tron linear power supply fed by what? Big Blues?

andrewuts1

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Can someone tell me do the two big blue capacitors on the floor of a tron feed the J4 molex connector on the tron linear power supply. I have a known working linear power supply and pcb. When powered on I get far less than 5.1v at the +5v measured at my pcb. I was thinking maybe one of the big blues are the culprit. Thanks, Andy
 
The 100000uf cap filters what becomes the 5VDC line.

The 55000uf cap filters voltage that becomes part of the 5VDC line and the 12VDC line.

The 3.5uf oil cap also ends up at the 5VDC line.

You could also have connector issues.....depends on how low.....is low.

Edward
 
He's tried hooking the PCB up in another cab (it works fine).
He's tried hooking up a known working power supply (won't boot - no raster)
He hooks J4 to a switcher, the other connectors go to the linear PS and
it works...sorta...when it boots it gets stuck at the grid screen. Testing +5 at the PCB (off one of the eproms) gives his +5 (or just a tick above)...

Pressing the reset (the one closest to the front of the cab, not the one near the yellow LED) it "sometimes" runs thru the POST test and starts...other times it stays on the grid and there are flickering "specks" scrolling diagonally...

So (with all that eliminated) I can't help but think it's one of the blue filter caps...especially (as confirmed in above posts) they deal with the +5.

Whoever had this cab felt the original linear PS wasn't doing it's full job, so they hacked in a switcher for the +5.
 
tron linear power supply

Thanks for everybody's help so far. I've got an extra set of the 55000uf and 100000uf caps handy so I think I'll swap them out and try it again. Thought I'd ask some experts before going any further. Andy
 
tron

Swaped out 55000uf and 100000uf caps with no luck. When I run it through the linear power supply I get no picture, no sounds, nothing. Can someone tell me if the power supply conversion kit arcadeshop sells will circumvent all of this stuff on the floor of the cab? It looks as if it will with the exception of the 3 prong molex connector which goes to fuses. If it does I'm purchasing one. Thanks, Andy
 
Yes, the arcadeshop bypasses those caps and the transformer. I had a similar problem to what you are having and the arcadeshop conversion got it back up and running.
 
Swaped out 55000uf and 100000uf caps with no luck. When I run it through the linear power supply I get no picture, no sounds, nothing. Can someone tell me if the power supply conversion kit arcadeshop sells will circumvent all of this stuff on the floor of the cab? It looks as if it will with the exception of the 3 prong molex connector which goes to fuses. If it does I'm purchasing one. Thanks, Andy

Let's backtrack a little.........what are the voltages?....at the power supply and at the motherboard.

Edward
 
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