alt Hacker NewsAlso bear in mind that Droitwitch is radiating 3 different services. Talk Sport (1053 kHz), Radio 4 (198 kHz) and Radio Five Live (693 kHz).
My suspicion is that this means an exciter and a stack of amps per service, which then go through a two stage combiner and out to the antenna. There might even be a pair of exciters and amps per service depending on redundancy.
The combiners (certainly for FM/DAB/TV services) also cause cumulative attenuation as the signal gets combined each time, so even if all 3 are radiating at the same power, the first in the chain might need twice as much amplification to make up for losses.
edit: MB21 (of course) has some fantastic technical info about Droitwitch: https://tx.mb21.co.uk/gallery/gallerypage.php?txid=1454&page... and there's some great pics here, too: https://www.radiorewind.co.uk/radio1/droitwich.htm
I believe they're still using a pair of Marconi B6042 transmitters (250kW each, in parallel) to provide at least one of the services.
As far as I know the medium wave services aren’t transmitted from the same antenna as Radio 4 LW, they have separate antenna, albeit with one of them (5 Live) doubling up as one of the support towers for the large long wave T antenna slung between the two large towers on site. Although I suspect the plan would be to move 5 Live to the currently unused Absolute / Virgin antenna eventually so they can demolish the long wave setup.