I welcome everyone!
I made the bias of my microphone (based on the Cad Trion 8000) according to this scheme.
Everything is fine, but there is a hum and noise.
When I turn off the power supply of the microphone, the noise and hum disappear (until the filter capacitors in the power supply are discharged - this is an ordinary Chinese power supply). Its circuit and voltages are in the image.
I understand that the heating voltage is poorly filtered.
How can you filter-smooth the heating voltage well so that remove the hum and noise, maybe use lm317 instead of 7806?
I made the bias of my microphone (based on the Cad Trion 8000) according to this scheme.
Everything is fine, but there is a hum and noise.
When I turn off the power supply of the microphone, the noise and hum disappear (until the filter capacitors in the power supply are discharged - this is an ordinary Chinese power supply). Its circuit and voltages are in the image.
I understand that the heating voltage is poorly filtered.
How can you filter-smooth the heating voltage well so that remove the hum and noise, maybe use lm317 instead of 7806?