Help with Speedball - One LED does not light up fully [resolved]

musiclistener · 1267

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Offline musiclistener

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Hello,

I'm working on adding the speedball to the crack.  On the first test after attaching the chip, one of the four LED in position D2 does not light up fully like the rest.  The voltage reading I got was the following.

OA 69 V
IA 184 V
B-A/B .1 mV
IB 184 V
OB 71.1 V

Does anyone know what could be wrong?

Thanks!
« Last Edit: July 10, 2018, 06:45:12 PM by Caucasian Blackplate »



Offline Paul Birkeland

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Reply #1 on: July 09, 2018, 12:35:19 PM
Your voltages are OK, but the photo shows a fair number of solder joints on the 9 pin socket that could use a little extra solder.

On the PC board, one way to know you have a good joint is to see a little solder flow through the board and be visible in the hole from the top side.

Paul "PB" Birkeland

Bottlehead Grunt & The Repro Man


Offline musiclistener

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Reply #2 on: July 09, 2018, 01:00:52 PM
Thanks for the advice.  I'll redo my solder joints with that knowledge in hand.



Offline Paul Birkeland

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Reply #3 on: July 09, 2018, 02:20:02 PM
I forgot to mention that the LEDs we have aren't really intended to be uniformly bright.  Having one that's a little dimmer than the others isn't the end of the world, and I've run into that a few times in the past with no associated issues.

Paul "PB" Birkeland

Bottlehead Grunt & The Repro Man


Offline musiclistener

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Reply #4 on: July 10, 2018, 04:00:49 PM
Thank you for the insight.  My build working fine.  Thanks again.