All posts by Dave Lindsay
Below are all of Dave Lindsay's postings, with the most recent are at the bottom of the page.
stuart smith: Whereabouts are you in Haywards Heath?
Did you have Freeview reception before switchover? If so, did you get all the channels? If you were missing channels, which ones?
Did you have your aerial replaced with a wideband aerial?
Are you using a communal aerial system such as in a block of flats?
Heathfield formerly used C/D channels (top third of the band) for analogue. C41 is the lowest which makes it Group B (middle third). Consequently some C/D aerials may not function too well whilst others will. If you have a C/D aerial in a poor reception area, then it might need to be replaced.
Contract aerials are the cheapest and C/Ds can have poor gain below their intended frequencies.
If you answer the above questions it might help to home in on whether this is the problem.
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Ian Foord: I put the post code BN22 0EP into the BBC Reception website (www.bbc.co.uk/reception) and selected the options to say I had a problem with reception of Freeview TV.
Understandably there are notifications about the DSO in the early hours of Wednesday.
However, Hastings shows "from 16:19 on 13 Jun". Heathfield reports "No problems".
So whether it is off-air or not, BBC Reception doesn't seem to say.
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Mike Hall: This site is an independent one and not connected to any of the companies involved in broadcasting.
Bilsdale is undergoing engineering works in preparation for switchover. See the note at the top of the page.
I've never understood why Yorkies would want to watch Tyne Tees, unless they couldn't receive Yorkshire of course. I know that Bilsdale comes in strong, particularly in the north of the city, but why watch news about the north east if you don't have to?
As a fellow Yorkshireman, I want to hear about what's going on in God's Own County!
I reckon that you're on a communal aerial, so tell your landlord that the aerial needs turning to face Emley Moor!
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Alison: Can you post the make and model of your receiver? Some older models won't work after switchover.
BBC signals have now "switched", and therefore affected models will loose the ability to receive BBC channels. The model number will help determine whether this is the case here or not.
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Kathie: Yesterday, ITV4 etc from Dover is currently on C55, so if your set has manual tuning, try tuning to it.
If you can't get it, it could be that previously you were "only just" able to receive it due to its weak strength. The strong BBC signal may have had an adverse effect on reception of other channels. This should correct itself when you retune on 27th.
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Ian Foord: Sorry, that should that BBC Reception reports for Hastings: "HD Digital TV Off Air from 16:19 on 13 Jun".
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Rob: If you receive your TV from Waltham-on-the-Wolds then have you had your aerial replaced? You may have had it replaced to receive digital TV before the switchover which happened last August.
If your aerial is pointing at Waltham, then bring up the signal strength screen whilst tuned to Quest and check that it is tuned to UHF channel 29.
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Mike Gordon: I don't think that the problem could be too high a signal strength (which can be rectified by attenuation).
The tall aerial masts can clearly be seen on the Bird's Eye photographs on Bing Maps and these tell a story.
The problem would appear to be that you live low down and that you are receiving the signal over the brow of a hill, and are close to the hill at that. The problem of the signal going at night is probably caused by the vegetation on the hill or slope getting damp and acting to reflect the signal away.
To understand this, imagine that the signal was a large beam of light. Due to the fact that you're over the brow of the hill of don't have line of sight, you're trying to pick up when light comes over the hill.
Now consider when the sun is low to the ground and shining through trees. The trees cause shadows and as the wind blows, the light changes. Now apply this understanding to what's happening to the signal to your property.
I have set out below an analysis that shows there are a number of groups of trees that are likely to be problematic.
You probably saw the effects with analogue. I expect that when it was wet and windy it be particularly bad as not only would the trees be acting to reflect the signal away because they're wet, but the bits of signal that get through would be changing owing to the fact that the trees were blowing about. Maybe it was different to differing degrees at different times of year, the signal getting better when the leaves fall of the trees.
I did this plot of the signal path from Crystal Palace to your house:
Terrain between ( m a.g.l.) and (antenna m a.g.l.) - Optimising UK DTT Freeview and Radio aerial location
Click the link below the plot on that page to view a map of the area between the two points.
I zoomed out so that both points were visible on the screen. Holding a ruler up to the screen I found that the length of line to be 22cm. The distance to the transmitter is 22.1 miles, so I then looked at what's on the ground in the first mile and a half away from your property. This is the red bit marked on the plot and appears to be roughly up to Breakspear House or thereabouts.
The trees at Old Orchard Lodge would appear to be in the way and quite close at that. The signal path intersects Church Hill, somewhere near Countess Close. Assuming that it is close to the ground, you have the buildings there as well. The trees your side of Dovedale Close, near Chestnut Cottage look as though they could just be in the way. The line doesn't quite intersect them, but the point at your end isn't quite on your house. Then there are trees near Breakspear House as well, which is about a mile and a half away, so I think that's your lot.
Everything further away from you would appear to be under the line of the signal. That is, Bayhurst Wood Country Park, for example, is in a dip and therefore the signal goes over the top of it.
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The Commercial multiplexes, which include ITV3, Pick TV, Yesterday, Sky News and others use a signal mode that is more susceptible to break-up with poor signal than the Public Service ones (which carry BBC, ITV1, ITV2, C4, C5 etc.
The reason the Commercials do this is so as to fit more services in. This obviously comes at the expense of some fringe viewers.
Different receivers having differing levels of sensitivity and tolerances. This probably explains why some work OK and some faulter.
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Corin: I've pointed this one out before.
The reason it appears like this is because ITV3 is carried on PSB2 on the Channel Islands owing to the fact that there is no +1 version of ITV1 Channel Television and that the transmitters there are PSB-only.
So it would appear to be a bug. The heading at the top of this page does say "ITV3 (CI)" which is different to "ITV3" as far as this site is concerned.
Briantist, can you do something to stop ITV3 from appearing on the comparison page in this way?
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Friday 15 June 2012 3:47PM
KennyT: Err no.
Freeview signals are broadcast by terrestrial transmitters. A satellite dish picks up signals from a satellite.
You haven't given your location so it's not possible to gauge how likely it might be that this is the case, but if you're very close to the terrestrial transmitter, perhaps the lead from the satellite dish is picking up sufficient signal from it due to the signal being that strong.
This could also explain why you have poor reception on your communal terrestrial aerial system. It could be amplifying it too much. If this is the case, then it is the responsibility of whoever maintains the aerial system to put it right. It will probably affect others so you might ask your neighbours.
I emphasise that I make this suggestion on the basis that you "may" live close to a transmitter. Without knowing your location I cannot have any idea whether this is likely or not at all likely.