Passed Resistance check, No LED lights, no voltage reading [resolved]

[Ricochet3004]

Hi guys, sorry for some dummies' question.

I have recently assembled a bottlehead Crack and passed all resistance check according to the manual. However, when I move on checking voltage, all the readings on the rail from 1-10 are all 0V. all LED lights does not light up as well (the voltage between them are ~0.5V each). Thank you for your help !!

[Paul Birkeland]

I'll just post all that I observe, but note that it's not in any particular order.


The green twisted pair wiring is not routed properly on the 9 pin socket. 

The black wire going to the center lug of the 9 pin socket appears to be stranded.  What happened there?

 The 4-40 screws are a bit mixed up between the two sockets.

 A4 may not be soldered.

Your power transformer is installed backwards and your power supply appears to be built kind of upside down.  When you went through the instructions and discovered that the transformer was mounted backwards, it would have been appropriate to stop and fix that.  I do also notice that you have avoided posting photos of the entire power supply which would make this issue more apparent.

Your headphone jack is miswired.


I would strongly recommend a complete rebuild at a far slower and more careful pace.

[Ricochet3004]

Hi Paul,

Thank you for your advices, rebuilt yesterday and I spotted that I miswired one wire from terminal 14L (which supposed to be terminal 13) to the 8-pin octal slot.

The amp is working beautifully now!!