This AM receiver classic design, revamped to use a transistor instead of a vacuum tube applies the principles of regenerative receivers which essentially means that the transistor stage has high levels of positive feedback at a certain frequency the frequency of desired tuning. The stage is operated right below the point of oscillation.
In addition to amplifying the signal, the stage also provides the "detector" function.
This am regenerative receiver circuit project use four 1.5 volt battery cells in series as a power source, or, you can use a 6 volt DC battery or even a 9 volt battery .
This am regenerative receiver circuit works over 1000-mile range (around 1600 km) with a four-foot antenna.
L1 coil must have a 36 turns of #22 on a 4-inch form and C6 capacitor must have a value of 365pf (or L1=72 turns; C6=125pf ).
To adjust this am receiver you must tune R1 until oscillation occurs; back off until is ceases. Now tune C6 for a station, retuning R1 as necessary.
This receiver circuit use a LM386 power amplifier IC that drives a small o ohms speaker . If you connect a mother jack connector like in the circuit diagram , you can use a headset speakers .
Adjusting the 50k potentiometer you can control volume .