This diagram was found in the November 1972 issue of Radio Electronics magazine in an article describing benchtop equipment. The transistors are of the time and the frequencies are given by the coils.
Using the LM380, this circuit provides a power of the order of 200 mW. In it we have a stage of...
I found this circuit in an article in a 2003 publication. The circuit is an example of how to...
We found this circuit in a Radio Electronics from October 1965. The pickup coil can be of the...