This circuit, found in a 1977 documentation, indicates when the grid voltage goes through zero. Under these conditions, it produces an output pulse whose duration depends on the capacitor.
Other operational amplifiers can be used in this conventional filter that rejects only one...
The integrated circuit used in this' 90s amplifier is not very common today. The supply is 24 V,...
This squelch circuit is placed at the input of the single receiver audio amplifier stage. Its...