shadow it's right over the last little bar on the ohm scale right there it's easier to use this because it's easier to see rate at the top so now what I want to do is I want to test a resistor and see if this is going to read correctly so here's a shortcut in order to use this the bottom scale here is the ohm scale alright so if this is on our x one right here you have to readjust this when you switch ranges by the way a lot of the times so this says R times 1 so that's 0 to 500 ohms so you can see R times 10 what you do is you take that zero and put it at the end of the 500 so now we have 5000 so that's 0 to 5000 ohms now you see there's two zeros here R times 100 take those two zeros and put it up to the top here so now we have 0 to 50 thousand ohms that's how you that's the shortcut for this so I want to go up to here to this scale right here which is R is one case so that's three zeroes so that's zero to five hundred thousand ohms okay so that'll be 1 K 2 K 3 K 4 5 10k and then that line there should be 15 K right there just below the 20 okay on this scale again I'll just adjust this here the ohms adjust just to make sure it's perfect and let's find out how close this is okay what do you think no alignments nothing has been done to this thing as you see it is as it's come I haven't touched anything on the back I'm really quite surprised with this thing already so it should go if it's are gonna read correct it should go right to that line right there or very close to so here we go look at that no alignment at all you know close that is right there very impressive so so far so good so now this thing just needs an all-around alignment to get it as close as possible so what I'm going to do is get the manual and we'll go through the entire alignment procedure and make this thing work as good as it can I'm ready to perform the alignment procedure on this multimeter now but there are a bunch of steps that I need to take that are absolutely crucial before I start in order for my alignment to be as accurate as it can be these are steps that aren't normally talked about so if you're interested in doing alignment procedures on many different types of electrical apparatus you might want to get a pen and a piece of paper and take down some notes again these are very important steps to take the very first thing I need to do with this thing before I go about starting the alignment procedure is with this thing completely unplugged so no power applied and this thing is in its normal operating position so the face is straight up and down I need to adjust the mechanical zero on this meter if this isn't done your entire alignment procedure will be off because the electrical zero here will be fighting the mechanical zero so I'll turn on the light here that's the little adjustment that needs to be made with this unit off something to keep in mind that a lot of people don't think about when they're doing this is you can't have this thing tipped on its back when you're aligning this thing because there's a counterbalance on this needle that sits right down here that counterbalance won't be affected by gravity the same way when this thing is sitting flat like this so if this thing was sitting like flat like that right there so what'll end up happening is you'll set your zero adjust with this thing like this but when it goes into its normal operating position again you'll have to readjust this to the zero and that can affect your alignment so always keep that in mind the trick to remember is whenever you're aligning something you want it to be as close to its normal operating condition as possible when the alignment is performed so for example when I do the final alignment on this thing which will be off-camera because it just has to be right now this is open so I can show you what I'm doing when this thing is off-camera this thing will be in its case because in order for this thing to heat up properly right now this thing is you know it's letting all the heat off right it's not up to its normal operating temperature and it really won't get up to its normal operating temperature unless it's in a case so this has to be in its case and it has to be sitting straight up and down I'll let the thing warm up for about a half an hour or something like that before I perform this procedure again so that this thing is you know really nice and hot like it normally would be sitting you got to remember there's a bunch of tubes in here in a transformer and a whole bunch of resistors and components that are letting heat off and right now it's just venting there's you know it's not holding it in to that that case like it normally would be now you have to remember that heat affects your alignment big time so what happens if with heat is it causes components to expand so heat is your enemy whenever you're doing any type of alignment any type of temperature variation I should say is your enemy so again you want this thing as stable as possible so it's warmed-up you know it's in the environment that it's going to be in and then at that point you do your alignment in that way your alignment will be is accurate as it can be you got to remember the results that you're reading on this meter when you're using this thing as a piece of test gear are only is accurate as your initial alignment the initial alignment is out everything else is out that's why alignments are so incredibly important on pieces of test gear and this is the reason that metrology labs and things like that are so incredibly expensive because a lot of time is put into this the reason that you don't see a whole lot of analog meters like this anymore is because this thing is incredibly expensive to build this is a very accurate device you got to look at it like this it's taking electricity and turning it into an analog reading here so this has to be very very accurate and in order to make the ohm scale accurate you'll see how little areas are pinched together between the numbers and then some of them are wider and then a pinch together and that's just because of the characteristics of the meter it has to be like that in order for this thing to work correctly so lots and lots of time is put into designing something like this and this is the reason that digital meters nowadays are so common because they're a lot while they're a lot more cost effective to put together and to put into production right building something like this right now it would be incredibly expensive in this day and age right so those are some things to remember now here's another thing to remember when you're performing in alignment say you perform your alignment you're getting you'll say 3/4 of the way through your alignment and then you test something and the meter isn't reading correctly so there's a component inside that isn't working correctly something is off value right for example earlier when we tested this on the three volt scale the needle sat over here so say you get three quarters to your alignment you get to that point and then you find that you can't align it guess what your entire alignment is null and void you got to go in there and fix the problem come back and start right from the beginning and do the entire alignment all over again because changing that component that one component can affect multiple things not only that you're moving things around is you're changing things wires are getting shifted this is very important in