Voltage drop issues

treborlicec

Well-known member

Donor 2016
Joined
Nov 4, 2005
Messages
6,167
Reaction score
182
Location
Indiana
Just wanted to think out loud here, if I may. On my Circus Charlie, there were these 4 red dots that appeared and vanished all by themselves. I've verified it's not ram related, so I thought "hey, check the voltage". Before any adjustment, I used Mecha's guide and found 4.9 on the roms on the sound board, then 4.8 on the roms of the video (lower) board. About 5.05 at the edge connector. I cleaned the edge connector fingers with a good old eraser. No change. Upped the voltage to where I'm getting 5.25 at the PS, 5.1 at the sound board roms and 5.0 at the video board roms and 3 of the 4 dots went away. Tonight, I'm thinking I will use some sand paper to get some of the oxidation off of the harness connector pins and also tweak them a bit so they make better contact with the board's edge connector. Also thinking I'll reflow the red/black connector that helps 5v get from the top board to the bottom board. After that, I guess a full repin would be in order if no help. The biggest drop is from the PS to the edge connector, so I'm hoping that will eliminate the majority of it. Thoughts? Am I on the right track?
 
Did the sand paper on the connector fingers and adjusted. There's still a good drop but I got that last red dot to go away and the ps isn't over 5.2 so im not in the danger zone.

I decided to check my Scramble and the edge connector was 5.0 even. The switcher read 5.46!!!! Chips on the bottom board read 4.6. That's a big drop. Cleaning the same way as above didn't change anything.
 
Back
Top Bottom