This circuit was found in a 1968’s Motorola documentation. The transistor is from that time. The load can have resistances between 10 and 80ohm.
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...