This is a Mini MW (Medium Wave) Transmitter circuit. This circuit consist of combination of transistors SA103 and SA101. Those transistors is used as oscillator and modulation signal amplifier. Here is the schematic diagram of the circuit:

Mini MW Transmitter circuit1 circuit schematic

The transistor is of germanium type, but I think you can replace it with silicon type from the high frequency one. The inductors labeled with 100mA is an RFC (radio frequency choke). The transformer in the final transistor is an audio output transformer, or you can use an an 8 Ohm 1:1 transformer.



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