Transatlantic tests et al

[Andre' Kesteloot]

Peter Dodd G3LDO wrote:

> This report was delayed until the AMRAD report had been published on
> the website. This should be read in conjunction with the AMRAD report
> It was further delayed because of pressure of other work and for this
> I apologize
>
> TRANSATLANTIC TESTS. TRANSMISSIONS FROM THE UK.
>
> For the duration of the listening tests at Nags head I agreed with
> Andre', via e-mail, to co-ordinate some slow CW transmissions.
> To this end I had a meeting with the Crawley group and spent a very
> pleasant afternoon with Derek G3GRO and Lech, G3KAU. Dave, G0MRF (who
> designed the first of the LF solid state PAs) was also there. Apart
> from the main business we had a look at Lech's kilowatt solid state
> PA and loading coil system. We also checked out the Spectran software
> that the AMRAD group proposed to use to monitor a small segment of the band.
> We studied a recording of signal strength measurement of France-Inter
> on 162 kHz posted on <amrad.org>  web site and decided to focus our
> efforts between 0200Z to 0700Z.
>
> G3GRO, G3KAU agreed to transmit from the Crawley Radio Club with the
> larger antenna and Lech's PA with the power down to around 700W to
> stay within the 1Werp limit. Transmission times 0400 to 0600 decided
> on as the period of probable best propagation according to the signal
> strength measurements mentioned above. In the event the Crawley Radio
> club was not able to operate on the first night because the antenna
> downlead had to be replace (requiring the use of a double extension ladder).
> The other stations included in the test were Dave, G3YXM and Graham, G3XTZ.
>
> The factors influencing the choice of stations for the test were
> reasonably high erp, QRSS capability and frequency setting and
> stability. I also had to be able to communicate any change of
> operating time of frequency rapidly in the event of any feedback from
> Nags Head. The eventual line up was
>
> G3XTZ  137.780kHz
> G3YXM  137.770kHz
> G3LDO  137.760kHz
> G3KAU  137.750kHz (not transmitting first night of tests)
>
> The purpose of this 10Hz spacing was to place them in a narrow
> segment that could be examined in a narrow bandwidth with Spectran.
>
> On the first night received the first e-mail from Nags Head saying
> > We set up last night, Friday 15 Jan 2000.  Results follow.
> > Low noise, excellent conditions
>
> Transatlantic band conditions were very good with CFH 20dB over S9 on
> the TS850. Sharp crisp 'buckshot' QRN also an indication of good conditions.
> The weather was good, light wind, cold with light rain/sleet. no
> problems for transmitting.
>
> The first night was regarded as a test of the equipment as much as
> anything else. My exciter unit (crystal mixer) did not stay within
> the 2Hz limit I imposed. The problem was the temperature variation in
> the remote LF shack which ranged from  10 to -4 degrees C. The fix
> was to place the exciter on top of the R4C Drake receiver. All those
> valves (tubes) made a nice crystal oven and the frequency stayed within 0.5Hz.
>
> The main test was on Saturday/Sunday. All stations including G3KAU
> transmitted.
> G3YXM and G3XTZ transmitted from midnight UTC
> The weather was good, no wind, very cold. no problems for transmitting.
>
> E-mail from Nags Head reported no signals seen.
>
> The third night was a repeat of the second. The only incident was my
> keying relay stuck and the carrier remained on for at least the last
> hour of the test. Amazingly no melt down occurred - these FETs must
> be really well run in.
>
> E-mail from Nags Head reported no signals seen.
>
> >From the experience gained in co-ordinating this transmitting effort
> it should be possible to extend it through Europe for further tests.
>
> Andre' said
>
> > What was really great was to have all your transmitter frequencies
> > clustered in a fairly narrow band, as it allowed us to focus our
> > efforts with the dsp programs. Had your signals been all over the
> > band, it would have been much more difficult to jump all over the
> > place.
> > Once again, may we ask you Peter to convey our sincere thanks to the
> > rest of the British amateurs who participated in this event?
>
> Other news
> On 20/1 I worked OG5UFO operated by Reino He copied me 559 and I
> copied him 459 due to the Loran.
> I am always impressed by Reino's good ears.
> Tonight listened to a QSO between OZ5N and OZ1KML tonight 25/1 at
> 2045 and was able to copy everything over 15 mins of the QSO. I
> couldn't make anything of what I had written down - all double Danish to me!
> I haven't been able to work OZ as yet.
>
> --
> Regards, Peter, G3LDO
>
> <g3ldo@zetnet.co.uk>