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Exploring a transmitter tower

MikeSh

MikeSh

Well-Known Member
YouTube video that might interest some people.
Basically a walk-round of an American FM/AM transmitter with some digital/HD (if I understood it right).
Exploring a 1 MILLION Watt FM Tower
About 18 minutes.
Initially I skipped through a lot but then was interested enough to go back to watch from the beginning.
 
Black Hole said:
Wow. Get the size of that co-ax!
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When I skimmed through first time I thought they were wave-guides, like radar.
I'd like to have seen how they 'translate' into the antenna up on the mast, but clearly that was not possible for these guys.
 
I gave up trying to watch this when my YouTube downloader showed the file as being greater than 1GiB. Either the downloader is toast or the video is in v high quality. I was interested, but not interested enough to use that much data on a metered connection!
 
EEPhil said:
I gave up trying to watch this when my YouTube downloader showed the file as being greater than 1GiB. Either the downloader is toast or the video is in v high quality. I was interested, but not interested enough to use that much data on a metered connection!
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Did you try to change the quality setting?

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EEPhil said:
I gave up trying to watch this when my YouTube downloader showed the file as being greater than 1GiB. Either the downloader is toast or the video is in v high quality.
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720p is my default so 125MB and a 20 second download on a PC with Tartube.
EEPhil said:
I was interested, but not interested enough to use that much data on a metered connection!
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A meterered connection? How quaint...
 
1MW ERP so a lot less actually goes up the mast.
[Edit] Having watched the video I see antenna gain was mentioned briefly.
 
Last edited:
All that wasted power running the off-line spare transmitter into a dummy load! You'd think they could use the heat in some way rather than release it to free air.
 
Black Hole said:
All that wasted power running the off-line spare transmitter into a dummy load! You'd think they could use the heat in some way rather than release it to free air.
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I think they only use that when testing it. It wasn't very clear but that was what I took away.
 
Incidentally, the first few minutes covers the question about "how is it 1 million ERP but only 300,000 sent up the cable?". The answer seemed very muddled to me, though I think I get it.

In fact quite a lot of it is a bit unclear, but it's perhaps more off-the-cuff than the first video.
 
MikeSh said:
Incidentally, the first few minutes covers the question about "how is it 1 million ERP but only 300,000 sent up the cable?". The answer seemed very muddled to me, though I think I get it.

In fact quite a lot of it is a bit unclear, but it's perhaps more off-the-cuff than the first video.
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Put simply, the 1MW ERP is the power a simple dipole would need to radiate for a given signal strength at a receiver. But half the power would be radiated above the horizontal and be wasted, so the aerial array is designed to radiate power only where it's wanted, below the horizontal and also in a flattened pattern to further increase the coverage. The 300kW array here gives the same signal levels and coverage a 1MW simple dipole would, hence 1MW Effective Radiated Power.

TV aerials - Yagis, log periodics etc. - work in the same way, favouring reception from one direction to give a signal level many dB over that of a simple dipole.
 
Bit late back with comments, but FOMO kicked in. (Fear Of Missing Out, for the uninitiated.)
Luke said:
Did you try to change the quality setting?
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No, but I have now. I use the command-line youtube-dl (on PC and an experimental "app" on an android tablet) and am not a very skilled user - just the basics. (Although I keep having to chase /df's updates on github everytime yt throttles itself.) When I saw a 2GB download on the files this time I looked for another way and found the solution. Not as easy as your photo.
everthewatcher said:
my default so 125MB and a 20 second download on a PC with Tartube.
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Which is what I ended up with using ytd and the appropriate switch. ( -f "best[height=720]" )
everthewatcher said:
A meterered connection? How quaint...
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No broadband. Internet via 30Gb (currently. sometime 15GB) monthly data on mobile and wifi hotspot or USB tethering etc.

All I need to do now is watch the videos :)

(Apologies for any typing/spelling errors - this PC is on a go slow and taking about 2-5s to respond to a keypress - Argh!)
 
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