Here it is:
Pretty straightforward. The "front end" variable caps and inductors were salvaged from the Zenith chassis. 4.7pF caps were added across L3 & L5 to get the dial to track properly on FM.
The variable inductor in series with the 10.7 MHz resonator was added to get the resonator onto the same frequency as the ceramic filter.
The two SPST switches are sections of the Zenith's rotary AM/FM switch. One section is open on AM and closes to the 5 Volt line on FM. This is applied to the TA2003 IC to switch it over from AM to FM and back.
The other switches in about .05 uF of capacitance on the audio output of the TA2003 (FM De-Emphasis.)
One LM324 section is used as a Baxandall tone circuit that can cut or boost the high and low frequencies by about 8 dB.
The transformer was salvaged from an old Motorola battery charger.
The variable inductor in series with the 10.7 MHz resonator was added to get the resonator onto the same frequency as the ceramic filter.
The two SPST switches are sections of the Zenith's rotary AM/FM switch. One section is open on AM and closes to the 5 Volt line on FM. This is applied to the TA2003 IC to switch it over from AM to FM and back.
The other switches in about .05 uF of capacitance on the audio output of the TA2003 (FM De-Emphasis.)
One LM324 section is used as a Baxandall tone circuit that can cut or boost the high and low frequencies by about 8 dB.
The transformer was salvaged from an old Motorola battery charger.
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