Re: FRG-7. Very quiet
10Mhz crystals are cheaper but you can usually get them at better stability.
The bandchange switch and what you've called the peaking control are the range and tuning controls for a basic preselector. The preselector is needed to protect a fairly soft mixer from strong signals away from your wanted frequency.... Even the Racals relied a lot on their preselector.
You do indeed set the MHz dial appropriately then tune the kHz dial, but, go back to the MHz dial and twiddle slightly to peak your wanted signal. This dial being off a bit is usually NOT the crystal, but a tuning error in the Wadley system filters. There are two of them and famously a nightmare to adjust. on't touch them unless you really really need to. to adjust them you need a sweeper (wobbulator) and some experience in adjusting higher order filters.
David
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Can't afford the volcanic island yet, but the plans for my monorail and the goons' uniforms are done
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