This circuit is temperature stabilized. Modern equivalent transistors can be used, and the power supply can actually be between 9 and 12 V. The circuit is from an old documentation.
We found this high gain circuit with the LM381 preamplifier in a Radio Electronics from February 1990....
We can produce pulses controlled through this circuit that can function as a shield if powered by a...
If mounted with SMD components, this transmitter will be so small that it can be installed inside a...