Speedball C4S Board LED's not lit [resolved]

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Offline [email protected]

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on: August 09, 2024, 10:38:57 AM
I built a Crack last year and gave it to my son. At the same time, I bought the Speedball kit and decided today to build it and install. I'm pretty meticulous, and I've reviewed the instructions and my build three times, but I suspect I'm missing something and need advice if someone is willing.

The Crack was working correctly since Christmas with no mod's from stock. None of the four LED's are lit. The LED's on the 12AU7 are lit and the tube glows.

Voltage readings:

OA = 67.6VDC
1A = 179.1
B A/B = 0
1B = 178.7
OB = 64.7

I don't see cold or missed solders. I haven't plugged in headphones until my work is reviewed.

Here's some pictures. Any help, guidance or advice is gratefully appreciated. I would like to know if it's okay to take it for a test run, or if there is a problem to troubleshoot.
« Last Edit: August 11, 2024, 05:57:20 AM by Paul Birkeland »



Offline Mucker

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Reply #1 on: August 09, 2024, 11:52:31 AM
I believe they are lit but it's common to appear dim with bright room lighting. Did you turn off the room lights because your voltage numbers look fine?



Offline [email protected]

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Reply #2 on: August 09, 2024, 11:56:03 AM
Ah! I did not! I will check that straight away. Thanks kindly for your reply, it is very much appreciated



Offline [email protected]

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Reply #3 on: August 09, 2024, 01:37:54 PM
Indeed the LED's were on, just very dim. Completed my tests, powered it up, and... wow! What a difference. Glad I did the upgrade!