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Whats the most powerful FM and TV transmitter
fmradiotuner1
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HI
I tried looking this up on Google but all this crap comes up about MP3 transmitters :rolleyes:
Also how far does the signal go on the most powerful FM and TV transmitters
Is it France Info 105.2 which I read was 500KW?
I tried looking this up on Google but all this crap comes up about MP3 transmitters :rolleyes:
Also how far does the signal go on the most powerful FM and TV transmitters
Is it France Info 105.2 which I read was 500KW?
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Comments
Henry
Incorrect - Sandy Heath's, Crystal Palace's, etc transmitters do not 'run an ERP of 1 MegaWatt'... Transmitters do not have an ERP - They have an actual output power. It's the antenna system which has the ERP...
So, do you mean 'most powerful transmitter', or 'most powerful ERP'...??
I think we've been here before, but an example of what I mean, is that, at the FM stations, whereby the ERP is 250kW (i.e. 125kW VP + 125kW HP), the transmitters actually 'run' (operate) at around 30kW. So, the ERP from the above mentioned transmitting site's TV antenna systems might be 1MW, but that's no to say the transmitters run at that power.
Distance is governed by a number of factors, including antenna height & ERP, local topography, etc.
So, could Wrotham's 360kW (albeit a mistake, and no longer the case) be classed as the highest FM power in Britain...??
I have got Radio 1 on 98.8 in Parts of Norfolk all the way down to Summerset.
And Radio 1 is only 120KW to keep the Frogs happy !
Wrotham - The South East of England
Sutton Coldfield - The Midlands
Black Hill - Central & Southern Scotland
Winterhill - The North West of England
North Hessary Tor - The South West of England
Droitwich in Worcestershire is the highest powered radio TX in the UK with 500kW, this is used for BBC Radio 4 on 198kHz Long Wave!
For Medium Wave the most powerful in Europe is RTL on 1440kHz in Luxembourg.
Don't you mean Holme Moss? Winter Hill is only 4KW
Yes, I stand corrected
I always think high power FM from the BBC Nationals came from Winter Hill because its the main TV mast.
Where do Manchester & Liverpool get the BBC nationals on FM from?
Holme Moss (and Llangollen is the strongest in Liverpool City Centre).
The BBC NR from Winter Hill is very directional and mainly a filler for the Preston area.
http://www.mds975.co.uk/txmaps/BBC/National/BBCWinterHill.JPG
Not really surprising as the transmitting stations at Tacolneston & Oxford are RBS off Wrotham...
BTW, Radio 1 from WRT is 62.5kW VP + 62.5kW HP (125kW MP), which is only 3dB down compared to Wrotham's other national transmissions (125kW = 21dBW. 250kW = 24dBW) The difference in service area is very little.
If we're taking AM in to account as well, did someone forget the MW transmissions from Orfordness, Suffolk, plus the VT Communications sites which transmit on SW...
BTW, the BBC tend to state (or at least used to state) transmitter output power for AM transmissions, where as commercial radio/Ofcom tend to state EMRP. A good example of this is 1458kHz from Brookmans Park... BBC GLR used to be quoted as being around 50kW (i.e. TX o/p), where as Sunrise is quoted as being around 125kW (i.e. ERMP)....
BTW, I may be wrong, but I think there's a 2MW LW mast in Poland (it may be Russia). I might be wrong... The grey matter isn't what it used to be.
(It's been fried by too many antenna systems... lol! )
Yes your right!
Don't forget Wenvoe and Tacolneston as well. These also put out 250 kW ERP and again cover huge areas.
Whilst you are usually pretty good, would you like to have another go at this one?
Whilst it may well officially have that figure, I doubt very much that it is still operating at full power; many of the ex-Soviet mega medium wave power transmitters are a shadow of what they used to be for a variety of reasons, mainly technical failure though reducing the power to reduce power consumption is very common. A lot of the transmitters have Russian made valves which have a relatively low life so are under-run to keep them going. These days some have been modified to use Eimac or Thales vales and get 10 times the valve life - but cost real money as when a Russian valve failed they took it apart and replaced what was broken.
