"Lisa Simpson" ) writes:
It makes perfect sense to have to guess at, or calculate, the frequency
you're tuned to, when it would have been just as easy to actually display
the actual frequency you're listening to?

Assuming you are talking about radios without digital displays, I should
point out that they weren't left off old radios for some vague reason.

They were left off because digital displays would require a huge chassis
for all the tubes to make the digital display, and of course that would
drive up the cost so it would be beyond the means of most people.

You could go with a mechanical digital dial, but you then either have
the National HRO (complete with plug-in coils for each band) which
was expensive, but still didn't give linear readout. It cost too
much, and was too complicated, to make each band linear, so the
fine numbers on the dial were just really good logging scales (and
reasonably decent readout).

There were expensive receivers like the R390 that had mechanical
digital dials. They fixed the problem by having the dial cover a fixed
and small range (500KHz), and then adding a converter ahead of it
to get all the bands. It was much easier to get linear tuning,
so the digital dial reflected the frequency accurately, with such
a scheme. But it cost money to pay people to get the tuning linear,
and thus no hobbyist could afford those receivers until they were
available in surplus.

Note that the same scheme did provide pretty good dials without
the mechanical digital readout. But again, it was far easier to
calibrate the dial every 1KHz (and be accurate) when the tuning
only covered a small range and didn't change when the band changed.

In the old days, dial accuracy and precision went up the more you
spent on a receiver.

What's misleading is that solid state electronics have made digital
dials easy and cheap and small, so much so that it's now easier
to use them than trying to do an analog dial. But just because
a receiver has a digital readout now doesn't actually mean it's a good
receiver. They are just as bad as the low end receivers of decades
ago, albeit with a better dial.

A good receiver can be expensive.

Michael