oscillator circuits and things like that on circuit boards and even just point-to-point wiring moving components around in an oscillator circuit and a freerunning oscillator circuit will completely affect an alignment so all things to keep in mind again in order to do this alignment and habit is accurate as possible what do you need to remember this thing needs to be as close to its normal operating condition as possible before the alignment is performed that's why I'm showing you this on camera right now so I have to do this open but in the end I'll let this thing warm up in its case and it'll be sitting straight up and down and then this will get performed all over again when you're aligning this needle right on to the zero mark you also want to look at it square on you don't want to look at it from the side or anything like that it has to be straight on you want that as close to being right on top of that line as possible again this will affect your alignment now when we're doing the alignment all adjust this to the zero it may look a little off on the camera just because of the angle in the camera looking at this right now this here is the maximum angle I can put this on that just happens to be the height of this roll of solder this is the maximum height that I can have this the maximum angle I should say that I can have this meter on right now before the needle will Coast off the zero mark because I'm you know tipping this on its back and that counterbalance isn't being affected by gravity the way that it normally would be so again things to keep in mind right so we're just about ready to get going right here I've already zeroed the meter so with the power no often there's nothing applied to this thing I've zeroed the meter and that was with it straight up and down and then I tilted it back to the point to where the needle started to coast off the zero and then I brought it back up ways so that way when I'm doing the alignment it'll be very close here as I'm showing this to you so again if I'm start on the alignment we get to that three volts scale again and say it's off on the three and we've done the the 1 volt alignment on this thing guess what we got to go in there and find a problem and start all over again that's just how it goes with alignment procedures so I'll get the manual let's get going the first thing I need to do before I start in the alignment procedure is loosen up all the retaining nuts on all the VRS on the backside here this is all the alignment points right here that's very easily done with a half inch wrench now already pre loosened all of these off they're usually just snug and these ones work the very first alignment point is this one right here this is the DC calibration see that right there words of gold once the adjustment is made tighten the retaining nut up before you move on to the next stage once you make the next adjustment tighten that retaining knot up and move on to the next one it's very easy once you're adjusting all these things to accidentally put the screwdriver into something you've already adjusted and twisted and depending on what you're aligning that will cause you in some cases to have to redo the entire alignment and when that happens usually at that point you just walk away for a while and come on back so some receivers have rows and rows or banks and banks of tunable coils and capacitors and they all have to be aligned in a certain order so if you accidentally go to the wrong area and twist something you have to start the entire alignment right from the beginning to get the highest amount of accuracy and again usually when that happens you just you know go grab a coffee or something like that come on back so moving the signal generator around from frequency to frequency and changing amplitude and all that kind of stuff with every single adjustment especially in receivers is quite a job quite an alignment procedure at any rate so back to this thing let's take a look at the alignment procedure so what's up here is a lot of the stuff that we've already talked about some of its common sense remove the rear access cover things like that because you can't twist those controls without it now this is most likely designed to be aligned in the field that's why they say allow the multimeter to warm up for at least five minutes at least five minutes again you want this thing as close to operating temperature as possible so I say half an hour is a nice a nice time I have some pieces of test equipment that's specify twelve hours of warm-up time before any alignment is done so it just depends on the device so half an hour is a nice I would say kind of average for most pieces of tube gear before you're doing any type of alignment again everything needs to get right up to that operating temperature for it to be as accurate as possible so we'll start here it says alignment of the one bolt range is the only DC voltage alignment required when the one volt range is aligned all other ranges fall within permissible tolerances to align the DC function of the multimeter proceed as follows selector switch to positive so you can see down here it's already set to positive set the range switch to one volt already done pointing at one that would be three that's one connect the common clip to the DC probe the reason they want you to do that is to keep noise out of this while you make the next adjustment so this out of the way so it's not so bright is here so adjust the zero adjust control until ammeter m1 indicates zero so of course this is the electrical adjustment keep in mind that the adjustment the mechanical adjustment has already been made before this whole thing has even been powered up right again you don't want them to fight each other so to me this is square on so it's gonna look a little off in the camera but there is it but right on top of that line so that's about as close as it gets connect the common clip to the common connector on the meter tester and connect the DC probe to the 1 volt jack so basically all you're doing is you're connecting this to a high accuracy 1 volt supply now when I say high accuracy I'm talking about a couple of zeros what I've got here is more than that's needed so that's very close the power supply just happen to land on that so I left it right there that is over enough zeros so we'll connect the common or negative it could be called because this is the you know this is a DC measurement and this lead here is connected to the same area that positive probe is and it is very close it is very very close so what we'll do is I'll just put an adjustment in here and try and get it as close as possible so since I'm trying to find that little adjustment here I'm not looking at it I'm just kind of feeling around the backside here yeah there it is okay so now if I twist this you'll see that I can really move this around all right so what I'll do is I will bring this below and then I'll bring it up to the one that's right on top of it okay so that's right on top of that one right now now if you recall earlier when we tested the three volt area it was way over the top now if we do that right now or reezy row the meter if it's above the three the alignment procedure stops and we go looking for faulty components now all right so what I'll do is I'll disconnect this and I'll put this onto the three volt range I'm going to our easy row the meter again so I'll just unclip this put this onto here