Speedball - I goofed, but what did I damage?

Bungwu

New member
So I had the Crack assembled and working and began the speedball upgrade

I am new to DIY soldering and circuits and I failed to recognize that the 2N2222A and 2N2907A transistors were different despite the big red warnings in the manual. I thought it was referring to the resistors, not transistors.

Anyways, a quick run down of what I did:

[list type=decimal]
[*]one 2N2222A on the bottom right small PC board
[*]one 2N2907A  on the large PC board
[*]finished assembly, powered on...Tubes lit up, powered off to test voltage
[*]powered on to test voltage, noticed not all LEDs were on... little bit of smoke... powered off
[*]removed PC boards from Crack, checked all solder points(re-did a few)... reassembled, powered on, same  problem as before: tubes lit up, some LEDs on, and a  little bit of smoke
[*]removed PC boards again, noticed the swapped transistors
[*]desoldered the wrong transistors from the small and large board, soldered them in the correct location
[*]reassembled, powered on... and here is where it gets weird
[*]
  • Tubes turned on
  • LEDs on the smaller boards were all on
  • LEDs on the large  board were off
  • LEDs and Tube light begin to  slowly fade out until they are completely off

[*]I now can no longer get the Tubes or LEDs to power on

[/list]

I am going to go ahead and assume I fried the 2N2222As and possibly the 2N2907As, is there anything else I should check and/or be worried about? 
 
I would replace all of the transistors on all of the boards.

Generally a swap like this doesn't smoke the amp, so be prepared for additional diagnostics once everything is in its proper place.

-PB
 
Ok, I ordered the transistors.  I am guessing the bit of smoke was from a really bad solder point at 15 that I went back and fixed after my first set of problems.
 
Ok, I replaced all the transistors and the fuse and I have a different result now. 

-left most LEDs off
-bottom right small board's LEDs are both off. 

I have no idea where to go from here.  Picture and voltages below.

Voltages
1 70
2 188
3 16
4 188
5 185
6 0
7 110
8 16
9 186
10 0
11 16
12 0
13 187
14 0
15 206
20 0
21 222

gzfb2CV.jpg

 
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