Early in 1925 Radio Corporation of America station 1XAO had one near
10 mile long wave antenna. In 1926 they had three spaced 6 miles each.
Harold H. Beverage discovered diversity reception when switching
between antennas. When the signal was fading on one, it could be
peaking on another.
AT&T Houlton, Maine used four for trans-Atlantic reception. Above
gain, better antenna patterns, QSB was minimized.
http://www.state.me.us/newsletter/dec2003/radio_free_belfast_maine.htm
73
Bruce-k1fz
On Mon, 28 Dec 2015 09:30:17 -0800, Tree wrote:
Add me to the list of diversity operators. I typically have one beverage
in one ear and some other directional antenna in the other. For the Stew -
this was a 1200 foot beverage towards the East coast and a Hi-Z array (4
directions) in the other ear. I would typically have the 4 SQ also East to
help with those QRP stations - and then switch it towards the West when the
JAs are coming through. If a weak station calls - I check the 4 SQ to see
if they are coming in from the North or South. A lot of my W6 QSOs were
with stations using marginal antennas and they are pretty weak when things
are pointing East.
At my previous QTH - I had five directions covered by beverages and I could
quickly switch directions using a control box with momentary pushbuttons:
http://www.kkn.net/n6tr/160/bev/BevBox2.jpg (shown before I got my K3).
With the antennas both East - the signals float around inside my head as
QSB happens. I typically find that with one antenna - I often miss part of
a callsign with QSB - but with two - I can often get all of the call the
first time. This is very noticeable on 80 meters when working Japan.
Tree N6TR
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