This simple receiver AF amplifier can supply several hundred milliwatts to an 8- speaker. The gain is about 200X. If
high gain is not needed, C2 can be deleted and a gain of 20 will be obtained. R1 and C6 are musts, otherwise ultrasonic (30 to 60 kHz) oscillations might occur. C6 can be 0.1 Â¥ on all LM386N versions for protection against these oscillations. The supply voltage is typically 6 to 12 V. No heatsink is necessary, but good grounding is a must.