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40m heavy QRM 7030.0-7033.5 kc


#1

The whole weekend I experience big commercial QRM in the SOTA window, more exactly from 7030.0 to 7033.5 kc or so. So it’s hard to copy the SOTA activators. Would be good to move out of the window, surely it’s not local because I had it at my parents home (36 km away) and at my home the same.

73 & gl,

Axel, DL6KVA


#2

In reply to DL6KVA:
I have the same experience here in Edinburgh. It sounds like it could be a harmonic from a digital; DAB(?)- signal.
Anyone else have any clue as to where this noise comes from?
73 de Ken


#3

In reply to DL6KVA:

This multi-tone transmission appears on 7032 every month or so and lasts for about 3-4 days.

At my QTH on the North Sea coast it is about 559 during daylight hours, but rises to 599+ from around 1700 to 0800. Most SOTA activations using 7032 are unreadable under this noise. Fortunately most activators have migrated up to 10118 KHz, with considerable success.

It was last here from 8th-12th June and commenced this time on the 24th.

73
Roy G4SSH


#4

In reply to G4SSH:
A few of the guys here in Friedrichshafen have reported similar problems.

Andy
DL/MM0FMF/p
(excuse typos, sat in Lindau drinking beer)


#5

In reply to DL6KVA:
I felt ashamed giving lots of 479 reports for many of the activators during the passed few days as I have the same observation in JN97PM, East part of (Buda-)Pest as the jamming wide band digital signal often peaks S7-S8! Now I feel a bit better, hearing it was not a local problem…
Yesterday I turned off the circuit brakers of my house and fed my RIG from a battery in order to check, whether the noise origins from one of my house-hold appliances, e.g. computer or not? Unfortunately absolutely no change noticed… :frowning:
A VHF fan friend living in East Hungary told me that a few days ago he often has real S9, often S9+++ FM interference at 144.300, and other “channels” from direction Ukraine sending short, characteristically few words commands… (Please note, that the 2m band is EXCLUSIVE HAM band in the IARU Region-1 !!!) Maybe Ukraine confiscated not only the UHF / microwave bands above 432 and the upper 100 kHz of the 20m (also EXCLUSIVE) HAM band plus the entire 30m HF band, but others as well? (See: http://www.nzart.org.nz/h-quarter/infoline/2011-infolines-222-to-244/228-17-apr-2011/ )
BTW I noticed similar jamming signal at around 7.134 as well…

73: Jóska, HA5CW / M0HAA


#6

In reply to DL6KVA:
Thank You for the information. I heard big noise S7 - S9 on the summit today. I thought that my rig is out of order and wanted repair it Hi. Thank to all chasers for QSO in this QRM.
Jirka OK1DDQ


#7

In reply to DL6KVA:
turning on my radio I thought I´l go down some KHz because of the qrm with S7
but my alert was in the middle of the noice.
Next time I´l start at 7.026 so look there as well.

73,de arno oe9amj


#8

In reply to DL6KVA:The same here in Sweden during my activations and as chaser on the camping-place. nice to here that this QRM is not localy and homemade. So later, i will activate more summits from sweden during next week.
73 de SM4/HB9CMI/p now in Orsa


#9

The same is here. Level is 9+10dB by S-meter. I’m expect, that is some military purpose transmittion.


#10

In reply to HA5CW:

==
Maybe Ukraine confiscated not only the UHF / microwave bands above 432 and the upper 100 kHz of the 20m (also EXCLUSIVE) HAM band plus the entire 30m HF band, but others as well?

Situation is about the next: Military communication have their own band plan, independent of HAM band plans and IARU as well. We just can ASK them do not transmit on ‘our’ (HAM) frequencies. But it seems, they anyway think, they have all rights to any frequency from 0 to infinity, if they need ones.


#11

In reply to UT4FJ:

Military communication have their own band plan, independent of HAM band plans >and IARU as well.

Indeed they may have their own plans but the Ukraine government are signatries to international agreements. One of these is that the band 7.000 - 7.200 MHz is a PRIMARY amateur allocation assigned by the ITU. I’m not sure on the current state of democracy in the Ukraine but somebody needs to tell the Ukraine military to wind their necks back in and get out of OUR band. Or at least keep their QRM within Ukraine’s borders. Of course contstraining the QRM to within the Ukraine does not help Ukraine hams, so they need to take this up with their government.

Of course it is only suggested the QRM is of Ukrainian origin. If it turns out to come from somewhere other than the Ukraine, then the Ukrainian military can continue to wind its neck in and out as it pleases! :wink:

Andy
MM0FMF


#12

In reply to MM0FMF:

Actually, I do not know exactly, if there are military QRM, but this behavior is typical for these forces.

===
Indeed they may have their own plans but the Ukraine government are signatries to international agreements.

If you can hear some one letter CW beacons like C, D etc. around 7040, they are also military beacons which stay there for years, are still active, and were set up in former USSR, as I recall. And they located in former USSR borders, not only in Ukraine. So, it is not too easy to clear HAM bands from ‘special’ signals.


#13

In reply to G4SSH: Hello Roy,
I have no idea where it originates from but right now over on the West Coast of Wales its 59++, not a chance to hear anything underneath…

Steve…MW0BBU.


#14

7032.0 - 12 x 120 Bd BPSK + 1 pilottone, System AT3004D, QTH: Smolensk, Russia


#15

I’m sure we can’t really do something about the QRM lasting 4-5 kc at some time and strong over all Europe.

So once again better than fighting the QRM every day (like now with DC7CCC/p even on 7034) let’s think about moving the 40m CW center QRG. It can become 7027 kc for example, higher is all disturbed now here.

73 & gl

Axel, DL6KVA


#16

Gone :slight_smile:


#17

In reply to DF6PW:

Probably moved elsewhere.

Anyway 7032 KHz is clear for SOTA as from this morning.

Roy G4SSH


#18

In reply to G4SSH:
Has to be what is 59+++ on 7140 now!


#19

In reply to EI2CL:
Yes, the signal on 7140-7143 sounds like as if it is from the same source.
73 de Ken


#20

Hi all…
I have asked the IARU-Monitoring guys about the signal on 7.140…
I got a real quick answer.
The mode is 12 x 120bd BPSK system AT3004D
a russian ship near Gdansk.
Thanks to DJ9KR and DK2OM for the quick replay and their work…
hopefully the qrm will gone…

best 73 de Tom
DL1DVE