Operating at a frequency of around 180 kHz, this transmitter was found in a Science & Electronics of 1970. The coil has 34 turns of 22 wire. The transistor can be the 2N2222.
This circuit is from an Argentine publication from 1973. It generates a 100 kHz signal from a...
This filter was found in a 1975 American technical publication. The filter can be of any type and...
This circuit was found in a 90s American documentation. The circuit uses still common components...