This circuit was found in a 1980s documentation. The diodes may be general purpose diodes such as 1N34 or 1N60 and the indicator may be the lowest current range of a multimeter.
The quiescent current of the small transmitter is around 20 mA. The transmission frequency depends on...
Based on common unijunction transistors, this 1968 General Electric circuit is powered by 12 V. |...
This circuit was found in a Texas Instruments documentation from the 1980s. The circuit monitors...