All posts by Dave Lindsay
Below are all of Dave Lindsay's postings, with the most recent are at the bottom of the page.
david denness: There's no easy answer, other than to say you might be better off to go with satellite (free-to-air Freesat assuming you don't wish to subscribe to Sky).
The fact that aerials are pointing in all directions in your locality (as seen on Street View) is testament to it being a poor reception area, owing to it being at sea level.
Here are plots showing the terrain between you and the four transmitters:
Beacon Hill:
Terrain between ( m a.g.l.) and (antenna m a.g.l.) - Optimising UK DTT Freeview and Radio aerial location
Stockland Hill:
Terrain between ( m a.g.l.) and (antenna m a.g.l.) - Optimising UK DTT Freeview and Radio aerial location
Exeter St Thomas:
Terrain between ( m a.g.l.) and (antenna m a.g.l.) - Optimising UK DTT Freeview and Radio aerial location
Dawlish:
Terrain between ( m a.g.l.) and (antenna m a.g.l.) - Optimising UK DTT Freeview and Radio aerial location
I would say probably Exeter St Thomas, or even Dawlish, as you would appear to have line-of-sight with them. You don't have line-of-sight with either Beacon Hill or Stockland Hill, which is undoubtedly the difficulty in receiving from them.
The thing is that the St Thomas transmitter doesn't provide all the channels -- it not carrying COM4, COM5 and COM6. Both Beacon Hill and Stockland Hill carry these channels at lower power and less rugged signal mode than the PSB channels (which are those that St Thomas gives you).
This begs the question: which channels are you having difficulty with and which transmitter does your aerial point to?
This is because there are a number of possibilities, such as:
- Your aerial points to one of the full service transmitters (probably Beacon I think) and the PSBs are good but the COMs are variable.
- Your aerial points to St Thomas or Dawlish and you have good reception of PSBs and no or intermittent reception of the COMs (which are being received from another transmitter).
Digital UK publishes a full list of Freeview services, including multiplex (PSB, COM etc):
Digital UK Industry - Channel listings
If you refer to the following you will in fact be viewing on service of each of the six main multiplexes:
PSB1 - BBC One
PSB2 - ITV
PSB3 - BBC One HD
COM4 - ITV3
COM5 - Pick
COM6 - 4Music
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The Budleigh Salterton transmitter is said to be a Signal Frequency Network with Beacon Hill, but a relay of Stockland Hill. Is this not an oxymoron?
The service area overlaps with Beacon Hill, according to the coverage maps on this site. So in order for it to work it must be an SFN. So, surely it must be a "relay" of Beacon Hill and line fed in order that it be in sync.
The mb21 Gallery shows there's a single horizontally-polarised log pointing in the direction of Stockland:
mb21 - The Transmission Gallery
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Sharon: The most common answer to the issue of no channels being received is where a signal amplifier (booster) is being used and it failing or its power being turned off. This situation includes a communal aerial system, such as found in a block of flats.
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We know where Winter Hill gets its name from, but it's certainly not winter up there now!
Video: Aftermath of huge moorland blaze on Winter Hill - Manchester Evening News
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Louise Knight: If it's a "high-gain" wideband aerial then it won't be giving "high-gain" on Group A channels, which are those Crystal Palace uses exclusively. For that reason, it should be a Group A aerial.
See:
Crystal Palace Transmitter
Examples are here:
Gain (curves), Again
Along the bottom are channel numbers and Crystal Palace uses 22 through to 35. You will note that the high-gain widebands, XB22WB and DY14WB have much less gain on those channels.
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Louise Knight: You can use the cabling installed to the satellite dish for connecting the aerial to, but ensure connections are watertight obviously.
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Brian Murray: If it's to be a yagi then it should be a Group A (not wideband) or if it's a log periodic then it's likely to be wideband.
