On Fri, 31 Jan 2020 13:04:22 +0000 (UTC), Brian Reay
wrote:

snip

There are several ICs designed for something similar. I have, or had (I’m
not sure where they are) a couple of cheap ‘Chinese’ radios someone gave me
which were about the size of a match box.

That's the sort of thing I was thinking about.

They had a couple of buttons to
control the volume to a pair of ear phones and a couple to scan.

Yup.

FM only.

All that's needed / wanted in this case. ;-)

I
think the ear phone cable doubled as the antenna.

Yeah, that sounds familiar and was mentioned elsewhere.

I used then while walking
before I bought an iPod.

The case was clearish plastic and, as I recall, there was only one IC and a
few support components inside- plus the batteries.

Ok.

I saw similar ones on sale for a few pounds.

Yup, they are on eBay and the like.

Considering the price/simplicity etc, the performance wasn’t bad- certainly
good enough for casual listening while walking etc.

That's the goal, just for R4 so mostly the spoken word etc.

The only niggle, you had to scan through stations to find the one you
wanted,

And that was the rub and what I was trying to avoid with 'set' tuning
jobby.

although I think I remained tuned to the last one used when turned
off and back on.

Well that would be ok, as long as it didn't also autotune, if it lost
signal for a second (as I think the one I had did).

Try a google for ‘single ic fm receiver’.

I nearly got there when Googling last night but was looking more for
something that was a kit than just a component list, knowing how
'funny' RF can be around component layout.

That said, I was wondering if such a radio could be made stable enough
to stay 'locked' on say 93.2 MHz (R4 off CP?) or would I still need
some sort of user accessible trimmer if not tuner?

If it was locked on one frequency I'm guessing it could then be
optimised for that (a nice high to our 'Q'?). ;-)

Cheers, T i m