Posted on Aug 4, 2012

The local oscillator is crystal-controlled and the i-f swing is hardly compressed. The deviation of the transmitted carrier frequency, because of modulation, must therefore be limited to prevent severe distortion of the demodulated audio signal. The component values result in an i-f of 4.5 kHz and an i-f bandwidth of 5kHz. If the i-f is multiplied ll`f N, the values of capacitors Cl7 and Cl8 in the all-pass filters, and the values of illter capacitors C7, CS, ClO, Cll, and Cl2 must be multiplied by 1/N.

Click here to download the full size of the above Circuit.

For improved i-f selectivity to achieve greater adjacent channel attenuation, second-order networks can be used in place of ClO and Cll.

Leave Comment

characters left:

New Circuits



Popular Circuits

Battery Charger
Digital Thermometer
Wireless doorbell 300MHz
Light-seeking robot
Basement LEDs
10 Band Graphic Equalizer Circuit
Water Level Sensor Circuit Using LM1830 Single Chip
active filters
Space Horticulture Circuit
Vibration Detector Circuit
A non-contact automatic flashing lights circuit
NOT circuit