This circuit was found in an Electronic Design from 1964. The components are from that time and can be replaced by equivalents. The modulation ranges from 0.25 to 0.75 of the 20 kHz pulses.
In need of a small amplifying stage for an intercom, radio or other type of device powered by...
In the circuit that uses a PIC16F84, the audio present at the input will have its level controlled by...
We found this circuit in a Philips documentation from 1965. The circuit uses a common LDR sensor...