TOM WALKER wrote in a message to ROY J. TELLASON:

RJT> MR> IIRC before the advent of digital synthesized tuners in car radios,
RJT> MR> tuning was done using inductive coils into which a ferrite piston
RJT> MR> would be inserted or extracted, instead of the usual tuning
RJT> MR> capacitor.

RJT>I've only ever seen that in car radios,  myself.

 TW> I am thinking the same thing. BUT far back i nthe Fuzzy brain I
 TW> think I ran across a Tavble radio that used it. IT woudlc have been
 TW> only in a Higher priced model though as it was more expensive to
 TW> produce. The reason morotols used it in teir Car Radios is bacuse
 TW> they came up with a clever way to change stations with One button.
 TW> There was a 6 volt solenoid and a ratcheting mechinism that gave
 TW> you six positions for hte Coil slugs.

That whole thing with the presets was something I never did get much of a
handle on,  the way it worked...

And now,  of course,  we've got *electronic* presets,  usually with no
backup for the "memory" in there,  so if you have to disconnect
the battery for some reason you have to put 'em in all over again.  This is
progress?

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