This is design for antenna booster circuit. This circuit can be used to amplify the weak signal received by the antenna. This circuit is a simplest form of circuit. Antenna for AM/FM is usually not tuned for the optimal dimension of 1/4 wavelength, since we prefer small portable size. This is the figure of the circuit.
Use around 470uH coil for L1 if you use for AM frequency (700 KHz - 1.5 MHz) and use around 20uH for SW or FM receiver. For short wave performance, using this antenna booster, you’ll get a strong signal as we get from a 20-30 feet antenna, with only a standard 18″ telescopic antenna and this booster circuit. The power supply should be bypassed by a 47nF capacitor to ground, at a point that should be chosen as close as possible to L1.
Use around 470uH coil for L1 if you use for AM frequency (700 KHz - 1.5 MHz) and use around 20uH for SW or FM receiver. For short wave performance, using this antenna booster, you’ll get a strong signal as we get from a 20-30 feet antenna, with only a standard 18″ telescopic antenna and this booster circuit. The power supply should be bypassed by a 47nF capacitor to ground, at a point that should be chosen as close as possible to L1.
