Message-ID: <003c01c81cca$6c685ed0$0d00000a@AGB>
From: "Graham" <g8fzk@g8fzk.fsnet.co.uk>
To: <rsgb_lf_group@blacksheep.org>
References: <001c01c81c0b$ef981a80$2201a8c0@PC2><E1InMCb-0006LO-Ae@post.thorcom.com><47297997.1208.1CCA4C@dave.davesergeant.com><20071101082740.18172494@lurcher.twatt.local><000d01c81c8e$85911230$0d00000a@AGB> <20071101143241.7af5f29e@saluki.ngw.uk.com>
Date: Thu, 1 Nov 2007 21:01:50 -0000
MIME-Version: 1.0
Subject: Re: LF: RE: 500 kHz report /  Great expectations
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Good point's john .





>>>My point was that Dave has said more than once that he struggles to be
> heard, despite receiving other more distant stations with seeming ease<<<



  But that's   the point, this band demonstrates the concept of 'skip 
distance' quite elegantly, second only to  6 mtrs,  The transmission losses 
at this frequency seen to be quite low, but if your out of the skip distance 
, then even more power will not resolve the situation for semi local 
stations



'We' who live close to  each other either get everything or nothing at all, 
those who live a little  further a field ,no pun intended, will receive 
nearly all stations on a regular basis..



'water water everywhere and not a drop to  drink'





>>>However...on 500kHz the receiving stations are where they are! If you
want to work what you hear you must approach reciprocity of ERP,
considerations of local noise floors aside.<<<





The transmission losses at this frequency seen to be quite low, however, 
domestic generated noise levels appear to  be distortional high, which is 
unfortunate, as the adage goes  'if you can here them, you can work them' 
may not actually stand up to  investigation , path losses may not be 
reciprocal , and the noise floor at the distant station may well be 
significantly higher



For example, the s-meter on my R5003 , is calibrated in sinpo units , 0 > 5 
, connected to  my atu the receiver when in 'usb' (2.4 khz)  reads a 
constant '3' on the meter uniform background noise. The same setup 0.5 / 1 
on 80 mtrs . It would take a significant increase to address this situation, 
which I fear will exist at any 'urban' location.



>>>>We shouldn't be afraid of the engineering needed to generate highish
powers, nor feel that it's against the spirit of QRP to do so.<<<





25 watts looks to  be a reasonable feed to  a small system to  reach 
something in the region of 100mW ,  For a lift of  'one' s-point @ 6dB that's 
up to  100 watts  and as can be observed during the many cw qso's  signal 
outages look to  be in the ratio of approx  3:1 20 seconds good  signal in 
every 60 ,  one  s-point is not going to  decrease that by very much ! dx 
reports have been quite consistent , with good copy , , flutter replacing 
the deep qsb observed at 'close' range.



 May be we should regard this as a 'Digital band' in the true sense of the 
word ..



G ..