#062 FeelTech FY6900 External Reference and PSU Mod

hello and welcome back today i have the the fieldtech fy6900 and i already had a review about this one just how to use it and i still think it's nice there is one thing and because i use now lab reference for everything so i like and there is no external input to put a reference i already found that there is a little oscillator inside here and it is below the cables it is well i will zoom in on that later um it is 10 megahertz so we should be able to to make an input for that also the problems that the former models had with the power supply some people said they had 25 or 50 volts on the connectors they solved it here in this in this model by just putting a earth connection so it's less floating but then they use this little wire that is absolutely not rated to do so so we will put a bigger wire there and i found another interesting video i think it was from a german guy and instead of just replacing the whole power supply on his uh that was the type before i think the 6 6800 he just this y capacitor right there it just took out and he took two other y capacitors and put them to to ground to the earth connection so first i'd like to see how much voltage i have here and then maybe i also do that modification and of course replace this by a proper wire and yeah first we're going to see if the if we can measure on the oscillator which pin is what and then we add the bnc connector in the back and make it switchable to open it there is only one screw in the bottom and you will foil your quantity of course but i don't think you can afford sending it back so it doesn't matter in the end i have this uh special tools and it works great too to to open because there is a one here in the middle it's already open there is one here on the side loose one area and then it's loose so that's how you open the doll thing and you make no scratches now it is completely open uh i could still switch it on and if we look right here we need to be careful here about the right side because this is open here we have the little oscillator and if it wants to zoom in correct oh he is beautiful you could see it's uh 10 megahertz so i just gonna measure some voltages and see and to see which is the output pin so okay i found out where all the pins are the pins are a power power ground and uh and signal so what i'm trying to do i want to i want to inject the signal here on this leg so it is only four legs so maybe i will just try to desolder and then put the oscillator straight up and then i can put the switch in in the pins uh between and i just connect the power with a straight wire because this oscillator i can continue to to run i don't mind too much and yeah then with the switch you just use the external input or the oscillator input so but it's all very small so i need to be very careful not to break a trace or i just need to see how i do that i do have a heat gun but i never did this before so i hope i don't completely ruin the board by doing so and uh oh that is hot so let's try to heat see if it moves the cable is a bit short this is not ideal i think yeah it moved okay it actually went quite well okay the rework station also comes with this tiny point so i try to clean up a little bit the pads what i'm thinking of doing is just put a put the orange light straight up like this and then of course i need to put a little wire from this this pet to here and here to here and this one is going to be switchable and i think then we have the shortest connections oh it does look i was able to put the oscillator back in its place with the two legs up does not look necessarily very sweet but i think it will work i just need to see if it if it is short circuiting on the housing but i don't think so because that tilted little bit forward and then the housing is touching the plastic so but i will measure between the housing and in the legs and now we're going to connect the ground pin and i will just put that on the on the pad where it was yeah it's all very small here is the ground pad and i'm and then i'm gonna connect it to the thing right there i need the microscope i think and let's see if we can do that so i put a little yep right there on the bottom not too much okay uh besides that the ground pin is now connected it also creates support so it doesn't fall so it's really stuck and it seems to be soldered well so let's see if we can put the signal pin it's going to be very tricky now because there is not too much support the thing is this the the oscillator is just flying and yeah so what i'm going to do i'm going to put here uh i'm going to put here a bnc a png and a switch and then we can switch from the external here or we just make a connection between these two so then it's internal or from the internet we have the two holes and yeah we can put another switch in the b and c through it here it is bnc connector in the switch and then we can just switch from internal to external okay here it is i will put 50 ohms just to to get to the impedance and i will put one in as a dc blocker let's see if that works with the dc coupling and the 50 ohms so i'm going to put that in and then i should have on the middle pin let's put this look around then on the middle pin because we did switch to the external i should have then huh yes 10 megas exactly