We also live in the wrong place , propagation seems to be better in
the south , most marine 500 sets only run 100/200 watts on 500k ,
the emergency sets round 50 watts
Standard Ae , marine set up has the classic 40/60 ft vertical
section and 120 ft top , feed point is 80 ft above sea level , the
hull is steel , evolved 'ideal' Ae 1000 to 2000 miles range
expected norm
Sea water is the big thing , last 500k dx emergency was from
south to north pacific , and that was after the 500 band had been
removed from service , apparently the ship still had the radio
room , it was broken into and as a last chance , managed to raise some
one on 500 - usa I think
100 miles of land makes a big difference , I can work in GI/EI no
problem , as can G3KEV work in to EU from the east coast , I need
about 250/300 watts to decode OP4 via the tween web sdr in the day
, that's 350 miles , about 50 over sea , conversely 50 watts pep ssb
is 5/9 into Belfast
One of the problems associated with the wspr decode , is strong
carriers in the pass band , which raise the minimum s/n decode level
, you can see that when a strong local station runs up , the spots
in its locality [75 mile radius] , higher power levels have larger
ranges .. 'we on 500 had the advantage of minimal activity , so DX
decodes where more achievable back then , wspr was designed for HF ,
where high level ground wave signals are not encountered at range .
G,
--------------------------------------------------
From: "DK7FC" <[email protected]>
Sent: Thursday, June 26, 2014 1:33 PM
To: <[email protected]>
Subject: Re: LF: RE: Summer Solstice Test report
Hello Mike,
Am 26.06.2014 13:43, schrieb Mike Dennison:
Personally, I have been disappointed by the amount of DX received
during darkness hours on 472kHz so far. It seems commonplace
to receive stations out to Scandinavia and Italy, but little beyond.
Yes, I have seen some transatlantic DX but nothing to match
the stories of worldwide openings reported by retired marine 500kHz
operators, or indeed what is availalable routinely on 160m. Is this
just lack of activity?
It is lack of RF power for many stations!
Furthermore there is a big difference between 2200m and 630m regarding
propagation above sea water and above land. There have been just a few
WSPR decodes on 630m by russian RX stations while they are getting very
good results on 2200m. That explaines the advantage of living near the
sea. In other words, it should be relatively "easy" to get some TA
detections by stations living near the sea, however it is much harder to
get the same results when living a few 100 km distant from the sea...
73, Stefan
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