and that is the ohms a Jess I want to do this one right here there we go yeah okay there it is I would say close enough connect this back up to here what I'm going to do is adjust the power supply for three volts so I wanna move this up to three get it as close as I can to three okay so there it is close enough okay now connect this back up and hopefully it lands right on that three if it's above it like it was before alignment procedure ended troubleshooting commences okay so here we go what do you think let's start troubleshooting okay let's see what we're up against so this is the DC voltage measurement circuit in here this is the DC probe so right away we have a 22 Meg resistor which we should check and then of course it goes into this resistor stack right here which is on this wafer switch right here so really all of these resistors at this point are suspect so that's what we're gonna check check this one here first and then move our way down here unfortunately I'll have to desalter one end of the resistors to be checked so that will be a little bit time-consuming take a look at this here so this is the probe so if I open this up like so and unthread and at least it's cooperating a little there should be a 22 Meg resistor hiding in here somewhere oh look at that there it is okay let's see what this measures I'll put this up here so it's InFocus okay what do you think let's measure it place your bets now that's quite a ways off from 22 Meg's it's almost 26 Meg's there that is an awfully small resistor I think this scale goes to a thousand volts so there's a problem right there and the next thing to do would be to open the resistors on here I'll open some of the larger ones at the top we'll check them out and maybe some of the lower resistances we can just check in circuit and I'll see how close they are so I'll get this changed on to this the new 22 Meg resistor is installed and as you can see I've shortened up the lead length quite a bit just because there's no need to have all of that exposed lead here they have shielding on this cable for a reason and that's to keep noise out of the circuit so with all of that exposed lead length if you're holding this up close to the tip and this is exposed all the way up to this point here there's a really good chance that you're gonna add noise into the circuit so I wanted to shorten that up as much as possible and this worked out very very well so there's a lot of lead on this that's soldered right down into here and then that's just wrapped around here and there's a bit of heat shrink tubing over the shielding the shielding ends right here and then this is all just the center conductor the resistor itself is very close to twenty two Meg's I spent quite a while grading resistors just to make it as accurate as I can so that worked out very well so what I'm gonna do now is put this pearl back together and then we're going to focus on these things right here these big resistors okay I've removed one end of both of these resistors here and let's see how close they are so this one is supposed to be six point eight four Meg's and this is supposed to be within 1% of that so let's find out I'll attach this end here and this end here and let's find out six point nine oh seven that's got to be pretty close to the end so let's find out so Claire so what we'll do here is we'll go six point eight four plus one percent six point nine zero eight I'll talk about being close to its maximum and holding it that's almost like that's like lottery numbers right there let's say 2908 and I went to six point nine zero nine fail so that's gone so I'll have to make a resistor out of a bunch of resistors to get this value so let's test the next one here the next one over you get the clip on this one is two or twenty one point six Meg's this one here they've got the value on the other side you know the person that put this together put most of the values facing in to the selector switch when you're putting something like this together you have the values right where you can read them so I moved a bunch of these around so that we can see the values talk about crazy Wow so it's to be twenty one point six not twenty two point six that's one Meg high so let's go twenty one point six plus one percent twenty one point eight that's way out of there so that needs to go as well so I can see this meter getting a whole lot more accurate so I'm gonna keep going through this whole area in checking all the resistors and the ones that need to get replaced will get replaced I'll get on that and we'll get back to the alignment lots of new custom mr. Carlson's lab resistors installed so all these resistors here I've created the the values of these resistors when they were brand new so these are all graded and extremely close to their values so this is 20 1.6 Meg 6.8 for Meg 680 for K 216 K and there's another 2 on the other side there's another 20 1.6 Meg resistor on the other side and there is a 46.7 Meg resistor on the other side as well to replace all these ones here that you see down on the mat so lots of resistors on this switch that needed to get replaced because they were really close to the end of their tolerance so let's see how close the voltage reads corresponds to the meter on the face here let's take a look at the accuracy of this meter now that all of those resistors are changed so I've already gone through the first steps of the alignment like we did just before so you don't have to go through that again on video so I'll just show you that the meter is zeroed on the 1 volt scale here so I'll just ground the probe out and that's right on the zero mark the power supply is set to 1 volt so I'll show you that right now very very close so we'll check the accuracy of the 1 volt scale and as you can see that spot on no problems there whatsoever so now I'm going to do is turn the power supply up to 3 volts and this will be the moment of truth I'll just turn this right up to 3 this as close as I can very touchy control very touchy trying to get this as close to three as possible okay so that's close enough no problems there three volts on the three volts keel I'll just check the zero and it's very close here we go that's a spot on the three so what I'll do is I'll just move this very carefully hopefully it the meter will behave spot-on no problems so that portion of the alignment is successful thankfully here's a much better example of the accuracy of this meter now I managed to get the camera more focal onto the meter right now and everything is nice and steady so check out that accuracy it's right on top of the three and right at three volts so those new resistors made a big big difference I'm very happy with the result so now on to the rest of the alignment procedure the next portion of the alignment procedure involves setting filament voltage of the little tube inside this probe here so let's take a look at what they tell us to do in the alignment instructions so it says to adjust the filament voltage of the AC signal rectifier proceed as follows set the function switch selector switch on the multimeter to AEC so want to set this switch to EC like so so then it says connect the a nur I'm 105 so that's another voltmeter across the inner shield of the AC probe gray wire so that would be this wire right here this is the inner shield we'll take a look at that in just a moment and the chassis ground so we need to basically connect