Vintage Tektronix Oscilloscope Restoration

[Music] foreign [Music] and welcome back to ewan's buzz in today's video we're going to be restoring this tectronics oscilloscope from the late 50s to early 60s so let's get right to it so this is a tectronics 502 dual beam oscilloscope so dual Bean basically means it has two channels now this oscilloscope still works very well actually considering how old it is now these telescopes were manufactured from 58 to I think 61. don't quote me on that but I'm pretty sure that was sort of the date when they were manufactured but there is a tech Wiki article that you can take a look which will tell you everything about this I'll leave a link to that in the description now this oscilloscope Works 100 but it can use a little bit of TLC so it lived in a woodworking garage for a long time so it is full to the broom with sawdust so we need to clean it out and just take a look at it but it does work so let me plug it in and get it showing to you well and show it to you working okay so I've got the oscilloscope running and you can sort of see the screen is fading in and out um that is because the intensitivity pot is very dirty because you see it's so it doesn't look too bad here but it's um very all over the place so it looks very bright on camera but it's not but you don't want to run an oscilloscope tube very hard reason being is because it's can burn out the phosphor quicker and you don't really want to do that because you shorten the life of the tube and these tubes can be very hard to find so you don't really want to burn out the tube but if you look at it it's working we can do some adjustments here and you can see I've just got like a little frequency generator that I built in one of my previous videos and you can see that this is a sine wave and I can make it wider and I can make it smaller you can do that as well and I can make it bigger but I'm not going to make it too big because then it starts to distort I think it's that's Distortion but I don't quite know but you can see it's definitely working let's take a look at a triangular wave that down there we go and there is a Sawtooth wave or triangle triangular wave and you can see it's fading again because of this intensitivity knob but there's a triangular wave now let's take a look at a square wave so the square waves those what you have to do is you have to change the input and now you can see my probe really does need to be calibrated as those should be flat not like that so let's grab a probe calibrator tool which is in here which is actually this little thing right here that's a probe calibration tool so let's get it out and we're going to calibrate this probe quickly so whenever you're using an oscilloscope you always want to calibrate your probe that was one thing that I forgot to do now that is interesting that is very interesting um oh it's a dodgy connection from the probe to the oscilloscope but now you can see that is how it's meant to look not all wavy like that so that is a proper Square wave right there and the amazing thing is this oscilloscope over 50 years old and it still works 100 needs a bit of TLC of course as you can see it's uh doing silly things but it still works and it shows just how serviceable and durable they made these oscilloscopes because I've got an oscilloscope which is the tektronics 464 storage oscilloscope that thing was built in the seven teeth not about 20 years from when this was built and it is so much smaller and so much more complex it is crazy to work on and very very complicated complicated this is a lot more simpler it's only I think two megahertz which isn't a lot but for basic Electronics guy like me that's pretty much all I need but this is just one beautiful oscilloscope so in this video we're going to be restoring it together so now you see what it's doing we're going to clean all the potentiometers and we're just going to clean out the inside as it is full of sawdust so let me show you the inside of it but before that it's got a massive fan in the back and you can hear it running listen maybe if I take my mic off you can hear it better there you go so yeah it's got a big fan keeping some very cool little things inside of it cool we're gonna open it up let's [Music] so I decided to go handheld just to show you the sheer scale of this piece of equipment now the really cool thing I was telling you about are these little guys vacuum tubes now vacuum tubes are really really cool they're basically the transistors of the olden days as you can see this oscilloscope does have one or two silicon or maybe a germanium or it could be selenium transistors whoops so it does have some solid state components maybe like oh those could be crystals that I definitely think is a solid state um maybe it's a diode or a transistor but I don't quite know so but what I do know is that these are vacuum tubes and they are incredibly cool now the interesting thing about this oscilloscope is it has 48 vacuum tubes inside of it and that is a lot I mean a lot so you can see there's a couple here there's some more over there um there's a whole lot more underneath here you can see them in there then if we come around to the side you can see some more down here well those are capacitors but there's different Visa more vacuum tubes here and I'll come around this way so you can see and just flip the camera around there we go there's a whole lot up here too yeah a lot of vacuum tubes in this oscilloscope