Received-SPF: neutral (google.com: 193.82.116.20 is neither permitted nor denied by best guess record for domain of owner-rsgb_lf_group@blacksheep.org) client-ip=193.82.116.20;
Date: Tue, 14 Aug 2007 18:16:40 +0100
From: John Pumford-Green GM4SLV <gm4slv@sighthound.demon.co.uk>
To: rsgb_lf_group@blacksheep.org
Message-ID: <20070814181640.6c234777@lurcher.twatt.local>
In-Reply-To: <46C1A991.50309@yahoo.com>
References: <Pine.LNX.4.64.0708141100010.10082@lurcher.twatt.local>
	<46C1A991.50309@yahoo.com>
Organization: The Gammy Bird
Mime-Version: 1.0
Subject: Re: LF: QRP Experiments
Content-Type: text/plain; charset=US-ASCII
Content-Transfer-Encoding: 7bit
Sender: owner-rsgb_lf_group@blacksheep.org
Precedence: bulk
Reply-To: rsgb_lf_group@blacksheep.org
Status: O

On Tue, 14 Aug 2007 08:09:37 -0500
WE0H <we0h@yahoo.com> wrote:

> Hi John,
> 
> What distance was that QSO with Finbar & what antennas do you guys
> run? Lightning static is causing us lots of trouble here in the USA
> on 505kc. It is usually 40/9 noise floor as we keep getting
> thunderstorms across the country every night.


Hi Mike,

Finbar and I are approx 420 miles apart. I'm in the Shetland Islands at
IP90gg and he's in Northern Ireland, I think his locator is IO64ix. 

The path between us is partly sea (as you'd imagine - with me being on
a remote island) and partly over the highlands of Scotland.

This distance doesn't seem very far, given the distances you guys
have to work with, but we're running fairly low TX powers - down to 1W
or less - with very low ERPs - we're limited by the license to 100mW
ERP.

My antenna is a vertical wire 11m high (held up by a fibreglass mast
from Spiderbeam) topped by 4 sloping capacity hat wires of approx 3.5m
length, tuned against a mess of radials with approx 500uH of inductance
on a home made variometer.

The lightning noise has been quite bad over here lately, as the
propagation lengthens at night the noise from storms over Europe comes
in, and crashes around at S8-9. Despite that Finbar and I have managed
a QSO 6 nights of the last 7 at 11pm local time.

I had a QSO last night with G3OLB in Devon - a distance of 654 miles -
and about as far as you can go in the UK.

Finbar runs (as far as I know) a top loaded vertical - with 4 long top
wires and a rather higher vertical section than me, held aloft by a
versatower, over a much more extensive set of radials and earth rods.
I'm not sure of the dimensions

He was receiving me on a 1m amplified loop antenna, or a 120m low lying
"mini-beverage" though - so his efficient TX antenna has no bearing on
his ability to receive my flea power signal!

The static crashes were much lower last night, only peaking around
S4-5, which greatly improved readability at the lower power levels.

I have tested a way of reducing my power in a controlled/calibrated way
down to 100mW or less today, so hope to try some real QRP tests
tonight, as long as the QRN stays at bay.

Looking forward to the autumn season when the thunderstorms die out and
conditions improve, then we might be in for some cross pond - cross
band QSOs? (By cross band I mean between our differing 500kHz
allocations - we have 501-504kHz, you have higher, around 505?)

Hope this helps, and feel free to email me direct if you want more info.

Cheers,

John
GM4SLV
Shetland Is.  IOTA EU-012