an AC meter to chassis ground and to this portion of the shielding right here so this is the inner shield this is the outer shield so this is ground this is where they're feeding the filament voltage and this is where the signal is coming into the multimeter all right it says adjust v1 filiming control R 50 which is this V R right here until the voltmeter indicates five volts ac so the filament voltage needs to be 5 volts ac so this is the adjustment here see that right there v1 filament right there are 50 so I can get that into focus a little better so this is loose as well so I'm ready to adjust that I'll move this up here like this so you can see how I connect this so what I'll do is I'll take the common are negative see if it'll clip on this if it doesn't I can just clip it on the chassis okay and it'll click this two-year the gray wire and it's not far off five point one volts so I'll grab my screwdriver here and I'll move this around so that's going up so I'll turn this the other way until it gets close to 5 volts now keep in mind that we have a filament in this tube you're trying to do some regulation as well so you can move it and wait a few moments for it to kind of catch up and that is going to be close enough the next thing to do to the multimeter is the AC volts alignment it says here to align the AC function of the multimeter proceed as follows set the function switch selector switch on the multimeter to AC it is on a see from the last adjustment set the range switch to 1 volt it's now on 1 volt connect the ground clip to the tip of the AC probe now I found a screw that perfectly threads right into the tip here what I'm going to do is cut the head of this screw off and I'm going to file that down what I'm gonna do is put these heat shrink tubing on here and I have the perfect probe tip that worked out really nice so that threads into there really nice so the instructions say ground the tip and that's what we're going to do adjust the AC zero control until the meter m1 indicates zero again the camera is looking at this on an angle so I'm going to adjust this to where it looks like it's perfectly on zero so I'm looking at this straight on here disconnect the ground clip from the tip of the AC probe and connect it to the common connector of the meter tester the meter tester is nothing more than a variable AC supply that will supply the voltages for the different ranges for alignment that's all it is so I'm going to use a function generator for the two lower scales here and those are the ones that I'm going to demonstrate really all I'm doing is I'm just repeating myself just upping the voltage and adjusting different you know resistors on the back side so that you know the procedure is pretty much the same through all the ranges one difference is with the two lower AC voltage ranges they are in red on the screen here everything else is using the other scale so one thing to keep in mind that can be very easily overlooked and another thing that's very important to keep in mind is they say align each AC voltage range in sequence so they don't want you to jump around doing this they want it to go from lowest to highest so that's very important so the first VR that needs to be adjusted variable resistors are 35 they mark this on the back says 1 volts 3 volts says all that right on the backside so our 35 is for the 1 volt scale and our 39 is for the 3 volt scale so we'll just take a quick look at that before I start with the alignment here so you can look on the backside just above the line cord here there's the 1 volt and this is the 3 volt alignment so this is the one that I'll be aligning first right there so I'll just have this straight up and down like so that way it's not on such an angle I can get the little adjustment back there all right and so just make sure everything is 0 it again because I moved the meter around it is I'm going to feed a 1 volt AC signal from my function generator at 60 cycles right into the probe tip here and I'll see how accurate this is and that's not too far off it's actually pretty close so let's see I can adjust this up just a little bit and that's right at 1 volt right there and that's it it's aligned so now on to the 3 volt scale I'll get the function generator all set up to do this scale and I'll be right back look at that it's right on the 1 on this one as well I'm thinking that this is going to be probably aligned very well it's right in line with the one there I have the function generator set to 3 volts so what I want to do is rezero the meter here just make sure everything is perfectly zero that was just a little bit high there and what I'll do is I'll attach the function generator to the probe and it's not too far off it's off by one bar there so what I'll do is I'll just tip this forward and put this into the little VR that I need to align there yeah I'll just move that up to 3 volts there it is it's perfectly on 3 volts so it looks like it's off on the camera again but looking at it straight on it's right on the line there so that's aligned the last alignment procedure for this meter is the low voltage supply adjustment it says here to adjust the output of the low voltage supply proceed as follows set the function switch selector switch on the multimeter to ohms it's now in the ohms position set the range switched rx 1 that's done observing the polarity connect the ANU RM 105 which is just another voltmeter across R 47 that's our 47 you can clearly see right there so my voltmeter is just attached across that adjust our x1 our 49 until we get negative 0.9 volts DC so what I'll do is I'll show you where our X is our X is right here on the back so what I want to do is just adjust this until the meter says 0.9 volts you can see we're already at point 9 right there so if I bring that like that right there and at that point it's pretty much aligned to not imagine it it's gonna move just a little bit but that's absolutely fine the last steps of the alignment procedure are a lot of verification so this has to be done once the alignment is done you just can't set it to full scale and then forget about it and think that it's aligned because as you saw earlier when we checked it on one scale it read fine and on the other scale that was way over the three so we had to go in there and address that now this verification has to be done with every scale so every scale every setting every function has to be double-checked and it has to be checked at multiple points on the meter so say we are going to check the 1 volt range we would want to check it out 1 volts and maybe at point 6 maybe a point 2 and just make sure that the needle is tracking correctly with the analog scale remember we're taking a Bolton were turning it into an analog reading here and then we would do with the next the same thing with the next scale and then of course we're going to check all of these we check them all in AC we would check them positive and negative so we would check the negative DC voltage and positive DC voltage to make sure that they track on every scale so as you can see that is very time consuming and then we would check the ohms make sure that the ohms scale is tracking now the unit is off right now and you can see what I mean this is sitting flat you can see how this isn't sitting or resting on 0 anymore oh it's above the zero and again that's because that counterbalance on this end of the needle here isn't being