AM Radio Receiver Circuit Employs FM IC Chip
This AM receiver consists of a TDA7000 single-chip FM receiver (U1) as the main radio component, and an LM386 chip for low-voltage audio-power amplifier (U2) circuit. The receiving coils are hand-wound coils (L1 and L2), and a few additional components. This coils, together with the variable capacitor, is chosen to match the AM frequency. To wind your won coil, L1 and L2 are 100 turns of #28 wire on toroidal cores (about 240 μH each). At 30 turns, L1 is tapped . Here is the schematic diagram of the circuit:
[Circuit’s schematic diagram source: seekic.com]