40 years since hijacking of Southern Televison

Not TV, but similar theories surround the repeated hijacking earlier this year of Mansfield 103.2.

Guardian: Local radio station keeps getting hijacked by song about masturbation

I doubt the perpetrator was really able to overpower the 103.2 signal over such a large area as the article suggests. Most seem to think it was the radio link from the station to the transmitter that was hijacked.

Yes, some small community radio stations of this type use 45 MHz analogue STL links, which to be frank are rather too easy to hi jack

That's my local station, I'm suprised I'd never heard of this incident until now!

Is it possible for something like this to happen now a days? Espeicla with all those sky dishes?

Most links require another valid signal to be present, without it being there, the transmitter ignores the feed.
That stops an awful lot of pranks like the ones that affected TV distribution prior to the 1980s.

A small community radio station probably doesn't have the funding to put extra equipment in the signal path, and is therefore at risk of this hijacking.

It's not the existence of dishes that makes it more difficult (in fact in some respects it would theoretically be easier on satellite*) it's the fact that everything is digital. For a start broadcast channels are distributed and broadcast in multiplexes - several channels in one transport stream on one signal. Then there's the actual creation of the signal to override another one. You've not only got to create an MPEG stream but accompany it with all the relevant PIDS and other metadata that the receiver will accept. Not actually that difficult to produce if you have a very common but fairly expensive bit of kit.

However everything is moving over to IP, which on one hand creates another layer of complexity but also could actually make it easier.... it takes it from the realm of hobbyist electronics to computer hacking


*overriding signals on satellite is very easy and it happens fairly often, either accidentally** or maliciously***. Stations like the BBC and Al Jazeera get jammed by hostile governments and others every now and then. However that's just disruption, doing it with something that would replace the existing transmission is another matter, the two signals would fight and interfere with each other, upping the power to fight off each other would just add distortion until presumably the transponder would be overloaded and shut down.

**which does happen with 'adhoc' feeds, which is why they have to be talked up carefully

*** it is possible to triangulate to detect roughly where the source of the rogue uplink is, I've no idea how and I don't think it's that accurate

And also non malicious cases of transmitters rebroadcasting the wrong feed during lift periods, after their correct feed station had gone off the air for the night.

The Wrekin in Shropshire carried a German channel once, and the whole BBC 2 Scotland tx network from Angus northwards carried TVS from Rowridge !

I have heard that in the old days of regional BBC 1 continuity that David Stevens would keep BBC 1 Midlands open longer than the rest of the network and the RBS links would give him a far wider audience than was intended......

And on radio... http://wiki.tx.mb21.co.uk/index.php?title=The_Day_that_North_Hessary_Tor_Went_Commercial

I can't find any reference to it but I'm sure there was a case of someone 'hijacking' a BBC radio transmitter on the south coast somewhere and playing Paul McCartney's song 'Give Ireland Back To The Irish' over and over again

Radio 1/2 Rowridge was hacked a few weeks after the Southern TV incident at Hannington. Back then
Rowridge was RBL Wrotham, so they simply swamped out and replaced the feed signal from a location near the transmitter (exactly how the Hannington hi-jack had been done) . The perpetrators played some BBC banned records, and the transmission carried on all night. When the R2 network shut down for the night at 02:05hrs, Wenvoe detected the Rowridge transmission, and switched to RBS, so the whole of southern, SW, and western England was covered, along with south Wales (possibly further).

About the same time as that, someone had placed a fake job ad in Wireless World, pretending to be from the IBA advertising for the post of 'Head of Transmission Security'

That's the incident I was thinking of.

I have heard about a similar taking over of an RBS/L link happening with one of TSWs transmitters after closedown. I think it was the same incident that was reported as being an engineer at the station watching something they shouldn't