and since it was just on I can feel the heat emanating from it and it is still pretty warm and that fan I was telling you about that's it over here it's a little bit stiff actually it's not too bad now that I look at it that's actually not too bad you can see there's a fan here quite a beefy one so that actually pulls air in and blows it out the vents in these panels but also I'm sure you've noticed something very out of place look at all of the sawdust isn't it amazing that it hasn't burst into flames yet I'm just going to put this back in there for now because I'm going to blow it out with the air blower but there is a lot of sawdust you can actually see it everywhere so let's clean that out and get a better look at what's inside the oscilloscope and then I'll give you more of a in-depth look at what everything does and where everything goes so I need to take off some parts before you can clean this thing because this front panel actually comes off and as you can see there's sawdust inside of there as well so there's a lot of sawdust that needs to come out so let's go outside and clean it up and but first I'll take this off by and to take this off it's actually really simple let me do it on camera for you guys undo these nuts over here and that can take some time because they're very long or the the threads are very long not the the nuts themselves but with the great engineering they usually just slide right off they come off like this you see so they come off really nicely and easily and then you do just need to hold on this aluminum plate so it doesn't fall off but then once you get them off and sorry about the terrible camera angles it's because I've gone handheld I'm still getting used to my new camera but we take this off and that is the aluminum face plate that covers the tube you can see more sawdust we'll put that here and here is the actual graph that would be on the oscilloscope screen and here it is and this is just a perspex plate no no glass but then now that that's over there you can actually see the oscilloscope tube and isn't that one beautiful tube I mean really that looks nice and these little Globes yeah these are for the scale illumination there's two of them and they both still work crazy enough so let's take this outside and give it a good clean so after a nice gentle blowout it's looking pretty good that's all the dust that came out of it oh good dust so it should go away I hope but there was a lot of sawdust in there but otherwise the scope's looking great now you can actually see what the labels say on things so it's a bit bright now but once we're back inside you'll see what it's saying on these labels but otherwise looking pretty good looking pretty good okay so one thing I forgot to take off and I forgot to show you guys was this actually has a big filter on the back so let's quickly remove it so this filter is to prevent dust like that getting in I have no idea how that dust even managed to get in but you know how dust is has mysterious ways of getting into everything more saw dust isn't that crazy so this is a very interesting filter it's actually just metal so I don't know where one would get a new filter like this so I'm gonna blow it out with the blower again and we're gonna take a look more of the electronic side but you can see machined aluminum blades on this oscilloscope isn't that some high quality there so one thing I did forget to show you was this this is not meant to look like that this is actually been a bit of a DIY sort of botch and it wasn't done great I don't know who did it but it wasn't done great as um you can see it's been held together with insulation tape which is already coming off as you can see here it's already coming off and I don't know if it was wired correctly via live in neutral on these prongs now this type of connector I asked some of the very clever people on the tectonics Facebook groups and well on the one tectonics Facebook group that I'm in I asked them and they said that this is actually a United States style plug but you just use an extension cord and you plug in the female end of the extension cord in here and then you plug the other end into the wall and then Bob's your uncle at works but that's not really the case because I'm in South Africa and our plugs look Nothing Like Us plugs our plugs look like this so sort of similar to the British plugs but they're very different so and it would also be very hard for me to get a hold of the United States style extension cord like look it would be easy because I could just say hey um or ask my aunt and uncle or the friends I have in you the US ask them say hey could you ship an extension cord out to me but that's so impractical and the only type of us style plugs I have are those weird multi plugs you know that take a whole lot of different ones and I don't want to be using one of those on here so what I'm going to do is I'm actually going to take this old cable off get a nice new cable put soldered on live neutral and sold on the ground because the ground just goes to the chassis to the chassis here and um put a big thing of heat shrink over it it just seems like the the best thing I could think of doing due to my circumstances currently because I thought of putting an IEC connector on there but then I decided you know what no because then I'd have to modify the case and I don't particularly feel like doing that as I don't want to damage it either so that's the back of the scope so let's