On Apr 20, 3:44*pm, John Larkin
wrote:
On Mon, 20 Apr 2009 12:23:53 -0700 (PDT), Tim Shoppa





wrote:
On Apr 20, 1:10*pm, John Larkin
wrote:
On Mon, 20 Apr 2009 09:50:05 -0700 (PDT), Tim Shoppa

wrote:
A terminology question I suppose about the derivation of the term
"Superheterodyne" more than anything else:

Does the "Super" actually mean anything? Is there a Subheterodyne?

Traditionally superhets mix a higher radio frequency down to a lower
IF frequency, but certainly in the past few decades radios with IF's
above the RF frequency have become very common in broadband
applications, and those are still called superhets, not subhets :-).

Google turns up a couple hits on subheterodyne but other than one that
might mean "IF higher in frequency than RF" I don't recognize what
they mean..

I suspect that "Super" was more a marketing term than anything
else :-).

Tim N3QE

Supersonic.

http://en.wikipedia.org/wiki/Superheterodyne_receiver

I saw that in Wikipedia too. I didn't believe it, it doesn't make
sense. Why not just call all radio frequencies and IF frequencies
above 20kHz "supersonic"? Then all radios (*) are supersonic, and
we're back to super meaning nothing at all.

Possibly because heterodyne receivers mixed to sonic frequencies.

I didn't really trust Wikipedia on this (it uses unusual language to
talk about perfectly conventional subjects) but I did find my December
1922 QST, and it says (page 11):

In December, 1919, Major E. H. Armstrong gave
publicity to an indirect method of obtaining
short-wave amplification, called the Super-
Heterodyne. The idea is to reduce the incoming
frequency which may be, say 1,500,000 cycles
(200 meters), to some suitable super-audible
frequency which can be amplified efficiently, then
passing this current through a radio frequency
amplifier and finally rectifying and carrying on
to one or two stages of audio frequency
amplification.

To me that sounds a little less awkward and more natural than the
derivation that Wikipedia tries to draw.

Tim N3QE