Radio Society of Great Britain reaction: https://rsgb.org/main/radio-sport/rsgb-contest-club/bbc-long...
Rather defensive press release thing from the BBC: https://www.bbc.com/mediacentre/articles/2026/radio-4-broadc...
Long Wave radio era set to end with switch-off
21–30 of 170 posts
Re: Long Wave radio era set to end with switch-off
#22Earlier quoted context omitted.
IIRC, their operation relies on enormous vacuum tubes that the BBC can’t get replacements for any more.
In some way it is short-sited, as radio is a good backup medium for global communications in case the entire Internet ever goes down. Vacuum tubes also aren't vulnerable to nuclear weapon electro-magnetic pulses. However, other than ham radio enthusiasts I guess no one listens to analogue radio anymore.
I got my RTL-SDR to see what I could listen to, and by the time I tuned in, nearly all the short wave stations I could tune to were just broadcasting evangelical religious stuff, or other crazy conspiracy stuff. It's remarkable that these powerful stations spend most of their broadcast day transmitting that content.
Re: Long Wave radio era set to end with switch-off
#23Earlier quoted context omitted.
These transmitters consume insane amounts of power. Per Wikipedia, that's 500 kW of rated transmission power for this one [1], so probably a solid megawatt of grid power input. At 30 ct/kWh, that's 300€ per hour, 7200€ per day and about 2.6 million € a year - for a customer base that is only decreasing. [1] https://en.wikipedia.org/wiki/Droitwich_Transmitting_Station
Doesn't excuse CHU: two 3kW, one 5kW ERP. And by the virtue of shortwave propagation, it could be heard across the world. For the past month and a half (from when the news of its impending shutdown was revealed) I was regularly picking it up in Australia right up until the bitter end.
Wave skip? (Naieve question)
Re: Long Wave radio era set to end with switch-off
#24I wonder how many of the Van Allen radiation belts is held up by this
Re: Long Wave radio era set to end with switch-off
#25Earlier quoted context omitted.
Doesn't excuse CHU: two 3kW, one 5kW ERP. And by the virtue of shortwave propagation, it could be heard across the world. For the past month and a half (from when the news of its impending shutdown was revealed) I was regularly picking it up in Australia right up until the bitter end.
Wave skip? (Naieve question)
https://en.wikipedia.org/wiki/Skywave
Bounce off ionosphere
Re: Long Wave radio era set to end with switch-off
#26Earlier quoted context omitted.
IIRC, their operation relies on enormous vacuum tubes that the BBC can’t get replacements for any more.
In some way it is short-sited, as radio is a good backup medium for global communications in case the entire Internet ever goes down. Vacuum tubes also aren't vulnerable to nuclear weapon electro-magnetic pulses. However, other than ham radio enthusiasts I guess no one listens to analogue radio anymore.
They still broadcast on FM.
Re: Long Wave radio era set to end with switch-off
#27List of longwave radio broadcasters - including those that have shut down. The shutdown list is much longer than those remaining (only 7 remaining).
https://en.wikipedia.org/wiki/List_of_longwave_radio_broadca...
Re: Long Wave radio era set to end with switch-off
#28That is too bad, you would think these could be kept active for historical purposes. But seems these services are all being turned off even though I heard a few were very useful in this day and age.
IIRC, their operation relies on enormous vacuum tubes that the BBC can’t get replacements for any more.
It's hard to believe that civilisation has lost the ability to build longwave radio transmitters.
Re: Long Wave radio era set to end with switch-off
#29IMO, when the last LW transmitter shuts down, the whole band needs to be reallocated to hams. Realistic small-ish antennas are shockingly doable with a capacitance hat, loading coil, and counterpoise.
Re: Long Wave radio era set to end with switch-off
#30Earlier quoted context omitted.
Doesn't excuse CHU: two 3kW, one 5kW ERP. And by the virtue of shortwave propagation, it could be heard across the world. For the past month and a half (from when the news of its impending shutdown was revealed) I was regularly picking it up in Australia right up until the bitter end.
Wave skip? (Naieve question)
HF propagates through skywave (most reliably from 5-30MHz), which is where the signal bounces off the ionosphere.
In the MF (AM broadcast) band, you can observe this at night - in Australia I can pick up the 50kW Melbourne ABC station (public broadcaster) at 774kHz with a good radio, just about across the entire country.
In the LF (longwave) band, the earth’s surface and the ionosphere start to behave more like a waveguide than skywave. This is actually more reliable/consistent than even HF, but you need massive transmitting antennas due to the large wavelengths involved.
HF also generally wins for distance covered per watt - despite the massive power of Radio 4 longwave, I’d have no chance of hearing it reach Australia.