No voltage on OB, A3 LED not lit [resolved]

[popthropologist]

It was going smoothly until it wasn't. I have been enjoying the Crack and decided it was time to add the Speedball. I populated the small board, soldered, and when I went to check voltages I got:

a bit of smoke coming from the resistor at 14/15.

I quickly unplugged the amp, noticed a loose connection at either 2U or 3U that I reflowed, and then I plugged in again--no smoke, and my readings were:

OA=81
IA=193
B-A/B=0
IB=193
OB=0

I also noticed that all LEDs light up except the LED on A3. However, both sides of the 12AU7 light up.

I tried reheating the MJE-350 on the OB side, reheated my connections with the white wire on OB going to T5 at both ends, even removed the MJE-350 and the solder from the holes, then installed and soldered again... I'm still getting 0 at OB and the A3 LED isn't lighting.



Couldn't find an answer from previous postings on the forum, so here I am... is anyone able to diagnose the problem for me?

Thanks!
Jon

 

[Deke609]

Hi Jon - Some of those connections on the underside of the board look like they could use some more solder. One looks not to be soldered at all - see circled connection in the attached. 

Hope you get it working soon,

Derek

 

[popthropologist]

*face palm*

That was it, exactly. Working and testing correctly now.

Thanks a mil!