Being somewhat of a polymath (just spent all day fence judging
at a horse trial) I find that I have a string of ideas faster than I
could ever implement them (rather unkindly described in one area
as vapourware), but I think it to be useful to punt them for a wider
discussion.

Musing upon the Huff-and-Puff technique, I wondered if there
was a better way to improve the frequency stability of older RXs,
because the Huff-and-Puff necessarily brings about a punctuated
frequency span (eg, multiples of 32 Hz), and this is what I came up with ...

Using the ubiquitous timers to be found en masse in most micros
that seem to sell for only a few pence / cents these days, implement
a frequency counter to measure the local oscillator. Then, when
the user presses a Lock button (yet to be provided) the same micro
can program an si570 to generate the same frequency indefinitely
and to switch the mixer stage from the original to this new oscillator.