This circuit was found in a 1965 Radio Shack documentation. The transistors are from that time. The circuit can be implemented with current transistors and lower voltage supply.
This simple transmitter for the AM range was found in a Popular Electronics magazine from March...
This double time constant circuit for resistive loads was found in documentation from the 1980s. The...
This circuit was found in a Popular Electronics from the 90s. The components used are all common...