This 5.1 MHz circuit was found in a 1980s documentation. The frequency is given by the crystal and general purpose transistors can be used.
This unijunction transistor oscillator is intended for Morse code practice. The circuit is from an...
This basic tone control circuit employs a Philips NE5538 operational amplifier, but can be adapted to work...
August 2016 - It can be obtained from Mouser Electronics MDS adapters for medical use from Delta...