[ARC5] How Edwin Armstrong invented the superhet (according to Wikipedia)

[Leslie Smith]

Hello all:
First, I made a mistake by only quoting Wikipedia in part.  The article is
much longer than the fragment I posted here.  My mistake, please excuse
me.  Please follow the link I provided to the full article.

Next, my interest was in the development of the superhet, from (I guess)
about 1915 to when it  became the dominant technology (so let's say until
the time Drake designed the "K" series).  Somewhere around 1931 .. 1934.

I found other references (ie not Wikipedia) that recounted (in outline) the
same history I read in Wikipedia.  As others wrote here: radio direction
finding depends primarily on measuring angle, not signal strength.

On a side issue (RDF related):  Beryl Oliver (I knew her son a little) told
me she approached the military at the beginning of WWII to work in signals
(or radio).  They told her: go to the local postmaster.  Learn morse.  When
you can send/receive morse at 17wpm come back here.  She worked in RDF.  I
don't know if this was RAAF or navy.   I recall seeing a photo of her
standing beside an impressive console in uniform.  She told me aircraft
would contact her (when lost) and ask for a bearing.  She would reply.  At
times (she told me) she told them:  Continue to fly on (some course).  I
will tell you when you are over my station.  (She told me the signal
dropped to a minimum when the aircraft was overhead.)  She also told me she
was one of several stations engaged in tracking the IJN.   I greatly regret
not recording these conversations.

Radio technology was primitive during WWI.  In our local radio club library
we have a set of admiralty books where capacitance is measured in 'jars'.
As I understand it, a Leyden jar has a capacity between 1 to 2 nF.

73 to all from VK

Leslie
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