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In UK they do things a bit different than we do here in America, and that includes broadcasting. A friend of mine did some work across the pond and found himself in Rowridge, it's a main transmission site for the south of England. In England they tend to group transmitters together in one room, one for each digital multiplex, each multiplex typically contains between 6 and 10 TV program streams.

This is quite different from what we do here in the States, even at Sutro Tower where there are 11 television stations each has it's own room and while some share a common antenna others have their own independent broadcast antenna. Back to Rowridge -

Rowridge is a transmission facility with 12 transmitters, six are on the air and each one has a complete backup transmitter and exciter. Each transmitter is a Paragon, made by Thomson Broadcast, these are high efficiency transmitters that use MSDC IOTs from L3. Paragon's use oil to cool the IOT, which is much safer than Glycol and does not require filters or constance monitoring. I had my own pair of Paragons at one station, and I liked them.

They broadcast in DVB-T (Digital Video Broadcasting — Terrestrial) and because each one is designed to run independently each has it's own DVB-T exciter.

In fact each transmitter also has it's own heat exchanger and if power is lost each cabinet has it's own UPS until the generator starts up .

The RF plumbing for this installation is quite complex as they must combine the six main transmitter outputs together and have RF switching to swing the transmitters outputs to the main or auxiliary antennas or switch up the standby transmitters as needed. So there are two combiners and 3 broadcast antennas at this site.

As you can see from these pictures the installation is very clean and orderly. Thomson Broadcast customized these transmitters and control systems for Rowridge.

The standby transmitters are kept in a Black Heat mode where the IOT is kept warm and can be turned on very quickly without having to wait for it to warm up. If a fault is detected in a transmitter that cannot be reset it's completely independent backup is switched on line in less than 30 seconds.

This is all part of the digital upgrade going on in the UK; which includes Wales, Scotland, Northern Ireland and England, . The government has staggered the rollout of digital television across the country so that they turn off analog broadcasting an area at a time and not all at once as we did. The network is owned and operated by Arqiva.