so it seems to work fine look i put there the signal just goes through the cap and then to the switch well that seems all very nice and also from the inside we have enough space to go everywhere okay well i would have liked to use this coax cable to connect it but it is not that flexible and also i i i notice i will put too much strain on the contacts on the pcb but and i remember seeing in my my hp counter that i also used just little wires because well 10 megahertz it's it's almost lf if you would say so if it's short enough it will probably not be a problem here we have the here we have the switch as you can see the switch switch is between just connecting the oscillator or when it switches to the middle pin it just goes here through the seat and then to the board so that's how we switch and it actually does look very nice so uh let's see if it still works if i didn't make short circuits okay i put it back together again so uh i need to see if if it still works i switched it to internal because of course we want to first check internal if it still works if it still starts it does start so i think it's also the processor that runs on the same clock so but uh let's see if we put signal channel one should be i don't know if it's it does 10k very low power yes so that still seems to work let's see 10 megahertz okay well that looks nice now let's see if we switch because it doesn't say 10 exactly i will show you later so now we're going to switch on to the external and i think i will switch it off just to be sure that it doesn't go all crazy if the processor also runs on the same clock okay here we go it does start or not no there is no output okay it does work again um i just needed to power it off but i also noticed i forgot the ground wire because of course i can put the 50 ohms but it's completely floating so i also connected the ground to the ground of the other bnc right here so but i have now a signal of 10k i'll switch it off completely then go to the external reference switch the switch over power it on and we have a signal we have a signal so and it is 10.00 that is what i wanted so it seems it seems it's working that is great so let's put 10 megahertz this one down and now we should have 10. yeah this is exactly 10 look at this this is on the external reference let's see if i can just switch over or it will just just totally crash no it will crash okay i really need to power it down i'm going to do that the processor also runs on the same clock so i hope i didn't damage the memory let me go back to then oh my gosh again here it is now you see this is his internal clock which is not exactly 10 that's the whole thing why i wanted to do this and now our switch open power of the device power it back on and here we are on its own on the external reference this is cool this is what i wanted there was one other issue and i saw a lot of that on on other videos especially on the formal models of this one that didn't have an earth connection it just had the two wire from the mains and this one does have three because it has earth or ground and the issue was if you put it on ac you just hold one and the other one you put in one of the bncs and then you see now we have two volts ac that is uh not bad but you prefer to have it a lot lower and but the other models had above 20 sometimes even 40 that was dangerous i still like to change the ground wire and i think i also make the other modification so what i did instead of putting that little tiny wire that should be ground i just put it directly on the board and then instead of the y cap going from the primary to the secondary side i just put them i put another one in the original is on the secondary and i put a new one here you can see it's now two i will put the schematic lighter and they are about to ground and the good thing is doing that because i should have not necessarily do the primary side the hot one i i don't need to do that but it's also nice because if you somehow lose your ground then it just steps over and you can see in the movie i will put a link well let's see if it works and it at least improved well the the the earth wiring looks a lot better i would say so now we have proper earth connection let's see if it doesn't blow any fuses and if it starts yes it starts is it still working yes it says 10k but let me see 0 1 10 megahertz well it's the more or less 10 because it's running on internal and do we still have ah it's not fair and hook it how much voltage we have we have 360 millivolts i would say this is a success so from two volts we could even cut it better and now it's 330 millivolts i would say success so here we have it our modification it's all back together again looks nice and sweet like nothing happened only an extra switch and a b and c in the back so this is how you can put an external reference to your signal generator so it's more precise because this one actually goes up to 60 megahertz so you can use it for 4cb if you want but and it does a fm modulation so but then you needed to be precise so external reference that's it thank you for watching and i hope to see you next time

Channel: Tony Albus

Views: 6,744

Rating: 4.9194632 out of 5

Keywords: pe1ons, feeltech, feelelec, FY6900, 10Mhz, PSU fix

Id: X_fbDlpxg_M

Length: 22min 48sec (1368 seconds)

Published: Sat Aug 15 2020