start cleaning those potentiometers so here we are looking into the more insides of the oscilloscope now here's the potentiometer that I need to clean they are it's a selection of them but it's mainly the ones that sit underneath the screen but now they are specially covered which is very interesting it except the scale illumination one now the scale illumination is actually this very long Rod here I don't know if you can see me pointing at it but let me zoom in a little bit it is this Rod over here which is a I think a fiberglass rod yes they are fiberglass rods and now that goes to the high voltage circuits right at the back of the oscilloscope because those high voltage circuits need to be isolated so that's why there is a fiberglass rod like this long isolating it that's pretty long but the potentiometers we need to get to are actually behind this little cover and this thing weighs a ton so you see there's this cover here two screws are held well there used to be two screws there I don't know what happened to the other one but these screws that hold this little cover on and I actually need to actively hold this otherwise it will fall but there's two screws holding on that cover and then we're just going to clean those potentiometers because I think those are the only ones that really need cleaning reason being is you don't want to clean the very sophisticated ones that are like down here as those are very finicky and they've been tuned so finely that cleaning them with just the regular Electronics cleaner can throw them off balance so usually you'd use isopropyl alcohol to clean them and make sure it's 100 nice proper alcohol because that can also throw them off um all of this information that I've learned has been from the techwiki site and also all the amazing people on the tectonics Facebook group so thank you so much to them now I'm going to remove this and I'm going to clean the potentiometers over there as that is the intensitivity intensity intensity that's how that's what I was looking for so the intensity and um all the other ones so intensity Focus things like that so I'm gonna quickly clean those and then we will put it back together test if it works and hopefully that fixes our problem [Music] [Music] thank you [Music] okay so I've cleaned the potentiometers and I've blown a bit of warm air on them using my soldering station just to make sure all the contact cleaner evaporates as I don't want it to stay in there when we turn it on so as I've got it now I want to just turn it on to make sure everything is okay and to see if anything improved which hopefully it did but now this oscilloscope I feel like it was stored somewhere funny as it's got the weirdest nastiest stuff all over some of the connectors I mean look at that it's pretty gross I don't know what it is but it's just kind of kind of nasty so I think before I turn the oscilloscope on I'm just going to clean out these so I'll do that real quick um that shouldn't take too long then I will just put the this black thingy back on the tube as I did clean the tube as well so we can actually put that back on right now so that is the wrong way as the deflection well as the spots for the lamps or not um you know you can't see the lamps it's actually give the light gloves just a little bit of a clean as well there we go lights all clean and then yeah so there's just this nasty Gunk all over it I don't know where it came from but it doesn't seem to be causing problems but otherwise it's looking fine it's a lot cleaner inside so you can actually see what's going on um let me clean these plugs and we will fire up the frequency generator and fire up the scope and we'll see how it's looking hopefully it's looking better all right so I have made connected everything up still on the Square wave we should still see a square wave ah speaking of which should actually turn the light off remote controlled light pretty neat anywhere so let's turn it on so interestingly enough to turn this on you actually turn on using the scale illumination switch I had no idea it's actually a potentiometer and um yeah it's a potentiometer and a switch so look at how it just Springs to life isn't that beautiful apologies if there's any wind noise as I know that can be kind of annoying but let's wait for it to warm up it's going to take some time as it's a vacuum tube scope but if we just give it a second or two it should warm up it's truly a beautiful piece of kitty so hopefully I've maybe not restored it to its former glory but really gotten it close let's see what happens hey it's warming up it is warming up that's even on the screen real quick let me turn the scale of Illumination off just so you can see the screened here and I'll crank up the intensity and would you look at that it's staying there it's not moving nothing's happening we fixed it we fix it I mean it's such a great feeling when you fix something but it's even better when after things have been going so wrong you finally fix something and it doesn't go wrong it's a really nice feeling it really really is I mean it's staying there let's try change it to a triangle wave we'll see what we get wow just look at that turn down the intensity just a little bit for the camera there we go and now look intensity can be adjusted without it causing problems and it hasn't even changed or faded since said that was pretty successful now let me show you something Ultra beautiful so you guys are going to love this let me