affected by gravity the way it should when you tip this up that phone lines perfectly on to the zero so again that's something to keep in mind when you're using one of these meters they need to be sitting in the proper position you just can't have them sitting like this so lots of verification steps need to be done and that's all part of an alignment procedure so now this has been done with the unit open and in its normal position in every scale checks out perfectly there's no problems with this thing whatsoever but now what I'm going to do is I'm gonna put this thing back in its case and off camera all realign this whole unit all over again to get the maximum amount of accuracy out of this thing when it's up to operating temperature in its case so you can get an idea of how long it takes to do an alignment like this you get an idea of the length of this video just think there's little pieces that I'm just including in here there's all the rest of the time that it takes to do this alignment on top of the the time it took to do this video and this kind of time is relevant for receivers in transmitters and test equipment and whatever you're doing an alignment on most of the time alignments are extremely time consuming and a lot of it is just verification in the end because you'll verify every scale on the device and you'll come to the final scale and then it won't match up and if it doesn't match up you got a search for the problem do the alignment over and start the verification process over again to make sure everything works and again this is for receivers and transmitters and test equipment and all sorts of things whenever you change one component it can affect a whole lot of things and it's not just that that particular component that you're changing is in one section it's the fact that you've taken the thing out of the case and other things have been moved around chances are if your dissol during things you may move wiring around you make move resistors around you know you never know sometimes if you're working on one part and there's a wire that somebody in the assembly process has put on but they haven't stripped it correctly and it's just hanging on by a thread and you bump it and you don't realize it disconnects unless you do the verification process in the end you never find those problems until this thing would end up going out into the field or whatever and then you know a range wouldn't work because it wasn't you know found because it just wasn't gone through correctly and that's I think a lot of the reason nowadays that you find so many you know faulty components or faulty devices right off of the you know grade out of a store or you know right off the shelf is because they weren't you haven't been gone through I picked up a monitor just for videoing here and I bought it at a reputable source and it smells like burnt resistors really really bad you turn the thing on and it just it smells so I looked inside the monitor everything is fine everything is fine so I know for a fact because I have two of the same monitors the other one is fine there's no smell in it whatsoever so it was a warranty return and it obviously went back to the factory and they fixed the problem that went went haywire in it and of course the smell is in there it's a really really tough smell it just doesn't go away in this thing so again you know wasn't tested correctly put out into the field somebody got it probably burnt up in the field real bad maybe smoked up the room and it went back for a warranty fix and back onto the Shelf again and I ended up getting it now the monitor works fine and there's no problems with a monitor it just it doesn't smell very good having it running you know closed at any rate so there it is the thing works really good and get this back into its key and we are gonna do some tests with this thing in the future we'll use this thing in videos and we'll do alignments and I have sections and things like that it's really beneficial to have an analog meter in in those types of alignments it's much easier to you know see when you're peeking a circuit rather than having digits count up and down on a normal multimeter or DMM or whatever you have right so works really good I'm looking forward to getting this thing back into its case and get that last alignment done and this project is out of the way and on to the next one and now for the answers to the electronic trivia questions from the last video in the last video I asked what is this thing what was it used in and what's the part number so if you want to guess at this I would pause the video now because you're about to get the answer if you're new to this so this is a UHF triode used in radar service in world war ii and the part number of the device is Jan sim - 15 e or C V 933 that's the actual part number of this device now I have some plans for this in the future I have a whole bunch of these things brand new in boxes and I'd like to build a simple Class A audio amplifier with this thing and just see how it works it's a really nice looking tube when it's lit up and these pins here will just plug into a standard crystal socket so that's really nice that they did that now the only downfall of running a tube like this in audio service or something like that is you'd have to have it covered up maybe without you know either a glass or pic plexiglass case because this is the plate here so the high voltage is present on this point right here and it's just exposed right because this is designed to be in a shielded box so you know this would look really nice with maybe a finned plate cap and maybe a finned grid cap on the top so at any rate should make a really neat project for the future here down the road so that's what that is a little UHF triode from way back when so now for the trivia questions that will be answered in the next video these aren't two incredibly hard this time what are these things I'm not showing you the top because that'll give it away and look up the part number that way what are these things I'm not expecting you to guess what the actual part is because there are many of these things out there and they do multiple different functions but what are these things called what were they nicknamed there's a big one what were these things nicknamed and where would you normally find things like this you see they have nice gold pins on them very very high quality devices so there you go this will be answered in the next video and of course there will be more trivia in the next video as well I try and include a little bit of trivia in every video every now and then I get skeptical people asking me how does this Carlson low voltage leakage tester work and you know how can it compare to something that tests a device at 600 volts when this is only putting with a bare minimum across a device a maximum of about 27 volts it'll put across a device how can this see leakage at such a low voltage where this requires a very high voltage to see that leakage well I've explained this many many times on patreon and I've talked about this device up there I'm sharing all the plans and everything for this and people say well you know I you know kinda don't believe that this thing is going to do what it does at the low voltage how come they didn't invent this years ago and how come this thing has never been on the market and things like that and the answer is simple it's just called free