This common circuit using operational amplifiers was found in the 1993 issue of Radio Electronics Special Projects. The circuit is sandwiched between the pickup and the amplifier input.
This is the receiver for the CB18476E, but it can be used with other transmitters found on the...
This circuit was found in Radio Electronics from the 90s. The CMOS integrated circuit is a PLL not...
This circuit was found in a 1990 Electronics World magazine. The circuit can be mounted today by...