This circuit is from a 1968 Electronic Design. The characteristics of the output transformer are not given and the transistors are of the time. The circuit provides a power of a few watts.
We found this circuit in the Linear Applications Handbook of the National Semiconductor of 1994....
This tone-modulated transmitter was found in recent English documentation. The circuit operates in the 27...
This very low current circuit was found in the April 1995 issue of Electronics Now magazine. The...