This circuit is suggested by National Semiconductor in its Linear Applications Handbook. The LM3909 integrated circuit consists of a very low consumption oscillator with a power supply of 1.2 V.
This circuit transmits the sound signals from a television or amplifier to an FM receiver at up to...
This is one of the first games that came out in the 70s. This one is from a Radio Electronics...
We found this circuit in an old American documentation. The operational amplifier is not common...