'''What do others know about the ground wave range in summer and in the
afternoon? When does the band open? Similar to LF?''
Stefan, Ground range is really a product of erp + data processing (if
your are digital) , 75 miles is about the saturation range , you may
remember the 'Beacon Bedlam' when 500 was first allocated and lots of
qrss beacons where established (Luckily Myself and Gray are over 100
miles north of know end of civilisation Watford-gap and missed out on
this !)
Next is the skip round 175/ 250 miles , there seemed to be a belt
round that distance that was always difficult to work, then next 300
miles + in the night
There where a good set of propagation/ time delay / phase plots on
the old uk500khz web site using the ZL psk-software , showing the
phase distortion at times of qsb on 500 , that gave a indication as to
why psk-31 was all ways a very poor mode over distance ,
This plot from DK8KW , with one long run of the Op beacon , gives a
good over view of the changes of conditions over the night , I only
started to decode off air quite late on , But I could copy your CW
much earlier in the night, so I assume the station is working correctly
, but later decodes are many dB down on the South Uk levels , but
skip may of been the simple reason , I was using a 40ft x 2 inch end
fed vertical mast , 6 ft off the ground, at the time , with only the
pre-selector in the Rx as the tuner
73 -G..
http://uk.groups.yahoo.com/group/rsgb_lf_group/photos/album/96277963/pic/1714843914/view?picmode=&mode=tn&order=ordinal&start=1&count=20&dir=asc
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From: "Stefan Schäfer" <[email protected]>
Sent: Sunday, June 17, 2012 3:03 PM
To: <[email protected]>
Subject: LF: Further MF impressions
MF,
I just thought my receiver isn't working correctly. I thought the xtal
does not start to oscillate due to the higher ambient temperatures in the
afternoon. But later i found that the band noise on MF is significantly
lower than in the evening, at least 20 dB. So now i see that the band
noise is about 5 dB above my soundcard noise with the current setup.
What do others know about the ground wave range in summer and in the
afternoon? When does the band open? Similar to LF?
BTW thanks to DF6NM for the grabber. Nice tool to get some experience in
these first days...
73, Stefan/DK7FC
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