Jammer on 7040

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Dec 21, 2008
louisville ky
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Mystery Carrier!

Was it cover up of a government conspiracy? Perhaps it had something to do with terrorists, maybe a super secret government experiment - or maybe UFOs and space aliens.

Personally, I'd like to think it was somehow related to the UFO/alien thing. In some ways, even after watching several versions of "War of the Worlds," that's a more comforting thought than terrorists. But I guess we'll never know because the Federal Communications Commission just ain't saying what it was.

I'm talking about that obnoxious and mysterious carrier that appeared from time to time on 7.040 KHz - usually just when someone (mostly QRP stations) wanted to use the frequency for calling CQ. The carrier was heard at various times this past summer and fall by me, WY3H; John, K3WWP; Mike, N2COD and others. When it appeared it would drone on for an hour or more, sometimes several hours without ceasing.

After discussing the matter with John I decided to make a personal call to the ARRL's Field and Regulatory correspondent, Chuck Skolaut. Chuck promised to check on the matter as soon as he was free from dealing with another matter. When I didn't hear from him after a few days, I called him again. He then said he was waiting to hear from the FCC. About a week later I got the following e-mail reply from Chuck:

After inquiring about it last week, the FCC monitoring station issued this report;

Following up on your complaint of a carrier on 7040 kHz, the FCC's High Frequency Direction Finding Center and Enforcement Bureau were able to locate the source of the emission and get it off the air. We have not observed the signal on the air since October 27th. Please let us know if you continue to receive reports pertaining to this signal.

When I asked for details, I received this, sorry.

Unfortunately I can't release any details other than what I previously mentioned

Chuck Skolaut, K0BOG
Field & Regulatory Correspondent
ARRL, The national association for Amateur Radio

E2K10 - Oddities

An enquiry has been received via email concerning jammers that apparently operate circa 1630z and very strong in Athens, Greece. The freqs mentioned were: 5320, 5600, 6420, 6880, 7040, 7050, 7070, 8320, 8340, 8515, 9360,10280,10470 and 13410 kHz.

The answer that we received via 'C' makes interesting reading:

"Most of what is mentioned is emanating from Iran, these same jammers were used against E3 (Lincolnshire Poacher) for many years, initially between 1000 and 1445z and 1800 to 2245z, with increased anti-Iranian clandestines coming on air the jamming was cut back to end at 1445 and resume at 2000z (rather than 1800) when more transmitters became available. Some time ago this all stopped, with improved (if only temporary) relations between Britain and Iran.(Wait for next war).

Iran seems determined to block anything it does not want the population to hear, some years ago (mid 90s) it purchased from the West a large number of Telefunken transmitters which were set up at Sarjan (phonetic) in central Iran, there sole purpose was not for broadcast use but to jam incoming transmissions, in times of crisis (e.g. recent elections) they were turned against BBC VOC and KOL Israel's,Persian services - although this is not the norm.

The most hated station is Voice of Mojahed National Liberation Army of Iran. This broadcasts from Iraq (I must confess that I am not sure if this is controlled by the regime or from Northern Territories). Some of these stations have been linked to MI6 and the CIA who fund them through shell operations, Of late there was talk of Radio Free Iran, a CIA station - with the ever changing scene in that area I am not sure what is happening. I did read that a transmitter had been commissioned (Collins I think) and was to be sent to a 'secret' location very soon, in order to commence transmissions. Some transmissions are sent on MW from Kuwait also.

VOM continues to grow and this is putting more pressure on the Iranian jamming network. Two VOM services operate.

VOM 1: 0225-0635 1125-1235 and 1425-1835z * all approx. varying on 5350 5625 5665 6450 6480 7050 8315 8365 8520 8815 8865 9335 10250 10450 and 13450kHz, these jump freq. every few minutes to avoid jamming. In the UK audio is often better heard above 9MHz in the afternoon period, jammers seem quite strong most of the time.

VOM 2 : is heard 1700 to 2100z on approx. 7075 kHz and tends to stay put most of the time. This is jammed by two jammers. They hate it twice as much. A warble jammer and a transmitter sending a steady carrier, 50 Hz offset gives it a very nasty low pitch 'wine'. Just now and again the second jammer is not used, when only the warble is in use it is possible to hear the programmes, I guess 7075 is a more powerful transmitter - possibly closer to us in the UK.

It is not beyond reason to suggest these stations are engaged in intelligence related matters.

To add to the problems there is nothing short of a multitude of varying smaller clandestine - without expert (BBCMS) information it is hard for the casual listener to work out who what and where they are broadcasting to/from. Iranian jammers will seek and destroy anything they even suspect might be broadcasting against them - they have an efficient monitoring service and are not in the ITU - so don't care... Also to make matters even worse they are now using SW frequencies to send jamming signals between remote transmitters, rather like 'jamming feeds' - suggesting that more sites are in use.

China is the second largest jammer. They however, use a domestic service transmission offset on a broadcast channel (usually Radio Free Asia) to block out the audio, making it into mush, they do this so they can claim -they do not jam - it is the other station causing interference - strange Chinese logic.

Lets face it though, it did not work for the USSR and they spent millions on it for 50 years...."

©'C' [Thanks C]

ARRLWeb: Who's Jamming Whom? Getting the Story Straight on the 40-Meter Jammers
ARRLWeb: "Mother of all Jamming Stations" Continues to Plague 40 Meters

This signal is still on 7040 off and on through out the day.
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