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46  Tech and Marketplace / I need help with my game! - Technical Discussion / Re: Williams power supply. Not enough 5+ voltage to the CPU/ram board. on: February 01, 2015, 03:48:22 pm
I don't have an ESR Meter, I noticed my header pins are a bit rusty and I'm wondering if that's producing some resistance so maybe I'll take a flex stone file to those pins and maybe clean up the rust a bit.
47  Tech and Marketplace / I need help with my game! - Technical Discussion / Re: Williams power supply. Not enough 5+ voltage to the CPU/ram board. on: January 31, 2015, 12:17:22 pm
Pictures:

Bridge Rectifier looks a bit haggard


Previous owner removed the damn header coming from the AC & transformer for some reason but I'm fairly sure its not the problem. I reflowed the solder anyway.


48  Tech and Marketplace / I need help with my game! - Technical Discussion / Williams power supply. Not enough 5+ voltage to the CPU/ram board. on: January 31, 2015, 11:48:02 am
[Robotron] Originally the PS was dead. I used the Bob Roberts rebuild kit and brought it back to life, kind of...

I'm getting ~4.7 volts or less to the cpu board at times. It fluctuates so I can get 4.9 sometimes and the games works, but that's not good enough.  I replaced the harness, reflowed solder and reseated connections, etc. I replaced the ICs and caps but not the bridge rectifier as it wasn't in the kit.

Is it worth trying to fix? Are Williams power supplies too finicky? The problem is I can't adjust the voltages, The original Williams doesn't have a voltage adjustment pot. I heard there's a guy that installs them.

Or should I just get a switching conversion kit? The arcade is 100% original with the exception of a repro CPO so I would like to keep the linear in there, what do you guys think?
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