This is my first question ever so please don't kill me I have built a stereo hi-fi (end) amplifier 2x10W based on a IC TDA2009. I have bought it as a construction (learning) kit ready to solder. Schematic: (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!
