GB2RS News Service Letter
Gordon L Adams G3LEQ
FIRSTLY DATA DEVELOPMENTS
At the turn of the year Steve G4HPE commenced a number of test DATA transmissions
on 5290kHz using MFSK16 (40wpm), MT63-1kHz (100wpm) and MT63-2kHz (200wpm).
Then, starting early in the Summer I was able to join in the tests using
the facilities of the North Cheshire Radio Club station GX0BAA.Assisted
by members David G0VIE and Alaster M1DFO we have been putting out similar
DATA tests around 1990kHz on Sunday evenings using the two MT63 modes
consecutively. The voice script is usually read at a speed of between
160 and 170wpm, and comparisons with the DATA transmissions have been
most interesting.
MFSK16 tended to be perhaps the more reliable in very poor propagation
conditions, but most of the time was considered to be too slow. MT63 is
recognised to be a very robust mode when interference is present on the
channel. With 2kHz bandwidth this has proved to be very impressive, but
errors tended to occur during severe fading. The narrower MT63 with 1kHz
bandwidth maintained accurate copy better during deep fades. When assessed
against the SSB voice readings MT63-1kHz compared very favourably - particularly
under poor propagation conditions. Up until the time of writing these
tests have been carried out on a point-to-point basis between several
participating stations.
However, provided that a few more volunteers can be found to assist with
the DATA transmissions, I hope to announce a regular Sunday evening GB2RS
DATA broadcast early in the New Year. This will employ MT63-1kHz USB with
long interleave at 21.00 hours local time between 1990 and 1993kHz and
also in parallel between 3590 and 3593kHz. At the moment final proving
tests are taking place on 1992kHz and 3592kHz, but the precise frequency
may change slightly according to the type of interference present at the
time of each transmission. Regular users of this mode will know that it
is easy to optimise receiver tuning just by looking at the "waterfall"
display on their computer. Reception reports may be sent by E-mail to
gx0baa@ntlworld.com or given using USB voice on 1992kHz around 21.20 to
21.25 hours. A further opportunity to discuss the DATA transmission will
occur at around 21.55 hours after the 21.30 hours LSB voice news reading
on 1990kHz ends.
If all goes well, the same MT63-1kHz DATA news bulletin may be introduced
using my own station G3LEQ at 20.30 hours local time on 5290kHz and 7090kHz.
However, with the present state of the sunspot cycle and the consequent
low F-layer critical frequencies, these transmissions will be heard mainly
in Europe and the Middle East. All the DATA transmissions together with
the LSB voice bulletin on 1990kHz consist of the National News followed
by the updated Propagation Report, which is prepared by G3USF and G0CAS
on the Saturday evening. Those interested in the accuracy of their reception
can therefore compare the text with that which appears on the RSGB and
Propagation Studies Committee web sites.
SECONDLY THE 7MHz EXPANSION
The second development during the year was the extension of the 7MHz
band for UK amateurs up to 7.2MHz on 31st October. Both Jimmy GI3GGY and
myself carried out tests on the first day, and 7150kHz was found to be
clear of broadcasting stations. A simulcast was also carried out comparing
the propagation of GB2RS on both 5405kHz and 7150kHz across the UK. Accordingly,
the 10.00 hours GB2RS News bulletin was moved permanently from 7048kHz
to 7150kHz starting on Sunday 7th November 2004. The current experimental
USB voice bulletin continues to go out at 12.30 hours local time on 5405kHz
(nominal) and is followed from time-to-time by an MT63 USB DATA test on
5290kHz (nominal) at 13.33 hours. This start time, three minutes after
the half-hour, allows reception of our three 5MHz beacons GB3RAL GB3WES
and GB3ORK to be checked out for comparison purposes.
THEN AND NOW
Next year the GB2RS News Service will celebrate its fiftieth anniversary.
It has always been transmitted on a Sunday, and may be likened to a weekly
newspaper. Back in 1955 it was radiated on 80-metres, although some tests
had been carried out previously on 40-metres. Currently, it is read every
Sunday morning and evening by a team of about 125 readers (including standby
operators) on nine different amateur bands - namely 1.9 3.6 5.4 7.0 50
70 144/145 433 and 1300MHz, the latter being a networked ATV transmission
on the South Coast. Because of the current low state of the sunspot cycle
the 7MHz band usually presents skip propagation into Europe, but the last
reading of the day on 1990kHz provides excellent UK coverage.
Jeremy Boot G4NJH continues to put out an RSGB-approved voice news reading
on the Internet which includes MP3 Real Audio. This is employed in various
Countries in order to enhance their own news services. An example of this
usage may be heard emanating from Tasmania via the URL liveaudio.irlp.net:8004
A selection of news sources including GB2RS can also be viewed on the
Tasmanian "Spectrum" news home page www.vk7ax.tassie.net.au/spectrum/
RESEARCH FOR THE 50th ANNIVERSARY
I am currently in the process of gathering together material for a two
or three page feature in RadCom, which it is hoped will appear around
next August/September in celebration of the GB2RS 50th Anniversary. If
any of you have some GB2RS related recollections, photographs or memorabilia
that might make interesting reading - then please forward them to me by
post or by E-mail at gb2rs@ntlworld.com If you prefer to send a FAX -
then my facsimile machine is still operational on 01 565 634 560. Thanks
to the diligence of John Crabbe G3WFM our Honorary Historian and librarian,
I have already an interesting selection of RSGB Bulletin extracts and
Council Minutes. These concern negotiations that took place with the Post
Office during 1954/1955, prior to the first GB2RS News broadcasts in September
1955.
THE PRESENT DAY
Currently, the GB2RS news script is posted to about 35% of our newsreaders,
whilst the majority now receive it by direct E-mail or download it from
the RSGB web site. The latter version is presented for viewing rather
than reading out aloud, and contains a number of iconic illustrations.
A rally survey of potential listeners has been carried out during the
year. This revealed that about 65% of rally attendees make use of GB2RS
News in one of its guises. Of those who hear it on the air - around 60%
listen on 145MHz. Most of the balance take it on 3.6MHz or 433MHz, the
latter being delivered via repeaters. Only 10% of listeners make use of
the evening broadcasts. It would therefore appear that GB2RS is still
a much-valued facility; which is provided by the RSGB's volunteer team
of newsreaders, and is intended for all radio amateurs, short wave listeners
and Internet surfers. I take this opportunity of thanking all of our GB2RS
newsreaders and the editorial production team at RSGB HQ for their hard
work in maintaining the service, and wish you all a very happy Christmas.
I trust that we shall gain great satisfaction from the celebration of
50 years of the GB2RS News Service next year.
Gordon L Adams G3LEQ - GB2RS News Manager and
Board Member. 7th December 2004.
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