turn off the other lights so you can see it even nicer so here's the screen doing what it should be doing and here is where everything will be connected now the face plate needs a very good clean but otherwise it's looking good but here's what's something super beautiful I want to show you it is so beautiful you'll never see this in any modern equipment isn't that so pretty you've got all these little lights glowing and making Heat and look at the difference in them and these all the heaters in the tubes so you can see the heater in this tube is like a disc this one is probably just a little little filament coil and so on the rest of them excuse my shaky hands I'm really excited I mean look at how beautiful that is and there's more you can see even down here the way they glow it's really cool even inside the CRT tube which is this I'm not going to touch it because that's very dangerous and this is why I really really really have to point this out do not go playing around in things that use vacuum tubes if you don't know what you're doing I've been taught on how to be safe around them and I have a basic idea of what I'm doing so as you can see if I can get it closer so this is a bit hard to see as the filaments all in the back but you can definitely see it through there isn't that pretty now let's look at the bottom okay so there's no more tubes at the bottom you can just see the sheer scale of this thing it's so beautiful it really is now let's look at these ones now this is something I'm a bit scared of doing because I'm reaching over the scope and you can see all of these ones just glowing away oh no way look at this there is a neon lamp over there and it's glowing I wonder what that does but man this thing is so beautiful I say what we do is we put it back together and clean it up really nicely over before we do that I must put on the new power cable so let me put it back together and we can put on the new power cord [Music] my story [Music] [Music] [Music] [Music] foreign [Music] okay so the new power cable went on really nicely um the scope's looking good I just need to clean it and put it back together so that's what we'll do now but I've cleaned all the controls that I suspected needed cleaning so they are looking a lot better and not being finicky the knobs are very dirty um I don't know why it's got the same sort of Gunk that the connectors have on them so I'm going to try to see if maybe cleaning it with some isopropyl alcohol will get the gunk off the connectors I'll take off the these like because these come off they're like adapters they come off like this so I'll clean these with ice Purple alcohol but one thing you never do with tectonic Scopes is clean the faces with isopropyl alcohol because that can rub away the text and the numbering so you don't want to do that so yeah otherwise it's looking nice new cables on it's a little bit short the new one but otherwise that should be not a problem so let's clean it and put it back together so something pretty crazy happened while I was working I well while I was cleaning the knobs on the front at least they broke off yeah some of them broke off which is these two so yesterday while I was filming I decided Well I'd probably not be too chuffed with this and I was a bit frustrated so I super glued them and said I'd wait for tomorrow so now it's the next day here are the knobs now we might oh dear you might need to maybe file them down or something maybe use a bit of sandpaper let's try a file quickly see if that helps just to get rid of some of the solid super glue because they're too wide to now fit flush which is an issue which hopefully we can fix if not we can always 3D print these knobs well these uh little like shaft pieces because these little shaft pieces are actually what broke and I did check they didn't break right off the they didn't break right off the potentiometer which is good because I was worried at first that that's what happened but luckily they didn't which I'm very thankful for see if this will fit in now it's not just a tad but tight um let's see because what I'm hoping is that the super glue went and the cracks and sealed it from inside the cracks and not just from completely outside the potentiometer so I'm gonna have to do this to the other knobs to hopefully get them to go inside the chassis otherwise I'm going to have to 3D print some new ones because they've got a special way of coupling to the inside potentiometer so yeah let's see if this works now little just slightly too thick yeah so I'm gonna work on these try get these open and we'll get these a lot thinner hopefully that works and we'll see what happens because these I mean just slide in like that and go on to these potentiometers because first of all what I need to do is I need to slide them in turn the potentiometers down to the zero position and then align these knobs with these ones so hopefully I can get that right my main hope is that that same thing doesn't happen to this one is this knob is a little bit tough to turn and I don't know why but this one should be fine I would also be worried about this one as well but uh that one seems to be okay so we're going to leave it at that but yeah let me get these knobs smooth and we will come back to that so I'm going to get these knobs all smooth and flush in my dad's Workshop because he's got like sanding paper and all that and I don't have that so I'm gonna quickly do that and then once these knobs are back in