Speedball: LEDs on first board not lighting; voltage tests are within spec

agitprop

New member
Built Crack yesterday.  Tested and worked well.

Just installed first half of Speedball.  None of the four LEDs on the Speedball's small board light up; the two original LEDs on the Crack's 9-pin socket work fine.  I'd be shocked if I overheated the four small-board LEDs when soldering; they got a lot less heat than the 9-in socket LEDs. I am using a Hako digital iron at 650 and Cardas Quad Eutectic, and I have a good bit of soldering experience.

Got the following, ostensibly nominal test voltages:

Terminal    Voltages (DC)
OA                      80.8V
IA                    176.2V
B-A/B                      0V
IB                    176.5V
OB                      80.5V

I would love to include photos, but I can't figure out how to either directly include images or share imgur links in a post.  Please feel free to clue me in!
 
When you post, click on "Attachments and other options" and then "Browse" and then add your photo.  Click on "more attachments" to add additional photos.
 

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Thank you!  Photos follow.
 

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Hmmm.  Here is the cover photo of the Speedball manual, which shows the orientation of the transistors matching mine:
 

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Do these LEDs require the amp to be pushing audio to light up to a brightness where they can be seen in normal lighting?
 
Sounds like your amp has the right voltages so you should be good to go. The big board LEDs are about the same brightness as the 12AU7 socket LEDs. The small board LEDS are much dimmer because they pass less current. You may want to darken the room to observe them.
 
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