Comments by "Bond25" (@Bond2025) on "Thousands Rely On These Antennas - But What Do They Do? - Buxton" video.

  1. What really annoys me is fancy mixed polarisation aerials - often set as a beam on a 45degree angle or 4 folded dipoles at 45degree angles on 4 poles or those X shaped ones with 8 or 12 elements. All of them are a total waste of power, stations are having to pump in 4 times the power to get any coverage because they are inefficient. I looked at the old JUICE FM TX in Liverpool a few years ago and they were using a compromised antenna with 100Watts and gain of -2.5dB, so were allowed to turn the RF up to around 140Watts to give 100W at the aerial to overcome feeder loss. It was a dipole that had each element bent out so it was part horizontal, then vertical. It only give a combined H/V radiation pattern with 50Watts in each plane in theory. They would have been better using two dipoles - or just using vertical polarisation. I am not even sure if it is still in the Cathedral. You can go on the roof for a tour of the cathedral in Liverpool most days and look at the transmitter room if you're lucky and all the aerials on the roof. There are PMR, police, mobile companies, coastguard, taxi service and radio stations.
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  2. On 70cm i can get the Isle of Man using 5watts in to a 8dB vertical. I'm around 100miles away. On 2m i can get further than that. It depends on height. With Meshtastic on 868MHz my range is less than a mile in some directions - but i can get people mobile on Winter Hill from 40+miles away using a 5dB aerial on a bedroom windowsill. Another person is 5miles away 200ft up in a flat.
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  3. mb21 and the RA has a list of who uses which site
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  4. Part of Betwys-Y-Coed never had TV or radio - not sure if they have relays now. They only just had phones and when internet took off around 1995, speeds were 4-5Kbps using Demon, or attempting to via 14K4 and 28K8 modems. I used to go on holiday every year and stay near a farm, so got to know the family that run it. They couldn't even get MW stations unless they hooked up the radio to miles of fence. We did that with a CB one day and the result was amazing from about 3miles of barbed wire running 3ft off the road, then up a hill. There were no mobiles back then and no VHF radio, SATTV was not common.
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  5. It's actually quite boring inside them! A few racks with equipment in plain cases, a few power supplies, a backup system with batteries...trays with coax and a few circulators and diplexers, it's a right let-down. The newer ones might have computers or a phone. One in Wales had it's own BT phone inside, but it sounded like the person using it was in a cave due to the brick and concrete building. The most exciting thing i found in one was a 15year old chicken pot noodle, a screwdriver and wire cutters. The Home Office ones were more secure with electric fences, some not even switched on, cctv and alarms hooked up to BT RedCare. One used for police had ANPR cameras! Not that exciting inside really, i am not sure what people expect.
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  6. It is a legal requirement for site operators to know what they have operating as they get called when there is a problem. Any loss of service causes a problem and interference is a legal issue. Everything is licenced and the operators and RA check regularly. They also do spot checks. In the days of pagers around 94 i was at a hilltop site in Wales when the RA turned up to do field strength tests. A VHF pager was splattering and when i let them in the building they found the 10Watts from the TX was going via a 400Watt RF amp in to their own aerial on the mast - around 137MHz. They had the site owner and company rep there within 45mins and took the amp away. Had they not complied, the equipment was going to be switched off and removed. The way the sites work is that you have a few wideband VHF and UHF aerials for general use. You can use your own or you can use a wideband RX one for VHF and another for UHF and TX through your own. There are circulators fitted, but it depends what room is left. The old PMR repeaters would use a common receive aerial at the top of the masts and TX on their own. That's because the common aerial would be a 68-88MHz, 160-180MHz for example, or 440-460MHz, so never cut for one frequency, but good enough in that location. That was only one part of the mast and buildings. There were relays, links, commercial stations and 70cm / 2m repeaters in some. Now they have TETRA and Cellular. Sites i went to were never alarmed either. It was just a case of being issued with keys. One site had about 8 padlocks all joined to each other and wrapped around a gate, you opened your own to get in! Sadly, pirates would install equipment on some of them with 10GHz links, steal electric and splatter and interfere.
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  7. Stacking beams one on top of the other is for gain, handy for longer distances. You might only get 3dB more, but that is double, so worth it. Putting them side by side tends to be for dealing with reflections, you can slide one beam forwards or backwards to eliminate multipath interference - or it is to tighten the angle of reception but keep the same gain. Think of changing from floodlight to torch beam. I don't think they would use two lots of RX. I used both methods to overcome rubbish signal when Winter Hill was on reduced power as it was being changed to Digital. 2 x 10 element group CD wasn't good enough. 1 with no preamp meant no CH4/5 and breaking up ITV. A preamp got ITV and CH4 was still bad. I tried the 2 x 10 element stacked by the length of the dipole. Then i got 2 x 18 element and that was better. I had an indoor preamp at the time, but you can't amplify something that isn't there. I used a masthead preamp and got a good picture for years. Others were being ripped off, a neighbour paid £250 for this huge aerial and coax and it kept breaking up. They even had one about 6ft long pointing to Wales and that was no good. My TV aerial now is a log periodic with amp on it that's on the pole supporting a washing line in the garden. Perfect signal. It was only temporary after getting shut of VirginMedia for doubling my bill, but it works really well, so i left it,
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  8. In the UK you need Planning Permission from your local Council. If it was in the middle of nowhere, not near roads or houses, you might get away with just doing it, but you run the risk of aircraft hitting it. It depends where it is,
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