I'm in the process of building my second Crack kit and have run into a problem. I completed the circuit and both the resistance and voltage checks are within 10-15% of those listed; the numbers can be seen below. The voltage of the headphone TRS jack gets up to 7.7V on startup so that is also normal. After powering it on, there is constant and fairly loud buzzing as well as some occasional crackling. Plugging my headphones into the TRS jack does result in loud popping each time it goes past a ring terminal. The buzzing stays the same regardless of the volume level. I replaced the tubes and the problem was unchanged. I also tried a different power cord and that made no difference.
Whether or not the RCA cables are plugged in makes no difference either. When testing audio, the sound is very clear and the only problem continues to be the loud buzzing in the background (it stays in the background as opposed to affecting the audio being played through the amp). I tested all the grounds listed in the stickied thread and all of them read 0 other than Terminal 4: with one grounding point clipped to terminal 3, as instructed in that thread, and the other on terminal 4, the voltage continues to rise into the hundreds of Kohms.
I'm not sure what the best course of action is for troubleshooting due to the correct resistance and voltage checks. I'm assuming I have a bad resistor; maybe the 22.1K resistor between terminals 4 and 5?
Thanks,
Andrew
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