thinking that's it it's called an open mind and coming up with neat new ideas that solve problems in a different way that's how things get invented today things that haven't showed up on the market so what I'm gonna do is I'm going to show you how this thing works I'm going to show you the differences between this high voltage device and I'm going to take a device is faulty that this will not detect and this will detect it at an extremely low voltage it's designed to do that it's designed to be a safer alternative than this thing because this thing here is testing things right up to 600 volts I have this thing cranked to the max I'll show you the voltages I'll measure the voltages in everything I'll show you the voltage that this thing is putting across the device and I'll show you the voltage that this is putting across the device and how this will detect a problem that this will not it's that simple this thing finds leakage problems that this thing doesn't find and most other leakage testers will not see that as well unless it works on this idea right here here I have two mica capacitors these are great capacitors they're used in transmitting service a lot you'll see t1 b and t1 a on this device right here so this one here is point zero zero zero four if you can see that I've got the lights out so that the displays show up nice right here point zero zero zero four micro farad in the test voltages of about five thousand but it's working voltage is twenty five hundred volts DC so we're not going to bring this thing anywhere near its maximum voltage we're going to only apply six hundred volts across this device so point zero zero zero for micro farad is four hundred Pico farad okay again this is t1 B so we'll take a look at this here in just a moment this one here is t1 a this one here is you can see that on there point zero zero four so that is way up there that's point O 4 micro farad or four thousand Pico farad okay so quite a bit more capacitance in this device than there is in this one here so a lot less capacitance these two capacitors here are just for comparison so this one here is a four hundred and seventy Pico farad cap I don't know if you can see that and this one here's a five hundred Pico farad so five zero and then two zeros 500 Pico farad and we'll test these as well okay so first of all what I'm going to do is I'm going to take my own meter okay and this will measure up to 500 mega ohms okay so I get a lot of people asking you know can you can you see resistance of a leaky cap with this well let's find out tests open 500 Meg's okay this one here tests open 500 Meg's all right so these two here has a comparison again okay tests open tests open okay now let's look at this with a capacitor tester all right so this one here is the point zero zero zero four or 400 Pico farad capacitor okay so let's test this for capacitance I think I need some more coffee so there we go almost 400 Pico farad in fact that screw is getting a bit loose there I'll just tighten this up so 400 right there right 400 Pico farad 396 close enough okay get that one out of the way this t1b okay this is t 1a so this one here should be point zero zero zero four and Oh point zero zero four this one was four thousand so I've to go up to the next scale and there it is alright for nano our point zero zero four micro farad okay so this one here is 400 so let's measure something that's really close let's go to this one right here this is 470 okay so I'll put this one on here oops right go 470 okay 476 not bad and this one here is 500 again five zero zero that's really close these old mica capacitors are really good they're usually always very very close so there are they're rare occasion where they do fill like these devices right here okay so this is a leakage tester that tests for leakage at high voltage okay so right now it's actually the probes are on right now and I have them coasting on the bench here which isn't a really safe thing to be doing so click this onto discharge what I'm going to do is I'm going to put on a pair of gloves because I don't want to come across that I'm gonna tell you the truth I have come across this on this device in the past by accident and it is by far a very very well it's it's put it this way it isn't pleasant it isn't pleasant at all so you definitely don't want to come across this if you're not familiar with using high voltage devices like this I strongly suggest that you don't coming across this thing could be lethal depending on the situation that is a nasty shock when you come across this and I can't specify nasty enough okay so here we go alright so here's the two boots this is in the mica position so we're ready to test mica the capacitors are 600 volts here and I'm going to click this on to leakage so I have this here right now I'm not going to touch the metal together I'm just going to use the conductivity of the boots alright to show you how sensitive this device is at 600 volts so it'll do is I'll just pinch this together like so and look at that okay so if I can get them really close to each other I can just pinch them with one hand okay pinch them really tight so you know no metals touching it's just the boots themselves okay if I touch the metal together you'll see a little spark right see that they're glove under it she's actually arcing okay so the 600 volts they're not pleasant to come across not pleasant whatsoever okay so now if we look at this device this is a the low-voltage device here I'll click that on a discharge this here is the low-voltage device okay so I can take my gloves off for this and this thing is on discharge okay so I'll turn this onto here in fact I'll show you I'll leave the gloves on just so the test is exactly the same okay so suppose to show that my hands aren't interfering with anything right okay so the gloves are back on here the test leads from this device and kind of wrapped around everything kind of hard to get this all in this shot so here we go okay let's get this out maybe I'll just unwrap these as well wires I tell you okay here we go so what I'll do is I'll put these two together as well and we'll see what happens okay no problems okay you see that same thing put them crossways pinch them together no problems alright so there's no touching there you can even put them like this if you want to see them like this so there's definitely you can see that there's nothing touching okay okay same thing is this right it sees the leakage of these two rubber boots alright or nylon they could be they might be made out of nylon anyways they're conductive whatever they're made out of their slightly conductive and it's like this with a lot of test clips so I warned people about this don't ever rely on a test clip to protect you from voltage it might have a rubber boot but that does not protect you from the voltage that's here because these things are leaky like leaky like you wouldn't believe and that's just the way that they are so you saw it on this one with 600 volts it's passing it through these you know through these clips you can see this one right here right these Little Boots right here put them together again click it onto leakage and you can see it's passing it with them this way again so that so that they're you know like this pinch them together don't try this at home okay there is exposed high voltage here and I'm the one that's taking the risks not you all right see that so so