[Elecraft] The Old Days

[Nate Bargmann]

* On 2013 29 Jan 14:34 -0600, Sandy wrote:
 
> "Ancient AM" is still used today, but basically only for two
> purposes.  One is AM broadcasting from about 550-1700 Khz.  A
> holdover from "ancient times" dying but "still alive and kicking"
> Second it is used for aircraft communication from about 108-135 Mhz
> or so.  An ESSENTIAL to safe airborne communications and safety.
> The military still uses it in the 225-400 Mhz band in mostly jet
> aircraft.  WHY not SSB or FM?  well because it "does the job" and it
> is reliable and the circuitry is much simpler!

The conclusion here may well be part of it.  A coworker who worked in
avionics in a former life told me that the use of AM for aircraft
communications is indeed for the ease of tuning but also because a
weaker station can be heard under a stronger one unlike with FM and its
capture effect (likely true for digital).  AM allows an air controller
or other aircraft to hear an emergency call when another station is
transmitting.  Based on my experience, I have no reason to doubt his
conclusion.

73, de Nate, N0NB >>

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