This circuit limits the intensity of an audio signal from a control voltage. The circuit is from a 90’s Radio Electronics. The coupler is a type that uses LDR.
This circuit was found in a Mullard transistor manual from 1960. Note the symmetrical power...
This amplifier step with a transistor has an input impedance of 100k to 10 M. The transistor can be any...
I found this little signaling transmitter in old American documentation. The circuit has a good...