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From: "Alan Melia" <alan.melia@btinternet.com>
To: <rsgb_lf_group@blacksheep.org>
References: <PAEFLMFGBDKKCONLMLBIIECCEHAA.ganymede444@btopenworld.com>, <3E2191D6995647D48932529876C7636C@gnat> <53AC1579.29762.C84E42@mike.dennison.ntlworld.com>
Date: Thu, 26 Jun 2014 14:08:39 +0100
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Subject: LF: Re: RE: Summer Solstice Test report
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Hi Mike well at  137 the daytime signal is skywave over about 700km I 
watched Budapest (about 1200km) and there is a distinct "dome" in the 
response at local noon at mid path. This is higher in summer as the sun is 
higher and so stronger. I think on 472 the ground-wave is shorter 
particularly at our power and aerial situations, and I suspect the skywave 
though there may not be as predominant as at 137. .....more day-time 
absorption. I am sure the local environment, trees building etc has an 
effect too.

Alan

----- Original Message ----- 
From: "Mike Dennison" <mike.dennison@ntlworld.com>
To: <rsgb_lf_group@blacksheep.org>; <rsgb_lf_group@yahoogroups.co.uk>
Sent: Thursday, June 26, 2014 12:43 PM
Subject: LF: RE: Summer Solstice Test report


> On 25 Jun 2014 at 21:55, Alan Melia wrote:
>>
>> It is interesting that there does seem to be a suggestion that 137
>> holds up better in summer than 472.......have I read that correctly,
>> or maybe it was from another poster. I was not able to do the same
>> sort of tests for 472.
>
>
> I haven't done any scientific tests, but from a lot of monitoring it
> seems that for daytime ranges around 500-1000km 136kHz works better
> than 472kHz. I presume this because the 136kHz daytime propagation
> over this distance is primarily by ground wave, whereas on 472kHz the
> ground wave range is less so sky-wave is needed and this is not
> available until dusk.
>
> It is difficult to compare the two bands over longer distances
> because 472kHz is not available in Russia (unlike 136kHz), and
> activity seems low in many other countries.
>
> 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?
>
> de Mike, G3XDV
> ============
>