This circuit with RIAA equalization is from 1985 US documentation. The circuit has a flat response of 150 Hz to 40 kHz. The power supply must be symmetrical.
This receiver for the police band, which at the time was 45 MHz, was found in a publication by...
The purpose of this circuit is to detect audio that amplitude modulates an RF carrier. The circuit is...
The circuit presented was found in a Texas Instruments optoelectronics manual. The signal must be...