The wide-band multi-tone transmission which has caused infrequent disruption to SOTA activations on 7032 KHz appears to have settled on 7032 KHz as from yesterday, 28th Feb 2011.
It is 559 at my QTH, from 7030 to 7033 KHz. and totally swamping any SOTA activations in this band. Petr OK1EQ is currently operating just at the lower edge, on 7.029.5 KHz.
Activators are using 7027-7030 KHz to avoid this QRM.
Looking at it with Spectran shows lots of carrier groups. It’s wider than the SSB filter in my TS570 but there are 12, possibly 14 or maybe 16 carriers being modulated.
The wide-band multi-tone transmission which has caused infrequent disruption to SOTA activations on 7032 KHz appears to have returned as from 0600 UTC this morning.
It is 539 at my QTH, from 7030 to 7033 KHz, rising to 599 during darkness hours.
If it follows previous patterns it will remain here for about 4 days before moving.
Activators are using 7027-7030 KHz to avoid this QRM.
In reply to G4SSH:
I have just worked with F/HB9AFI Kurt @7.032 from F/AB-382 and I was compelled to give him 479 report as even if he produced nice strong signal in JN97PM, I could understand only about half of his message due to the multiple tone wide band jamming signal, even if I narrowed the bandwidth of my receiver to the minimum.
The jamming signal we suffer from seems to originate from multiple sources. The reason of my thinking it is as follows:
For the time being there is a single jammed band section peaking at about 7.033 but the day before yesterday tuning up in order to check 7.118 I found another signal some 20-25 kHz higher. Now I can not detect it. That is, those seem to be independent from one another.
It’s good news that today we have only one jamming signal, but it’s bad news that it covers the band section mainly used for weak signal communication like QRP and SOTA activations.
Recently IARU associations used to have band monitoring services reporting for local telecommunications authorities the non-amateur operations within the dedicated, exclusive HAM bands. I hope that these are still active and take due measures in order to clear our bands from intruders.
Q: Is Russia member of the ITU?
A: Yes, it is!
Q: Are there radio amateurs in Russia?
A: Yes, there are plenty of them!
Q: Do they have a national amateur society?
A: Yes, they have!
Q: Are they IARU member?
A: Yes, they are!
Q: Did they notice the intruder?
A: Surely they also did!
Q: If this is the case, why don’t they submit immediately a very determined protest at the local competent authority as the most competent in the HAM community?
A: …
The same applies for Ukraine, Kyrgyzstan, Indonesia, Sudan, Kuwait, etc. even is in a fairly minor extent as about 3/4 of the “official” intruders come from Russia…
Unfortunately, against the flood of CBers nothing else can help but a massive and permanent amateur traffic disabling their communication.
In reply to G4SSH:
Being inspired by others I also monitored it on the band scope of a Slovenian SDR and found that the jamming signal covers the band section of 7025…7068 kHz …
Probably this is the reason, why most of the activators insist on using the good old 7031…7033 kHz section…