This is a simple DOA - transformer in/out NFB Gain...
I get this strange whistling/ noisy thing about have way through the turn of my gain pot. It goes away the higher or lower I turn it... seems to be some particular resistance that causes some kinda feedback or oscillations in the op-amp?
Schematic included... http://i907.photobucket.com/albums/ac273/jwhmca/700MICPREC.jpg
Any thoughts?
I get this strange whistling/ noisy thing about have way through the turn of my gain pot. It goes away the higher or lower I turn it... seems to be some particular resistance that causes some kinda feedback or oscillations in the op-amp?
Schematic included... http://i907.photobucket.com/albums/ac273/jwhmca/700MICPREC.jpg
Any thoughts?