Voltage sag control question.

[artofharmony]

Carbon track pots can't handle much current, so if the circuit draws enough milliamps, you can easily burn holes in the pot track. 0.125W is fairly common as a maximum rating, and that's only 14mA at 9V.

Ah makes sense. If the current draw is coming from the circuit, it will be limited by the current draw of the circuit. If the current draw going through a pot straight to ground, there's WAY more current. I did that to a pot on the emitter of a transistor once 

[ElectricDruid]

If the current draw is coming from the circuit, it will be limited by the current draw of the circuit.

Yes. This is usually the problem. As you push "voltage sag" pot up towards the maximum voltage, the remaining little bit of pot track has to handle the entire current of the circuit.

If the current draw going through a pot straight to ground, there's WAY more current. I did that to a pot on the emitter of a transistor once 

This is only a problem if the pot value is small. 9V across a 1K pot is only 9mA so that's "safe", if inadvisable. Any pot value larger than that should be fine.

But yeah, I've smoked a few pots in my time, one way or another. Mostly by not concentrating on what the hell I'm doing 

[drdn0]

If the current draw is coming from the circuit, it will be limited by the current draw of the circuit.

Yes. This is usually the problem. As you push "voltage sag" pot up towards the maximum voltage, the remaining little bit of pot track has to handle the entire current of the circuit.

If the current draw going through a pot straight to ground, there's WAY more current. I did that to a pot on the emitter of a transistor once 

This is only a problem if the pot value is small. 9V across a 1K pot is only 9mA so that's "safe", if inadvisable. Any pot value larger than that should be fine.

But yeah, I've smoked a few pots in my time, one way or another. Mostly by not concentrating on what the hell I'm doing 

And then you find mystery 500k volume pots like this in your passive guitar that have ONLY been used with your pedals/amp. I've still got absolutely ZERO idea what happened here.

[ElectricDruid]

And then you find mystery 500k volume pots like this in your passive guitar that have ONLY been used with your pedals/amp. I've still got absolutely ZERO idea what happened here.

A powerful bolt of inspiration burned through your guitar?!? 

[bluebunny]

A powerful bolt of inspiration burned through your guitar?!?