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QRM on 7.116MHz


Is anybody else hearing some form of data transmission on 7.116MHz?
Its quite wide making 7.114 to 7.118 unusable.
I realise that from 7.1 to 7.2 we are a secondary user so the source may not even be amateur. When working QRP from a summit it makes a QSO very difficult if not impossible.



In reply to GM4NFI:
Hi Dave. Nothing to report here in North West Wales. Sorry m8, good luck with your activation.


In reply to GM4NFI:

I get a digital signal centred on 7.118 every day, usually starting about 3pm ish. It builds until the frequency becomes unuseable. Presently the frequency is clear with s2 noise here.


In reply to G1INK:

Likewise here.
It was also heard throughout the summer from France.


In reply to M0LKB:
Yes, I have it from here too (Swindon).



In reply to M6HBS:

Its totally gone today (Sunday) perhaps its only there on weekdays. I intend to listen further and will update in a few days.

Thanks for the responses.



In reply to GM4NFI:

It was certainly there today (Sunday) when I checked from G/SP-015 Bosley Cloud. Pic of set-up here:- (making the most of the sunny weather)


In reply to GM4NFI:
I could hear it here mid afternoon today Dave. Military perhaps?



In reply to M6HBS:
9.00PM Sunday and its back worse than before. It makes 7.114 to 7.120 unusable with me and its S8 to S9 tonight far worse than previously.



In reply to M6HBS:
Monday 1PM and its gone. 7.116MHz is QRM free. Pity the WX is very poor and unsuitable for climbing hills!

Will keep monitoring.



In reply to GM4NFI:

Is this it?


In reply to G1INK:

That’s the blighter. Doesn’t sound like RADAR to me, but I’m happy to stand corrected on that. The clicking sent after the callsign and varying power carrier on the 5MHz beacons sounds more like RADAR.



In reply to MM0FMF:

Just had a listen & it’s S9 here in IO83SS at 2230z.

There appear to be two definite peaks at 7116.5 & 7117.5


Mark G0VOF


In reply to G0VOF:

At 2243z it sent some CW on the higher of the two frequencies 7117.5 KHz

I grabbed a snapshot of some of it but it doesn’t make much sense

skLt284495756t77t61t1362ttb 9 e46t83n e t8 1t1d e2= re a4ki

The above (captured using Hamscope) is correct & is what I heard with my ears. I did miss about 10 seconds at first before I started the capture.

Edited to add:

More CW at 2257z, maybe it does this every 15 minutes or so?



Mark G0VOF


The QRM stopped at about 2340z, I didn’t hear any more Morse apart from that already mentioned. Two passages around 40 seconds long at about 20wpm at 2243z & 2257z.


Mark G0VOF


In reply to G1INK:

Condrats Inky, you are able to decode digital signals and read ‘Vote P100’ …!!! :wink:

73 Alain F6ENO


In reply to F6ENO:

I left my recorder running while I had my tea & there was some more readable “Morse” sent at 1744z.

It looks like this is some form of RTTY with 1 KHz shift. The tone you hear most of the time is whatever is sending the RTTY just idling. I have slowed my recording down & the tone cycles between the upper & lower frequency at 25Hz.

The readable “Morse” sent at 1744z indicated that the callsign of the station sending the signal is REA4

I would hazard a guess at this being Russian Military or diplomatic traffic.

Anybody else any ideas?

Best 73,

Mark G0VOF


The above message was repeated at about 1920z with only one character changed.

This station is REA4 & has been been around in different places for donkey’s years (Google the callsign), & is most often listed as headquarters of the Russian Air Force.




In reply to G1INK:
Yes that’s it sometimes S9 with me makes the calling frequency unusable.



In reply to GM4NFI:

Yes that’s it sometimes S9 with me makes the calling frequency

At the moment it seems to be S9 slap bang on 7.118 MHz :frowning:

73 Rick M0LEP