we'll get straight back to cleaning okay so this video got incredibly delayed incredibly fast and I can explain why so the knob did break like you saw in the last video you saw I struggled a lot well the little shaft I mean and I also got six I was ill for the past three weeks which wasn't fun but that's all fine I'm better now I might still be a bit croaky but otherwise I should be fine so here are the knobs these ones broke off well the shaft broke this is an original Shaft but when I tried super gluing the other one this one didn't fit either so luckily the potentiometer inside has the same geared end inside it so we just modeled a new shaft of this and now I've got some 3D printed new ones so these fit on sort of a little something like this it fit on quite snug too I'm not going to push it all the way in as I might need to take it out but what we're going to do is we're going to fit these on the scope and we're going to fit them on this knob the snot this potentiometer these three because this one doesn't use that but I do need to line up all of the knobs because if I don't then these will not be sitting in the right place and also I don't think these potentiometers all the way to the zero position so I just want to zero them and put these new knobs on so let's do that foreign [Music] [Music] okay so the knobs are back on and aligned now there's one issue though I was taking these thingies off and I heard a cracking noise and I was like oh it's probably just these old shafts but it was not it was the knob and since I think these are Baker light knobs it chipped quite badly on the one side so just put a little bit of super glue there to um stop from cracking anymore but I did damage the window but otherwise it doesn't look too bad it's this one right here you'll probably see it when I clean it but as you can see all the knobs are working fine so we've got scale illumination intensitivity knob and beams Focus so that's pretty much everything that needs to be done to the scope to get it fine so now we can properly clean it and we will start with the front and the back but I'm also thinking of maybe we put it all back together and start cleaning it with the side panels on because otherwise it's all fine it should be all right yeah because I'll just clean it with the front panels and all of that as I just want to re-clean them but I need to put some stuff back together so I'll put it all back together so that no water or anything can get inside so let's get started okay so I've put the panels back on and sorry I bumped the mic that must have been quite loud but I've got the side panels back on and let's take this outside to clean because I'm going to just use dish soap and some warm water as these Scopes you don't want to clean them with anything too aggressive because that rubs away the writing and I find dish soap and water works quite well because I'll use the dish soap and warm water well the first sort of clean then I'll use um just some regular water just so I can um I want to say rinse it off in a way because I don't really like the sense of that that sort of soapy residue sitting on the scope so it'll just be some warm water and then after that I'll take a dry cloth and just wipe it down but it went back together nicely and I'm sure you saw in the time lapse I did actually plug it in just to test it because um it has been three weeks and it's been sitting on my workbench in pieces for quite some time so I didn't want to put it all together clean it up and then all of a sudden up damn it stopped working but no it hasn't it's still working fine and that signal is so clear so what I'll do is I'll use a microfiber cloth to also clean the screen and we're going to get all these knobs and everything nice and cleaned up so let's go outside and do that [Music] thank you [Music] foreign [Music] [Music] foreign [Music] foreign [Music] foreign [Music] I didn't want to let you see it warm it up because it is fine I know that but um these the intense intensity control is a little bit uh wonky so it still works fine it's just you see the one channel cuts out before the other one does one they should be sort of equal but I mean that's all right maybe it just needs a little bit of extra cleaning but it's working and you can see both channels on the screen and I've turned off all the studio lights there's just the one room light and let me show you how so here we've got Channel One and yeah that is pretty bright so I should turn it down usually it should sit at something like this at this sort of brightness because then you don't risk burning in the CRT but otherwise it's doing fine let's um maybe try a sine wave look how much smoother that is so now to just show you the other channel I'm just going to move that one off the screen and I will move this one up now you can see there's a sine wave so we can see how it looks and all the controls are working too and we can let's say increase that and there we go and we can make it bigger too Rock Channel there we go now Isn't that cool so we have successfully stored a tectronic scope from the late 50s to early 60s thank you guys for watching I know it was a long video and thank you for your patience with me as so as life goes but thank you all for watching I really hope you enjoyed it have a good one bye

Channel: Ewan's Buzz

Views: 6,877

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Id: N3FzSw0ul1k

Length: 39min 11sec (2351 seconds)

Published: Sun May 14 2023