Hi Elliot,
I doubt you could have beaten the Sturba rotating curtain. The field path covered 40% of the globe when they were in operation. Can I hire one on holiday 
Night night - must go now as something on the radio - BBC⌠!
Mike
Itâs often not that wide. Itâs been wandering up and down the band for weeks now.
It makes me feel quite nostalgic when I hear it, throws me back to the 70âs when Woody was always around and you could work the world on a wet noodle and a single ECL80.
While we are on the subject of interference. From my understanding (talking about 40M now), broadcast stations agreed to stay out the 40M alocation 7.1 - > 7.2 by the WRC in 2003.
I have observed AM broadcast signals near the bottom end of the band, last night around 7.120 MHz, not huge in signal strength 57- 58. There is now a Portuguese station around 7 MHz, why on earth are people using these frequencies ?
I too have observed similar high power transmissions on 20M esp around ~14.2.
I am starting to wonder if anybody actually cares about HF allocation anymore, Does SOTA need a vigilante group of transmitter destroyers I wonder âŚ
Jonathan.
Log the time and frequency (and hopefully the station ident) and inform the Intruder Watch service
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When you follow up the IW actions on these transmissions it often turns out to be accidental harmonic or spurious transmissions which are then corrected. These signals can also come about as images and cross-modulation products in your receiver. Sometimes, though, you get unofficial stations run by rebels in disputes, and they are not going to listen to complaints!
Brian G8ADD
I read that there is one amateur activity which actually does drive OTHR off of the ham bands: contests.
Of course, that doesnât exactly solve the problem for a SOTA activator⌠
Very interesting breakdown of various OTHR and similar systems on that IARU site: http://www.iarums-r1.org/iarums/radar-2013.pdf
Actually, this is a good thread in which to mention another source of interference which I tracked down recently, particularly because I see it in the spectrum screenshot posted by G4ISJ. Notice the carrier at about 14.213 (should be audible on 14.212 USB). I would bet that similar carriers are present at about 14.029, 14.090, 14.151, 14.273, and 14.334âŚ
â73 Karl KA3RCS
Hello,
name here is Swa, ON5SWA,
chasing summits is new for meâŚsince january this year.
I noticed the same interference here on 20m. Same area. I already made several printouts from a websdr and also a recording. I sent it to the radiosociety here (UBA).
Signals are here way above S9 up to S9+40. Sometimes early in the morning, sometimes around noon.
I am hearing that signal since mid of august I believe. Today I did not hear it, Maybe its also suffering from the bad conditions on 20m (solar storm, K index 20).
73 and work them allâŚ
I was listening to the said AM station on hack green. Of course it is always possible that it has been aliased back into the pass band as you mention Brian, considering it was only S-7-8. Maybe they need some better front end filters ! OR they havenât obeyed Nyquist sampling.
Jonathan.
Hello Swa,
âToday I did not hear it, Maybe its also suffering from the bad conditions on 20m (solar storm, K index 20).â
Not sure which is worse, the QRM or flat band. On balance I would rather tolerate the QRM than a flat band. Here was what 20M looked like a few minutes ago, 40M not much better.
RX1 is on a hexbeam, the lower trace (RX2) is receiving signal via a SteppIR vertical. Not much difference between the two. Strangely the RF black hole for me appeared about 10.00Z. I have heard a lot of chasers this morning so perhaps the RF black hole is just over me right now 
If you click the image below it becomes full size.
Mike
Thats very clever 
Is it very silly of me to ask âwhy do they do this?â
Why âwhoâ does âwhatâ?
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Assuming that you mean the use of Over the Horizon Radar, it has many uses.
Long range aircraft detection
Detection of missile launches (esp. ICBMs)
Long range detection of shipping
Sea wave-height analysis
âŚand probably others.
The best systems work effectively at 3,000-5,000km.
They can be quite useful and interesting for radio amateurs. Many years ago I was involved in a project monitoring the oblique ionospheric sounders of this system in Australia.
Much instructive data can be gathered:
http://www.qsl.net/zl1bpu/IONO/chirps.htm
http://www.qsl.net/g3cwi/propagat.htm
You can try it yourself.
Very interesting, thank you.
Its not just Putin trying to start WW3 then?
Hello,
It is back at 59+30 âŚsobâŚa few minutes ago. Any other EU stations getting this?
It just went off at 1326Z 8)
Mike
Yes, lots of people will get it. Anyone in the skip of the sodding great OTH radar transmitter.
That nice Mr. Putin seems a reasonable chap, open to debate and negotiation, so why donât you write to him and ask him to QSY a little. Hereâs his address:
V. Putin Esq.
The Kremlin
c/o PO Box 88
Moscow
Russia
Donât forget to enclose 2x green stamps if you want him to reply.
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Hello Andy,
Sad and pointless I know but when it first popped up I did write to Mr. P - really just to see if there was any response - via:
http://eng.letters.kremlin.ru/
Zero return.
He doesnât need stamps he has plenty in the UK
Mike
PS: I cannot quite see his Dan markings on his belt but his kit is lacking creases so another pose I guess !!
Iâm sure if you challenge him to a little bit of rough and tumble youâll find out his Dan-ness soon enough.