We're now going to broadcast an organ melody and receive it on an AM radio set. In this experiment also we need to find the quiet spot on the AM band.
The schematic shows you that NAND gate CMOS ICs are used for oscillation and modulation. The organ melody is produced by UA and UB.
You can make different notes organ by turning S1 - S8 ON one by one. UC produces an AM broadcast frequency, and UD works as a modulator. You can change the frequency with the tuning control.