Is this a transmitter? Medium-wave short-wave consists of three transistors. The transistor AF115, along with the rest of its circuitry, is the oscillator of the device. The circuit of the two OC72 is the low-frequency amplifier (modulator), which forms the carrier wave produced in the circuit of the AF115 lamp from its secondary transformer T1. The microphone is crystalline of small size. Transformer T1 is an adapter and has AD9014 data.
The L1 coil consists of 60 coils wrapped on a core of ferromagnetic material. The wire has a diameter of 0.2mm. Coil L2 consists of 10 coils wrapped on the same core above L1. When the construction is finished and the oscillation (load-generating device) does not work, then disconnect the ends of the coil L2 and connect them backwards.
Capacitor C1 is either a small variable of 300-500pF or even 500pF. The antenna of this transmitter is a foldable length of one meter With careful construction, this transmitter at mid waves reaches exactly 50 meters. If we want to shape the oscillator carrier wave with music from an active source, then the circuit of the two OC72 (low frequency amplifier) including the T1 is over.