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
<[email protected]>
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