Video puzzle - 72.5 MHz

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daveB
Posts: 1628
Joined: 07 Oct 2014 16:49

Video puzzle - 72.5 MHz

Post by daveB »

This is a nice puzzle, maybe someone with image manipulation software can straighten up the attached image.

At 11:15-11:16 on 11 July 2020 at the end of an Es opening to BLR/UKR I spotted what looked like a video signal on the I/Q recording. The attached image is what appeared on the TV plug-in on SDR Sharp.
11Jul2020_72500kHz_unknown video.jpg
It is definitely a video signal, but judging by the slope it is not the standard 625 line/50Hz analogue signal. It looks like it could be a testcard, but it needs to be manipulated to square it up. 72.50 MHz is not listed as a TV broadcast channel.

It is actually 72.503 MHz to the nearest kHz.

It is intriguing - has anyone any ideas?
Location: Sittingbourne, Kent JO01ji
SDRPlay, AirSpyMini, RTL dongles, ST311, Yamaha TX930. 5 ele yagi 20ft agl - 70 deg. FM5 - 80 deg, 5.1 Yagi 16ft agl - 120 degFM5 -180 deg. Vert 3-ele Moxon - 80 deg. Shielded magnetic loop 0.1-200 MHz - 10 ft agl

daveB
Posts: 1628
Joined: 07 Oct 2014 16:49

Re: Video puzzle - 72.5 MHz

Post by daveB »

Here it is rotated and stretched - you can see some images - but what?
11Jul2020_72500_video-manipulated.jpg
Location: Sittingbourne, Kent JO01ji
SDRPlay, AirSpyMini, RTL dongles, ST311, Yamaha TX930. 5 ele yagi 20ft agl - 70 deg. FM5 - 80 deg, 5.1 Yagi 16ft agl - 120 degFM5 -180 deg. Vert 3-ele Moxon - 80 deg. Shielded magnetic loop 0.1-200 MHz - 10 ft agl

pe1etr
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Joined: 07 Oct 2014 00:40
Location: Near Lobatse, Botswana

Re: Video puzzle - 72.5 MHz

Post by pe1etr »

daveB wrote:
12 Jul 2020 16:03
Here it is rotated and stretched - you can see some images - but what?

11Jul2020_72500_video-manipulated.jpg
Is one of your neighbours forging foreign banknotes?

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Chris Howles
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Joined: 06 Oct 2014 18:54
Location: Lichfield, Staffordshire UK.

Re: Video puzzle - 72.5 MHz

Post by Chris Howles »

I had an unid R3 on 77.250 back in May too. One possibility is Lugansk Ukraine which is mentioned in the May edition (244) of Teleradio News as being on 77.250.
Denon TU-1500RD X4, Rotel RT-955, Icom IC-R7100, Tescun PL390, Auna DAB, D100 TVDX conv
Homebrew 6 el modified Triax FM, Homebrew 3 el OIRT, vertical FM 3 el, FM dipoles facing SW and SSE, 3 el DAB
RDS Spy

daveB
Posts: 1628
Joined: 07 Oct 2014 16:49

Re: Video puzzle - 72.5 MHz

Post by daveB »

Is one of your neighbours forging foreign banknotes?
Hi Peter - It does look a bit like that doesn't it.

Hi Chris - not 77.5, but 72.50 MHz

David
Location: Sittingbourne, Kent JO01ji
SDRPlay, AirSpyMini, RTL dongles, ST311, Yamaha TX930. 5 ele yagi 20ft agl - 70 deg. FM5 - 80 deg, 5.1 Yagi 16ft agl - 120 degFM5 -180 deg. Vert 3-ele Moxon - 80 deg. Shielded magnetic loop 0.1-200 MHz - 10 ft agl

bigic
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Joined: 13 Nov 2019 00:19
Location: Bela Palanka, Serbia

Re: Video puzzle - 72.5 MHz

Post by bigic »

Did you record an IQ file? And was an audio carrier present nearby?

Tim Bucknall
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Joined: 01 Oct 2014 14:55
Location: Now stranded in Congleton
Contact:

Re: Video puzzle - 72.5 MHz

Post by Tim Bucknall »

Can you upload the original IQ file please?
Also can you invert that image to negative just to see if it’s any more helpful?

Mixing product being created at a tx site or a leaking cable system?

What tx sites were heard at the time?
Rx: Burkhardt Reuter RDR54D1, Elad FDM-S2, Airspy HF+ w/ HS Publications 6 Element R3 -R5 Yagi on rooftop rotator V/H polarization options. Pira P275 RDS analyser

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Chris Howles
Posts: 515
Joined: 06 Oct 2014 18:54
Location: Lichfield, Staffordshire UK.

Re: Video puzzle - 72.5 MHz

Post by Chris Howles »

daveB wrote:
12 Jul 2020 21:52
Is one of your neighbours forging foreign banknotes?
Hi Peter - It does look a bit like that doesn't it.

Hi Chris - not 77.5, but 72.50 MHz

David
Oops my bad, eyes not as good as they used to be!
Denon TU-1500RD X4, Rotel RT-955, Icom IC-R7100, Tescun PL390, Auna DAB, D100 TVDX conv
Homebrew 6 el modified Triax FM, Homebrew 3 el OIRT, vertical FM 3 el, FM dipoles facing SW and SSE, 3 el DAB
RDS Spy

Tim Bucknall
Posts: 3305
Joined: 01 Oct 2014 14:55
Location: Now stranded in Congleton
Contact:

Re: Video puzzle - 72.5 MHz

Post by Tim Bucknall »

Garry Smith says its a CRT in your vicinity
He gets this himself
Rx: Burkhardt Reuter RDR54D1, Elad FDM-S2, Airspy HF+ w/ HS Publications 6 Element R3 -R5 Yagi on rooftop rotator V/H polarization options. Pira P275 RDS analyser

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