there you go so now we know that they're both very sensitive okay so what I'm going to do now is I'm going to test t1 a okay so t1 a will test that one here I'll click this off and I'll put this onto these two clips right here and they're from the device okay so there's t1 a right down there I'll get the capacitor tester out of the way cuz it doesn't need to be used anymore and I'll grab these two probes so we're gonna test this for a leakage here this mica capacitor will test for leakage so here we go okay no problems it's fine alright for those of you that are skeptical and say well how many volts is really across this device here let's find out shall we six hundred and twenty volts is across this capacitor right now you can see my meter is causing this thing to close right because it's showing the leakage it's measuring the resistance meter here okay so no problems I'll hit discharge like so all right take my gloves off for a moment cuz I don't need them for the low voltage tester this is on discharge as well okay and get those out of here now let's test it on this device right here okay the low voltage one so just connect this up give me a sec here I'll just leave it on test I don't need to hit the discharge put this right here let it alone and we'll just wait a moment now keep in mind this would go down quite a bit faster if I didn't hit it with high voltage first even though I've discharged it right you know you get the get a storage effect or a self charging effect in this I talked about the self charging effect in capacitors okay so no problems there this tests fine on this device and it tests fine on this device all right no problems with this capacitor now keep in mind that this thing here that was me touching the leads so keep in mind that when I touch test the other device here where is it right here t1b all right we should have a much quicker result because there's a lot less capacitance here okay now what I'll do is I'll just put a jumper across this and will retest this device here in just a little bit and I'll show you what I mean by that storage effect this here will or that self charging effect so this here will indicate that so just short this out for a while just to make sure that it takes off any of that I'll just put this off to the side okay so now let's look at t1 be okay I'll be nice I'll test it on this one first okay so that I don't hit this with high voltage or anything first so this is just it's just been sitting alright so this is t1 B I'll keep in mind there's a lot less capacitance with this one here okay put this one on here alright that won't move it'll stay like that so this is les capacités alright to give you an example of a good see this is 400 Pico farad this is 470 so it's right around the same area to give you an example of a good capacitor a good mica capacitor at that voltage this is how fast it'll go down okay it's measuring me right now okay so again put this on here just to make sure that it's discharged properly so there is no storage I'll grab a jumper clip and I'll just short this out for a moment okay to show you that everything is good okay and that's not moving okay so now what I'll do is I'll remove this from this device here all right so I'm being I'm being nice and fair because this this is no charge on this thing's been sitting for a very long period of time so it shows faulty on the low voltage leakage tester on the low voltage tester it's testing faulty now what I'm going to do this is in the discharge position is I'm going to hook this up to the high voltage one okay like so put that rate there I'm going to put my gloves back on grab the leads to my voltmeter show you this okay leakage will click it on to leakage no problems tests fine on this device well how is that this is feeding this with 600 volts and it's testing fine on this device so you've seen the sensitivity I can pinch the boots together and it closes the eye so it's reading the resistance of the boots but yet it's telling me that this is fine yet the low-voltage device is telling me that this is faulty okay so here we go let's read the voltage across this device 621 volts that's fine okay now what I'll do is I'll hit discharge let that discharge for a few moments okay and what I'll do now take this off here make sure that everything is safely discharged with this capacitor because I don't want to hurt this sensitive device over here okay so here we are same thing wires are being a little bit grouchy you turn that one around same thing right there this is the sense lead very very sensitive okay so there we go faulty not moving okay let's see how many volts this thing is putting across the capacitor to test it out let's take a look at this okay 600 volts was on this one you have the leads reversed here just to keep it positive a three point eight three volts this is testing and finding leakage in this capacitor at 323 volts whereas this one can't find it with 600 how is that possible that's called understanding the failure point of capacitors and creating a device very sensitive so that I don't have to troubleshoot so much and it makes my life a heck of a lot easier I can tell you that so there you go again okay it's not moving whatsoever so I'll take one here with more capacitance again this has been miss charging for a while he rips wires I tell you that'll be the next invention something that eliminates wires well kind of already have for a few things but okay so there we go look at that so now that I had the shorting bar across this for a while you know I'm getting rid of that dielectric absorption effect look at how fast that move down and this is you know point zero zero four micro farad whereas this is 400 Pico so that's 4,000 Pico and this is 400 and look at how quickly that went down whereas this one doesn't do that so there you have it there is more proof that these devices these ones here can go faulty and not show on something like this where it will show on something like this that thing can save your but if you're looking for a problem and you need to find it in the field and you can't find a leakage issue and it finds leakage issues with lots of different things at low voltage pretty neat so now just to show ya so here's a here's another standard you know 470 Pico farad capacitor I'll test it with this one first so that I don't get such a dielectric absorption effect I keep in mind that I'm touching the leads that's why this is moving up I have to be careful that I don't touch the boots together because if I touch the boots it'll see that as well see no problems discharge it shut it right off like an O quickly that one moves down very good Mike a capacitor all right now if I test it on this one here again it's in the discharge position I'm always very careful to take note of that and I've gone through this and checked everything to make sure everything's nice and solid in there because I don't ever want to get buzzed by that thing again so okay so here we go 600 volts across this this one that's actually rated for 500 so moving down to 500 just to be safe it's probably a little bit more so but that's fine these things will be fine there so here we go no problems right no problems whatsoever okay and then of course we saw that on this one so there you have it this thing finds faults with three and a bit volts whereas this one here at six hundred it doesn't even see it you saw the sensitivity sees the