There's a system in Tajikistan that uses a high power transmitter and something like 26 masts to form a highly directional aerial - the problem is that the aerial was designed in Soviet days and when the Russians left they also took the paperwork so no-one knows exactly how it works, nor how to adjust it as it is off tune somewhere.
And for high power long wave, there was the Middle Eastern state who built a high power long wave so the Royal family could listen to their radio station wherever they were in the Gulf.
I wasn't sure that this was right - many international broadcasters use 250kW short wave transmitters and a decent HRRS 4/4 array (4 dipoles high, 4 dipoles high with a reflector) can give a gain of between 15dB and 18dB so the erp is in the region of 10MW; 500kW transmitters are reasonably common as well, which doubles the erp. In the 1980s, broadcasters were replacing their services with 500kW transmitters but came to realise that they didn't really need that as if everyone was upping their power, there was no real gain so powers dropped to the 250/300kW level. And it cost a lot.
Reading the article, I see that the aerial has a gain of 31dB with "a total of 3.6 MW of transmitter power" so this is 3600 MW erp (roughly with 30dB gain) so a few hundred times that of the broadcast short wave transmitters. A similiar system was built at Orfordness - the Cobra Mist system for over the horizon radar
Oops... those dBW figures I gave were for 125W and 250W respectively.
(who forgot they were talking about kiloWatts, not Watts... See, I was right, my brain has been fried by too many antenna systems... )
Of course, the correct dBW figures are...
- 125kW = 51dBW
- 250kW = 54dBW
(30dB makes all the difference)Am I right in thinking that the better measure of the likely service area of a transmitter is the higher of the two vertical/horizontal components, rather than the sum of the two?
I believe in the USA they measure it that way, which means that they would describe our mixed polarisation transmitters as being considerably less powerful than we do... (i.e. they'd describe Radio 1 from Wrotham as 62.5kW, not 125kW)
RDS on 95.5 from Monte Bisbino (near Como) has been described as having a 20kW TX plugged into a 5x4 array of 20 vertical yagis pointing at Milan. I don't think that's enough information to figure out the actual ERP, but the information claimed it was "about 1MW".
I did notice when staying in Venice once that a lot of the signals coming from Monte Barbaria (actually 50 miles or more away, although line of sight) came in with strengths I'd more normally expect to find within maybe five miles of a UK high power transmitter site.
In England:
http://www.bbc.co.uk/reception/transmitters/radio/england_fm.shtml
Holme Moss 98.9 89.3 91.5 93.7 M 250kW SE095041
Rowridge 98.2 88.5 90.7 92.9 M 250kW SZ447865
Sandale 97.7 88.1 90.3 92.5 M 250kW NY266398
Sutton Coldfield 97.9 88.3 90.5 92.7 M 250kW SK113003
Tacolneston 99.3 89.7 91.9 94.1 M 250kW TM131958
Wenvoe(see also Wales) 99.5 89.9 92.1 94.3 M 250kW ST110742
Wrotham - 89.1 91.3 93.5 M 250kW TQ595604
And in Wales:
http://www.bbc.co.uk/reception/transmitters/radio/wales_fm.shtml
Blaenplwyf 98.3 88.7 90.9 104.0 93.1 M 250kW SN569756
Wenvoe 99.5 89.9 92.1 94.3 96.8 - M 250kW ST110742
And in Scotland:
http://www.bbc.co.uk/reception/transmitters/radio/scotland_fm.shtml
Black Hill 99.5 89.9 92.1 95.8 94.3 - M 250kW NS828647
Sandale 97.7 88.1 90.3 92.5 94.7d - M 250kW NY266398
And Northern Ireland:
http://www.bbc.co.uk/reception/transmitters/radio/n_ireland_fm.shtml
Divis 99.7 90.1 92.3 - 94.5 M 250kW J286750
And the big daddy of them all. of course, is Radio 4 long wave:
http://www.bbc.co.uk/reception/transmitters/radio/medium_long_wave.shtml
Droitwich 198 500kW SO929663
If you touch even the antenna that transmits the tv, digital, sound ect You are sure to get what is called an RF electric shock.
Transmitter will have to be switched off if the antenna needs adjusting.