This is a field strength meter found in an 80's Hands On. The circuit operates at frequencies up to 500 MHz and has a buzzer as its indicator. Can be used as a detector for spy transmitters.
This circuit allows the use of headphones and microphones with diverse characteristics in audio...
This amplifier with an OTA has a gain of 40 dB. The power supply must be symmetrical. Found in...
Found in a Linear Technology 80s integrated circuit manual this circuit has its gain controlled from...