The method I have used is similar to what Tom details in some respects.
The main RX is fixed in a prime direction, usually NE and later W.
However, the sub-RX is typically on auto-scan between transmissions
(controller detects PTT), hopping through antennas in a specific group,
either beverage or 8-circle directions, with 700-800 ms pause per
antenna. The custom controllers I use allow me to select what antennas
I want included in a scan sequence by manually selecting the antenna and
tapping a "scan-select" toggle button. It makes for a more efficient
sweep of the compass, ie. usually skip N since most stations N of here
are VE and heard just as well on some other antenna, sometimes other
directions skipped based on time of night.
My controllers use an encoder for antenna selection, so it's like
rotating a VFO knob. A slight turn will stop scanning, and makes going
backwards easy if something was heard and scanning overshoots.
One of the more useful features I added was "tracking". When in
tracking mode, the controller will force the opposite receiver to
connect to an antenna in the same direction as the "tracked" receiver
and continue to track direction as long as there is an available antenna
in the same direction as the "tracked" RX selection. For my station,
that means beverage array in one ear and 8-circle in the other. A good
example would be hearing a weak QRP K9YC on the sub-RX while scanning
through beverages. Scanning might overshoot to NW bev, slight manual
knob rotation counterclockwise stops scanning and goes back to W bev,
single tap the sub-RX tracking button to force main-RX selection to W
direction on the 8-circle array. Now listening West in stereo
diversity. Couple more taps and back to original antenna in one ear and
back to scanning in the other.
73 - Eric NO3M
On 2/5/2013 17:42, Tom W8JI wrote:
Out of curiosity... with so many narrow-pattern receive antenna
configs, how do typical contest stations check different directions
after a CQ? Frank, I still want to come visit your station during a
test and see how it all works.
Diversity and stereo headphones gets you to two different directions
but I wonder if there's some more powerful technique.
Not from here, except having more ears on the ground with independent
controls. Each operator has two ears.
I have switches that lock one ear in a prime direction like NE, and
the other ear can go some other direction (at some loss in really weak
signal copy).
It is always a real problem remembering to use things at the max
(stereo and same direction with wide array separation) and to always
remember to change directions often. This is always a problem with 8
directions.
http://www.w8ji.com/my_shack.htm
Over the years, off and on, I have tried to use "auto scanners". My
first was around 1980, and I've tried off and on since, but it just
has not worked so well unless very few people are calling and those
that do call keep trying. By far the best system is just popping the
buttons around to likely directions, although I do have an idea to
double the odds of getting lucky. The problem is getting trained in
how to lock on a signal fast when it is heard.
One real problem is that listening in multiple directions hurts the
copy of noise floor or weaker signals. Stereo with widely separated
antennas is good for maybe 3-6 dB in perception of signals in noise if
the operator is trained to use stereo.
Missing callers, unless the operator scans and the caller is
persistent, is inevitable.
73 Tom
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Topband Reflector
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