[R-390] Space diversity reception

[Tisha Hayes]

You can get an idea of how diversity receivers worked if you look at the
Hamamrlund SP-600, JX17 mod. That receiver had an additional front-panel
switch and additional settings on two other positions for diversity pairing
with a second JX17.

What they did was to share a common oscillator so frequency tracking and
phase relationship was the same.

I believe that there were mods to the R-390 (A?) that also allowed for
diversity-pairing.That might have been a NASA-mod (memory recall).

There might be some complications from the Collins mechanical filters
(altering phase relationship). But that is just my opinion.

You would need a set of cabling and jacks for common oscillators.

++++
I do true diversity reception on a different model of radio but in my case
it is polarization diversity with wellbrook loop antennas where I rotated
one 90 degrees (side feed instead of base feed). The antennas are almost 20
meters apart and I feed the two receivers into different ears on a pair of
stereo headphones. It is kind of trippy to hear the signal flutter from one
side to the other in my ears as propagation conditions change.


*Ms. Tisha Hayes, AA4HA*

"*We live in accordance with the flow of the times*"
-Yoshio Mizuno