Shorted Resistor [resolved]

[MilderER]

Hi again. While doing a voltage check on terminal 3, I committed the rookie mistake of allowing a clip lead to slip off the terminal and accidentally touch a second terminal (or more likely another lead?). The moment it happened, I heard a loud hiss/pop; a burnt smell wafted into my nostrils soon thereafter. I immediately shut off the power and feared I'd destroyed the amp.

In an effort to assess the damage, I've (1) tested the fuse (still good), (2) rerun all resistance checks (still good), (3) checked continuity of the 22.1K resistor and all connected wires (no issues), (4) measured the 22.1K resistor and the 10W (both fine), and (5) checked that the LEDs are still intact (they are).

So is it safe to plug the amp back in and continue with voltage checks (since I haven't plugged the amp back in, I don't know whether the tubes still glow when plugged in; what if they don't?)? Does the burnt but seemingly functional resistor need to be replaced? Are there any other safety checks I need to perform?

Thanks as always for help and advice!

-Jonathan

[Paul Birkeland]

Yes, you can continue with voltage measurements.

[MilderER]

Thanks for the reassurance, Paul; without your help in particular, there's no way an ignoramus like myself would have gotten this far. I went ahead with the voltage checks and all the numbers looked good. I was worried I'd blown out the tubes when I shorted the amp, but they seem to light up just fine. Tomorrow, I'll plug in some garbage headphones to see if can't get some sounds out this thing. For tonight, I'm just going to admire those tubes.

-Jonathan