See:
Rowridge Transmitter
All yagis have a gain curve which slopes downwards as you go to lower channels. The wider the 'band' of the yagi the more of a compromise it is. For examples to understand this, see:
Gain (curves), Again
The XB22WB , for example, has a good high gain on high channels, but not so on low, Group A channels. The thing is that Caldbeck uses Group A channels exclusively. Hence, using a high gain wideband aerial on it gives plenty of gain but not on the channels it uses. This is why you should use a Group A if it's a yagi.
The question is, is lack of gain really your issue? What's your reception of the lowest power multiplexes like?
COM7 - C32
COM8 - C35
Freeview services by multiplex listed here:
Digital UK Industry - Channel listings
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Tricia Camm: Yes, but there's a but....
Looking at predictions you may only receive PSB channels, probably from the Whitby relay, this being because reception of all channels from Bilsdale might be out of the question due to being in the Esk Valley. A full postcode would allow us to gauge your chances.
Digital UK publishes a full list of Freeview channels by multiplex here:
Digital UK Industry - Channel listings
Organise the table by "Mux" (multiplex) and you will see services of the three PSBs (or two if it's not HD).
Assuming you're receiving from Oliver's Mount then you will have all channels. You will also get BBC Yorkshire and ITV Yorkshire. But in the Esk Valley you will get BBC North East & Cumbria and ITV Tyne Tees.
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Tricia Camm: Oh dear.
Before you posted the postcode I was looking around Ruswarp on Google Street View and noticed that the houses to the south of the Esk on Glen Esk Road have Bilsdale-facing aerials. A check showed that, while it can't be seen, the obstructions aren't anywhere near as bad as to the north of the river.
Ruswarp Bank is, well, a slope. If it's the top you're at, then I've spotted one Bilsdale aerial. To recap, Bilsdale may give you all the channels but Whitby won't.
That said, the lower down the Bank you are to live, the less your chances of easy reception from the Whitby relay, this suggested by a terrain plot I did. This is because the transmitter might be out of sight:
Terrain between ( m a.g.l.) and (antenna m a.g.l.) - Optimising UK DTT Freeview and Radio aerial location
It's a not awfully acurate, the plot, because it samples ground levels at fixed intervals and as it's such a short distance coupled with your new house being on a slope.
It's coming up on ten years since the Whitby TV transmitter move debacle. The transmitter, as everyone who visited the town would know (even if they didn't realise what it was) was situated at the top of the East Cliff, overlooking St Mary's Church. Due to coastal erosion it needed re-siting. Following a public vote it was moved to an industrial estate...because it wouldn't be visible. And to be able to receive from it, needs to be seen! An absolutely stupid idea leaving joe public to decide, as the people of Sandsend will tell you.
News reports here:
mb21 - The Transmission Gallery
So, it could be that there's no terrestrial aerial for a reason! A terrain plot suggested you might have been able to see the old transmitter.
In short, if you are to live near the top of the Bank, then you "might" be able to receive all channels from Bilsdale, but because you can't see it reception may be variable, such as depending on the time of year. If not, then you may have to go with Whitby, with its limited channels, or else go with satellite. Free-to-air Freesat is available if you don't wish to subscribe to Sky, and Freesat does "Freetime" which I believe is similar to what YouView is to Freeview.
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Thursday 11 June 2015 9:23PM
Demetrius Skortou: If the fault isn't with your own wiring or equipment, then it's the aerial system which is at fault and therefore the party responsible should be notified.
At your location, with the transmitter being only 5 miles away with clear line-of-sight, too high a signal level is very much a possibility here. The system's amplifier probably wants turning down a bit.
Some systems are fitted with filters so as to only allow through those channels (frequencies) used by the designated transmitter. If you are not receiving the newer multiplexes then, at the same time as fixing the fault, get the engineer to enable them, these being:
COM7 - C33 - 106 BBC Four HD
COM8 - C35 - 111 QVC+1
L-LON - C29 - 8 London Live
There's also the possibility that 800MHz 4G services could be overloading the amplifier as well. Either way, it's up to the party responsible to get an engineer.
Too high a signal level can appear as too low a signal, or dips in quality. It's like having the volume on a sound system set too high -- the signal distorts and does so to differing degrees depending on the sound.