Envelope-to: dave@picks.force9.co.uk
Delivery-date: Sat, 11 Feb 2006 14:18:57 +0000
From: "Mike Dennison" <mike.dennison@ntlworld.com>
To: rsgb_lf_group@blacksheep.org
Date: Sat, 11 Feb 2006 14:13:59 -0000
MIME-Version: 1.0
Message-ID: <43EDF127.10522.176AA48@localhost>
In-reply-to: <200602100734.k1A7Y498004958@post.webmailer.de>
Content-description: Mail message body
Subject: LF: Faster DX speeds?
Content-type: text/plain; charset=US-ASCII; format=flowed
Content-transfer-encoding: 8bit
Sender: owner-rsgb_lf_group@blacksheep.org
Precedence: bulk
Reply-To: rsgb_lf_group@blacksheep.org

> Copied Joe's 5wpm CW-signal here about 04:35-04:45 by ear. There was a
> lot of QSB. Signal peaking about 10-15dB above the noise.
> Hartmut

Congratulations, Hartmut and Joe, on this achievement.

What was the QSB like? Period between peaks and troughs? Depth? 
Regular or random? This information may help explain the propagation 
mechanism, and may also provide a clue as to how to make a QSO in CW 
(or other relatively rapid mode). For instance, large but brief peaks 
may point to trying modified meteor-scatter techniques. Longer, 
shallower peaks may suggest QRSS3 or even QRSS1 is most suitable.

The main problem with real DX propagation is the trade-off between 
speed and signal/noise, versus the length of time the propagation 
exists. The present beacons with dot periods of around 60 seconds are 
helpful but most practical two-way QSOs need faster information rates 
as the path is often not open long enough.

Also, I must have missed the detail of the recent VO1NA / M0BMU / 
G3YXM QSO, but can someone say what the speed/mode was and whether 
special procedures were used to keep the information transfer (and 
hence transmission time) to a bare minimum?

Is there any support for tests at faster data rates (NA to EU as well 
as EU to NA)? Would this upset the ongoing gathering of propagation 
data? I feel that until we learn how to exploit shorter, bigger peaks 
in propagation, we shall continue beaconing when 2-way QSOs could be 
possible.

Another barrier to potential two-way contacts is that Europeans are 
asleep for most of the time that the path is open. Does anyone have a 
solution to this? Again, learning to exploit shorter openings might 
allow QSOs to start at, say, 2300 or 0500UTC, which are less arduous 
than staying up all night.

Obviously, the main difficulty is that contacts are currently only 
possible with VO1NA, but perhaps now is the time to gain the 
knowledge that will lead to relatively frequent QSOs when eventually 
the US gets 136kHz.

73 de Mike, G3XDV
===============