My first Sanyo ez cap kit - went from jailbars to vert collapse

Bullwinkle

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My first Sanyo ez cap kit - went from jailbars to vert collapse

Is it likely that a cap kit could cause a transistor to fail and result in vertical collapse? Started with a pic that had jailbars and too much green... Capped it and now have vertical collapse. B+ is at 108.23 vdc. I've double checked the caps for shorts and polarity.

Bout to order some transistors for 402 & 403 but wanted to know if I should look at any other components in case I have to order other stuff too.



Thanks
 
don't order parts just because. test them to see if they are bad first.

it could but usually it is something that happened during the cap kit.

it may be a cracked trace.
cold solder joint.
broken pot on the remote PCB check the V-Hold one very closely.

re-flow all the header pins and all the yoke pins. all the big resisters. and all the bigger transistors on the heat sinks. also re-flow the entire neck board as well.

Peace
Buffett
 
Remember you can usually check transistors to some degree with a multimeter. Check for continuity/closed circuit as you would for each pair of diodes in the transistor, it's not a perfect test but it gives you a good idea.
 
Remember you can usually check transistors to some degree with a multimeter. Check for continuity/closed circuit as you would for each pair of diodes in the transistor, it's not a perfect test but it gives you a good idea.

I did do this, and had no continuity between any of the pins. I will reflow solder on all the parts previously mentioned above, hopefully it's something simple like that.

Thanks
 
OK, finally got this back to my test bench (and finally got my test bench to be able to do Sanyos) .. Was able to correct the vertical collapse, now on to the last component.. No Green! I have run the rejuv on it to test and it shows the green gun in the low Yellow area, so I did do the rejuv for that gun and it corrected it (all guns now fire perfectly)

But still no green. Going to go back down and play with adjustments one more time and then start troubleshooting the green circuit.

but hey.. some progress anyway :)
 
One of the legs of c408 was soldered fine, but apparently the trace lifted underneath it and wasn't making good connection beyond the leg of that cap... so the E leg of TR402 wasn't making the complete circuit.

On yet another note, apparently (and this is a guess, but it seems logical) my inverter board isn't inverting the green signal properly. If I plug the game in without the inverter, I get the lovely image that looks like a photo negative, BUT, I can adjust the green bias pot on the neckboard and the color on the screen changes (not to mention I see green)... then when I hook it back up properly, the neckboard green bias and the inverter board's green controls don't work at all..no change in anything.

Where I don't have a nintendo cab to test the monitor, is it a decent assumption that the monitor is actually fine and my inverter is the issue?

Thanks
 
OK, what's the best method for testing transistors, I'm not sure I'm doing it properly. I'm using my DMM in diode mode to test. Is there a different way and what should I be looking for, shorts?
 
that's the best way to do it unless you have a separate transistor checker.

most times its red lead on the base and the black on the collector and then the emitter.

then reverse the leads and test again.

compare both readings to the other transistors in the other color circuits they should be almost the same readings.

Peace
Buffett
 
that's the best way to do it unless you have a separate transistor checker.

most times its red lead on the base and the black on the collector and then the emitter.

then reverse the leads and test again.

compare both readings to the other transistors in the other color circuits they should be almost the same readings.

Peace
Buffett

OK cool..that's what I've been doing is comparing... wasn't sure if there was something I wasn't doing correctly. Thanks.
 
Well.. I can't say that the transistors showed different values.. but one was definitely bad. Moved both green transistors into where the red transistors were and red to green..and low n behold, now I have green and blue with no red!

This make me oh so happy :D

Thanks for the help..now just have to order a couple transistors and I'll be good to go!
 
Well.. I can't say that the transistors showed different values.. but one was definitely bad. Moved both green transistors into where the red transistors were and red to green..and low n behold, now I have green and blue with no red!

This make me oh so happy :D

Thanks for the help..now just have to order a couple transistors and I'll be good to go!

This is actually BAD NEWS! You will need to find a donor chassis, as the color transistors for Sanyos are not available according to what Bob Roberts told me.
 
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