Two rare tungsten-centered, hand-crafted cooled anode modulators (CAM) are needed to keep the signal going, and while the BBC bought up the global supply of them, they are running out.
The service is seemingly on its last two valves and has been telling the public about Long Wave radio's end for nearly 15 years.
Trying to remanufacture the valves is hazardous, as any flaws could cause a catastrophic failure in the transmitters.
BBC Radio 4's 198 kHz transmitting towers at Droitwich.
BBC Radio 4's 198 kHz transmitting towers at Droitwich.
Credit: Bob Nienhuis (Public domain) Rebuilding the transmitter, or moving to different, higher frequencies, is not feasible for the very few homes that cannot get other kinds of lower-power radio, or internet versions, the BBC told The Guardian in 2011.
What's more, keeping Droitwich powered such that it can reach the whole of the UK, including Wales and lower Scotland, requires some 500 kilowatts of power, more than most other BBC transmission types.As of January 2025, roughly 600,000 UK customers still use RTS meters to manage their power switching, after 300,000 were switched away in 2024.
Utilities and the BBC have agreed that the service will stop working on June 30, 2025, and have pushed to upgrade RTS customers to smart meters.In a combination of sad reality and rich irony, more than 4 million smart meters in the UK are not working properly.
Some have delivered eye-popping charges to their customers, based on estimated bills instead of real readings, like Sir Grayson Perry's 39,000 pounds due on 15 simultaneous bills.
But many have failed because the UK, like other countries, phased out the 2G and 3G networks older meters relied upon without coordinated transition efforts.