Speedball 1st Board Voltage Issue 0B (Solved)

Jake1 · 548

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Offline Jake1

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on: June 25, 2018, 01:11:12 PM
Hello,
My crack had the correct voltages and I just finished the first PC board of the speedball upgrade.  All the voltages except for the 0B part work fine.  The 0B keeps reading 0 though and I'm not sure how to fix it.  I'm pretty sure there aren't any mistakes connection wise as I had this voltage working before and haven't changed anything except redoing a few soldering points.  I assume 5U is important and have cleaned that up the most but haven't had any luck getting it to work again.  Are there other parts of the path related to 0B that I could work on?

One thing that might be an issue is that I wasn't sure which of the 0A 1A etc. Points to thread the wire through.  There's two holes for each that looked connected so I assumed it was arbitrary though.     
Voltages:

0A: 90
1A: 180
B-A/B: 0
1B: 180
0B: 0

Any help would be appreciated, thanks!

Solved: The problem turned out to be a poor connection with one of the prongs of the 2907A transistor in Q1B if anyone has a similar problem!

« Last Edit: June 25, 2018, 05:18:04 PM by Jake1 »