I finished my Crack build a couple of nights ago and both the resistance checks and voltage checks were fine. I fired up the amp and listened to it for about an hour and everything sounded great. I flipped the switch today, two days later, and the amp would not turn on. The tubes weren't glowing and the LEDs on the bottom of the A socket were not lit.
I did a resistance check and all checked out. I did a voltage check and was getting very high voltage readings on the terminals that should have voltage on terminal 1-6 as shown below. I wasn't getting any voltage on terminals 7 and 9. When I got to terminal 13 and 15, they were also reading high. On a second reading of terminal 15, I must have shorted something with the probe as there was a pop and spark at the cap.
Terminal voltage
1 224
2 230
3 0
4 229
5 225
6 0
7 0
8 0
9 0
10 0
11 0
12 0
13 230
14 0
15 229
After the spark, I repeated my voltage measurements and now, all the voltages are low and falling as I continue to probe through the board. They started at about 11V, and by the time I got to the end of the measurement, the terminals were all showing 0 volts. Terminals 7 and 9 were still showing zero when others were showing less than 1V.
1 11.2
2 10.4
3 0
4 9.4 and dropping
5 8.4 and dropping
6 0
7 0
8 0
9 0
10 0
11 0
12 0
13 3.8
14 0
15 0.5
20 0
21 0.6
a1 0.7
a2 0
a4 0
a5 0
a6 0.5
a7 0
a9 0
b1 0.4
b2 0
b3 0
b4 0.4
b5 0.4
b6 0
b7 0
b8 0
Any ideas what might be wrong? I've checked out all the diodes with the meter and they all check fine. Caps are all oriented correctly. Everything was working great for an hour!
