Assume somebody has gained entry to the transmitter shelter. what could they do if they wanted to put in their own feed? What type of interface would they be likely to find?
I remember an incident from the 80's where an Anorak in Dublin used a handheld self-built dipole and a small FM Transmitter to broadcast "The Ghost of Nova" on Q102. Radio Nova had been the biggest of the Super Pirates in Ireland and had closed due to shady dealings by the owner Chris Carey. It is still fondly remembered in Ireland to this day.
Anyway the Anorak rode his bicycle up into the Dublin Mountains and using his transmitter broadcast a signal at the relay. His signal was stronger because he was only feet from the receiver. This overrode Q's programing, and listeners got to hear Jingles and audio clips, from the glory days of Radio Nova. This only ceased when the Q102 engineer turned up after half an hour, and chased the Anorak all over the Dublin Mountains. The first link below is a discussion from 2008 about this incident see near the bottom of the page "infoanon 15th June 2008, 20:55" for the start of the discussion. www.radiowavesforum.com/rw/archive/index.php/t-15784.html
From the little I know of the legal stations here in Ireland they now use ISDN lines to link to the transmitter sites. So I suppose removing the ISDN line and replacing it with a cable of your own linked to a Laptop should be possible.
Hopefully other contributors will have better information and guidance on this subject. A note of caution though. Gaining entry to a transmitter site will most likely lead to a charge of Breaking and Entering/Burglary or whatever it's called where ever you live, if you are caught. This is on top of the charges for illegal broadcasting etc. If it's a hack against another Pirate say in London for instance, it has been known for the owner and some of his crew to turn up and give the intruder a good kicking. In one incident a few years ago the intruder was held over the edge of the top of the block of flats (apartments) where the transmitter was located. They did not throw him off the flats in the end, but I'd say he was a different s person after that fright.
"Lets see' we're on err 92 FM tonight, and it feels like a nice clean little band so far. No one else is using it. The price is right."
Mark Hunter - Pump Up The Volume.
