Super Heterodyne Receiver SW MW LW

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I got 500pf Sanyo Airvariable Capacitor and I want to design a Supeehet radio with today's modern JFET like CPH3910.
I think it is possible to wind Antenna coil & Oscillator coil of radio . Only problem is finding resources on superhet receivers as most hobbyist prefer regen receiver.
It is legacy to have a AM radio in Super Het . I can't find book's in designing superhet receivers , I think no one is interested anymore.

Thanks for reading .
 
For superhet you normally use a dual-gang variable capacitor, I'm sure there are lots of old designs out there, despite being only in old books! The tricky bit is getting good tracking between local oscillator and the input tank using the dual gang cap - usually a bunch of trimmer caps is used to adjust the band ends to match them up. You can make the Q fairly low to get easier tracking at the expense of selectivity.


LO should be 455kHz higher than the RF frequency across the band, use standard mixers and 455kHz IF strip components which should be easy to source or salvage.



Fortunately for AM band the frequency stability requirements are quite lax which will help with the LO design.


A more modern design would use a PLL LO, varicap tuning for the RF preamp and IC mixer like the SE612 (Gilbert cell). For better large signal handling a diode double-balanced mixer would be good, depends if you want to DX or not really.
 
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