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Re: Re: LF: ZL DX testing 21 September (was 22 September)

To: [email protected]
Subject: Re: Re: LF: ZL DX testing 21 September (was 22 September)
From: "John Sexton" <[email protected]>
Date: Fri, 10 Aug 2001 07:42:57 -0700 (PDT)
Reply-to: [email protected]
Sender: <[email protected]>
Dear Jim, Bob, LF group,

This is very interesting. Most probably a result of the different antennas Jim 
and I are using.
We not infrequently listen to the Kaliningrad transmitter, since it is one of 
the few Russian broadcast stations that is received well in the UK. They are 3 
hours ahead of us and are currently on Summer time, hence their local midnight 
is 20.00 UTC. It is really only listenable after dark but then it is well 
received. The carrier is clearly present at all times and I can make out every 
second or third word in the middle of the day.

By the way I found out why the anthem played was the old Soviet one. Apparently 
Yeltsin wanted it changed, but no satisfactory replacement was found and when 
Putin (known locally as Rasputin) came to power, being a good old boy he 
ordered that they stick with the old anthem.

The transmitter is on all day long every day, at least until their midnight. 
The station I heard after their midnight on 171 kHz was definitely slavonic and 
could have been Moscow (which might stay on later), although interestingly 
there is indeed an Arabic station on this frequency, Nador, Morocco. 1.2kW and 
I guess this is what Jim is hearing. My loop points East/West and picks up the 
Eastern European stations in preference. I shall try the other loop tonight 
which is oriented North-South.

By the way 180kHz is allocated to Ankara, Turkey. 1.2MW.

I would confirm Mike's comments that if Europe 1 on 183kHz is not heard in ZL, 
then the chances are very slim. This is not a standard broadcast frequency by 
the way.

Regards, John, G4CNN

-----Original Message-----
From: "James Moritz"<[email protected]>
To: [email protected]
Date: Fri Aug 10 05:45:28 PDT 2001
Subject: Re: LF: ZL DX testing 21 September

Dear Bob, John, LF group,>
I heard the Russian station on 171kHz for the first time last night - it shut down at 2000 utc as John says, but was only audible from 1900 at my QTH, which might have been due to propagation, or then again, it may just have been on the air for an hour. I have not heard it before when monitoring this frequency, so it may have very limited operating times. After it had closed down, another station was audible on the same frequency, with what sounded like Arabic music playing, but this was considerably weaker than the Russian station. Looking at a spectrogram display at frequencies close to 172kHz, the effect of this QRM was not unlike the "Luxembourg effect" noises often heard at the top end of 136k. The net effect was to raise the noise floor by a few dB, although QRN was still the main source of noise.

Of course, one way to improve the situation would be to null out the offending noise with a loop - if the wanted signal from ZL comes over the pole, and the unwanted signals originate in Russia, this should work fairly well - does anyone know what bearing a signal from ZL should arrive on?

It seems strange the LF spectrum does not get used much "down under" - I would have thought it would work very well with all that ocean to propagate over.

DBF 39 transmits a carrier on 138.83kHz most of the time, interspersed at intervals of several seconds with short bursts of FSK data, mark 138.83kHz, space 139.17kHz. On a spectrogram, it will look like a 138.83kHz carrier unless a very coarse resolution is used.

Cheers, Jim  Moritz
73 de M0BMU





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