Much of the discussion on NVIS term origin has been handled before on
the NVIS reflector.
The British were using NVIS in Malaya during the Emergency there, from
the post world war II time to 1963 and in governement dept. comms in
1967. Later from the Malayan armed forces uses, US Forces were
experimenting with it in Viet Nam jungle conditions; as the Brits found
it worked so well in jungle communications, especially around 4 MHz.
The terminology may not have been used in its earliest days being called
"short range HF comms" instead.
The Germans were certainly using it in WW2. Their command vehicles had
a grid or frame antenna structure, low enough to clear low trees, but
most likely single wire fed from the pictures we can find on the web.
Thus, the "antenna" was a kind of tuned almost isotropic radiator. But
since it had considerable horizontal radiating parts, it clearly
activated an NVIS mode, perhaps the low antenna was more of a
convenience over whips when transiting forests.
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