All posts by Dave Lindsay
Below are all of Dave Lindsay's postings, with the most recent are at the bottom of the page.
Ertriad: That's the lot from Chartham; it isn't likely that there will be more. This is because the Commercial broadcasters only wish to stick with 81 of the largest transmitters (largest by population). Evidently they have decided that the cost to include the 1,000 or so small transmitters like Chartham outways the benefit (to them). That cost would roughly equal that of the 81 main/large transmitters whilst only adding less than 10% to the potential viewer base.
See here for a more in-depth explanation: Will there ever be more services on the Freeview Light transmitters? | ukfree.tv - independent free digital TV advice
The only thing you can do with regards receiving the Commercial terrestrial channels is to investigate the possibility of receiving from one of the transmitting stations that carry them. This will, of course, mean you having to have another aerial and is also not guaranteed.
The other main option for additional free-to-air channels is Freesat.
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steve hooper: I think that the likely answer is yes.
The problem you have is probably due to the difference in strength of the Commercial channels relative to the Public Service ones. The Commercial channels are, after all, 50kW horizontally, which is stronger than some smaller main stations.
The higher power signals could be acting to desensitise your receiver making it more difficult to pick up the (relatively speaking) weaker ones.
You "may" be able to attenuate (all signals) and find a sweet spot where all will work fine, without the need to adjust your aerial. A variable attenuator allows adjustment, and these are usually (up to) 20dB. If you do try this, 20dB might not be enough, judging by your close proximity to the transmitter. You may need another attenuator, say 18dB or 24dB, and have this connected inline with the variable one.
See: Freeview signals: too much of a good thing is bad for you | ukfree.tv - independent free digital TV advice
Attenuators are available for a few pounds from sources such as eBay and Amazon.
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Magnus: Are you talking about analogue reception? Analogue signals only provided the four channels you mention (plus Channel 5 in some areas).
If it is analogue, which I suspect it is, then this was turned off last month.
If you're not sure, then perhaps you could post the make and model of the set you are using so we might check the specification.
If it is a TV, and it does not have the means to receive digital broadcasts (Freeview), then it will need a separate set-top box receiver.
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Esme Read: Freesat may be your only way.
The terrestrial transmitters that cover your area best don't carry the Commercial channels, which include ITV3.
It is very doubtful as to whether you will be able to receive the Commercial channels from Rowridge. Only an installer who is on site can tell you with certainty.
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Simon Jacobs: Ditto Stephen P's post.
You have two unknowns. That is you need the TV tuned in order to use it to help you site the aerial and in order to tune the TV you need to site the aerial where it can pick up all channels.
The answer is to remove one of the unknowns by tuning the TV in using an aerial that is known to work.
Your set-top aerial should be pointed to Rowridge and should be set vertically. Your chances of success diminish as you get more things in the way. For example, it is best to be at the side of the house to which the signal originates.
Whilst I cannot be absolute, a correctly sited set-top aerial at your distance from the transmitter should work fine without any amplification. I emphasise that this is no guarantee that it will work where you want it to work.
I have a Labgear Set-top Aerial and have used it successfully without a booster before switchover when the transmitter was at 10kW at a distance of about 25 miles with pretty good line of sight (at roof level).
I suggest that you look at siting the aerial without any booster. Get a feel for where is the best place.
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Ian P: See Freeview signals: too much of a good thing is bad for you | ukfree.tv - independent free digital TV advice
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Ian P: What you have said subsequently adds weight to the suggestion that the problem is too high a signal level.
As the tuner gets more overloaded, the signal strength meter is of less and less value as they usually start to indicate lower levels being present until such a point where it will say no signal is present when in fact the opposite is true, being that the signal is extremely OTT.
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Steve Swift: Crystal Palace uses channel numbers 22 to 30 and Hannington uses those from 39 to 47. Thus if you unplug the aerial lead for the part of the scan of Crystal Palace channels, it won't pick them up.
The scan runs C21 to C69, so if it only gies a percentage on the scale as it scans, then you can convert.
Should the device, at a later time, take it upon itself to scan and then change the tuned channels to those of Crystal Palace, then you will have to look at installing a filter to block Group A channels.
For information and an example:
Television Aerial Boosters / Amplifiers, Splitters, Diplexers & Triplexers
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Andrew: Whilst BN2 is a large area and signal strength will vary across it, the Whitehawk transmitter is near the centre. In which case, if you are receiving directly from Whitehawk and have good line of sight, then your receiver could be suffering from signal overload:
Freeview signals: too much of a good thing is bad for you | ukfree.tv - independent free digital TV advice
However, if you are using the transmitter at Ovingdean or Saltdean, then they do not broadcast ITV3 and the other Commercial channels. In their main service area, the Commercial signals will be weak or non-existant, so the above does not apply.
As I say, it is impossible to be specific because you have specified an area that has wide varying signal expectations.
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Saturday 5 May 2012 8:27PM
John Slater: If you're picking up BBC Midlands Today instead of BBC Look East, then you're not tuned to Sandy Heath (for BBC One and probably other BBC standard definition channels). If your aerial is directed to Sandy Heath, then receiving a signal from elsewhere may be likely to result in poor reception.
The Digital UK Tradeview predictor suggests that the most likely candidate at your location is Waltham. Most receivers give the UHF channel number (equivalent to frequency) that it is tuned to for any particular programme channel and this is usually on the signal strength screen.
Go to BBC One and bring up the signal strength screen. My guess is that it will say C61, which is BBC standard definition services from Waltham. This is BBC One East Midlands region.
To fix the problem, here's the science bit. The programme channels are broadcast in six groups; five for the standard definition services and one for the HD ones.
See here under the heading "After switchover configuration" for the groups (known as multiplexes or "muxes"):
Freeview multiplexes | ukfree.tv - independent free digital TV advice
BBC B carries all four HD services and is therefore only applicable for HD receivers.
If your receiver has manual tuning, then do the following. If not, then the workaround may be more tricky and I can suggest something to try if this is the case.
The end objective is to be tuned to all five (or six) Sandy Heath muxes with none from Waltham (which I've included in brackets):
BBC One = C27 (Waltham 61)
ITV1 = C24 (Waltham 54)
BBC One HD = C21 (Waltham 58)
ITV3 = C31* (Waltham 29)
Pick TV = C52 (Waltham 56)
Yesterday = C48 (Waltham 57)
* SDN (ITV3 etc) will move to C51 on 9th May. Its transmission power will also go up to its full final level. This is the retune event you have been told about and it therefore only affects services on SDN.
In the list above, I've referred to the first service within each group. Focus your attention on getting these right and the others within each group should be right.
During the automatic tuning scan, it is possible to prevent the receiver from finding certain channels by having the aerial lead unplugged when it is scanning them. Some receivers give UHF channel numbers as they scan and some give percentage. The scan runs from C21 to C69, so if it's percentage only, then you can convert.
It is easier said that done to unplug the aerial at a particular channel due to the speed that the scan runs. However, if you aim to unplug too soon, if you are missing the wanted channels you can add them manually.
All but one of Waltham's muxes are at the top end. You need to avoid picking up 29.
If, for example, you run the tuning with the aerial plugged in and then unplug at 8%, you should get ITV1 on C24. Then use the manual tuning function to add the others.
Or, depending on the design of the receiver, you may be able to run the tuning scan through with the aerial unplugged to clear the channel memory. Having done this, use the manual tuning function to add all five (or six) muxes.