Hughes suggests this circuit in a 1968 documentation. The circuit uses old transistors that can be replaced with equivalents. MOSFET is the critical component of the circuit.
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...