resistance of the boots that alone is proof right there that this thing is sensitive you can pinch these boots together without any metal touching thing closes you saw that same thing with this pinch these metal pinch the boots together without any metal touching and you know this thing closes you know I can grab these and you can see that rate-sensitive this one is right that's just touching the boots low voltage leakage tester finds problems that this doesn't if you're interested in my thought process on how I put these things together how I come up and invent things like this I've invented all sorts of different devices for accurate component testing definitely check out patreon all the plans to build this are there instructions for alignment everything printed circuit board layouts can't get any easier than that so there you go some more fun for the skeptics out there and believe me there are a lot of them pure proof I have lots more I can keep going and going and going in the previous videos trivia I also asked about these capacitors so what do you think is inside these things are they leaky are they a mica cap what's inside let's crack one open and find out this one here already has a crack in itself I'll do that they sealed them up pretty nice take that off even so you can wrap this hopefully it will allow us to do that and we can clearly see clearly see the paper there that's inside this that will keep going and going and going keep on wrapping it it actually came apart pretty nice so you can actually see the paper in there so yes as a paper paper and foil so here's a the answer for a lot of you guys that say paper and oil while there are people on paper and oil capacitors but this is paper and foil so this is the paper and you can see the foil that's why it's called paper and foil I've had many people say paper and foil don't you mean paper and oil well no I mean paper and foil there it is so are these capacitors leaky so this is on a the paper and poly setting so this is a much less sensitive let's call it that setting than the forecast setting okay so this is designed for mica capacitors here so I have a good one here and I haven't cracked open yet okay good as in meaning the case is nice on it so let's put this here well that right there like so turn this on and I would say that that is incredibly likud I should have just gone zip and been over with so just to give you an example here I'll open this up we'll open the sense lead up okay attach this again now keep in mind it's seeing me if I pinch the boots it'll see me right okay so let's do this again you know definitely bad so that's 5,000 pico farads so let me see if I have a good 5,000 or something around how about how about a nice 5600 Pico forget right so here's a nice 5,600 picofarad okay so this is how they should look all right I'll give you an example here I'll just shut this off so it's more of a surprise I'll attach this like so okay so this would be a good capacitor here here we go that's how fast it should go down okay so discharge again so that's a good cap so it gives you an idea of how bad these caps are so if you have find any of these caps in anything they gotta go they're not mica they are paper and foil type capacitor very very bad discharge and test it again as you can see they're horrible so yeah they leak as you can see it's all discoloring and everything is it's getting old so definitely bad stuff there's the paper right there so if you find any of these things than anything definitely get rid of them don't take the chance and leave them behind because if you've fixed something for somebody else and these things are in there it's gonna come back or if you're fixing something for yourself it'll just end up failing got a goal here's another neat device that I've invented and released on patreon for everybody to enjoy this is the Carlson non-contact signal injection probe what does this thing do it'll allow you to inject a signal into components in circuitry without any connection so if you're doing audio tracing this will inject a tone into circuitry as you're going along so you can find where the signals going missing very very useful tool and it's very effective to give you an example of how potent this little probe is there's no amplification in line with this speaker it's just these components here this is an 8 ohm speaker watch this now keep in mind the microphone is quite a ways away from this thing I bring this up here a little closer to the mic [Music] so you can see how potent that is here's another example sure this LED is not gonna like me so I'll put this down here on the desk so it gives you a better idea of the spacing it's getting pretty bright and right about there that LED is getting pretty angry with me so there you go now this is the modulated if I turn this to unmodulated so I can advance the gain rate up to where it turns red this little LED will turn red that tells me to turn it down so I need to turn it down right about there should be good so you can see up here that's that LED is getting angry with me I can tell you that it doesn't like me so that's how much this transfers into a nearby circuit so all the plans to build this thing circuit board layouts everything alignment instructions it's all up on patron if you want to put one of these things together and if you're into audio troubleshooting RF troubleshooting I have troubleshooting this thing is an incredible tool to have it's a really really nice addition to the bench in fact I've used this a lot lately a lot of fun to use as well thanks for stopping by the lab today if you enjoyed this video involving the vacuum tube voltmeter you can let me know by giving me a big thumbs up then hang around there'll be many more videos like this coming in the near future we'll be taking a look at all sorts of different types of electronic devices vacuum tube and solid-state alike so there'll be a lot of repairs troubleshooting procedures restorations alignment procedures and even some circuitry design on this channel so if you haven't subscribed now it'll be a good time to do that as well if you want to be notified right when I upload a video be sure to tap the bell symbol if you're interested in taking your electronics knowledge to the next level and learning electronics in a very different and effective way you're going to want to check out my ongoing electronics course on patreon I'm also sharing any of my designs and inventions up there as well you saw a couple of them in this video here when you do join up another tab will appear that will allow you to join the community section this is where people are sharing their projects and ideas with each other and you can upload your own project and share it there as well it's a great community lots of great people there lots of very knowledgeable people there as well so definitely check it out I'll put the link just below the video description and I'll also pin the link right at the top of the comment section click on the link and it'll take you right there alright until next time take care bye for now

Channel: Mr Carlson's Lab

Views: 113,567

Rating: 4.9187088 out of 5

Keywords: learn electronics, repair electronics, fix electronics, understand electronics, vtvm repair, meter repair, tube amplifier, valve amplifier, electronic restoration, electric restoration

Id: aWgdyoJsVnI

Length: 118min 34sec (7114 seconds)

Published: Tue Jun 18 2019