This is my first question ever so please don't kill me :)
(the pictures are from the manual that came with the kit, please don't mind the Czech headers)
Parameters for the circuit (from the manual) are:
- Us power supply voltage: 8-28V (I use 9V power supply)
- Peak output current Io (freq. >= 20Hz): 3.5A
- ...and more but IMHO (now) not important values
Now, everything worked great (although I had to replace the C8 capacitor, no idea why it was broken), so I decided I want to replace the R1 and R3 resistors with a potentiometer for variable gain (gain control). I bought stereo potentiometer, linear, 1kOhm, wired it up to R1s and R3s place (first pin ground, second and third pin to the PCB). When I turned the circuit on, the pot started smoking and burned.
If I get it right, I understand that the potentiometer couldn't handle the load when set to little resistance. I didn't really had a choice when selecting the pot as the one I used was the only stereo 1kOhm pot they had in the shop.
So I need to know:
- Is my approach correct here? Can I replace the two resistors with a stereo pot?
- Am I right thinking that the pot couldn't handle the current/load, or was it just a bad piece?
- How do I calculate the power that can be on the resistance R1/R3?
Thank you for help!