The transistors in this circuit can be the BC548 and it also functions as a logic function. The supply voltage depends on the circuit to be excited.
This circuit recognizes the tone programmed in an oscillator 555 when inserted into a slot that...
This circuit is based on the Texas Instruments LMC662 and has the function of monitoring the audio...
This circuit for crystals from 100 to 500 kHz was found in an American documentation from 1954. The...