All posts by Dave Lindsay
Below are all of Dave Lindsay's postings, with the most recent are at the bottom of the page.
Syd Wall: The answer must be that "something" has changed. Assuming that this is not with your box, then it must be a change, perhaps a slight one, in the signals (perhaps strength) from Sutton Coldfield and/or Lark Stone which means that the "decision" as to which it goes with for the "main" channels is different.
How might this be proven? Where might it get you?
Automatic tuning functions are not infallible when fed with duplicate signals from more than one transmitter. This was the case in the days of analogue and is still true with digital.
| link to this comment |
David Hathaway: Depending on your location you could only receive the Public Service (PSB) Freeview channels. This will be the case if you are on the Monmouth transmitter. See above for the services it carries.
| link to this comment |
Tim: C29 uses DVB-T mode.
I don't believe COM8 on C35 is on air yet, although I'm not in the area so can't check. COM7 is being introduced from transmitters but COM8 has yet to be turned on anyway.
C33 is on air. Perhaps the lower power is the reason you can't get it, especially as you are relying on a set-top aerial facing away from the transmitter.
I can't believe that an appartment block does not have a TV aerial system!
| link to this comment |
Dave: BT is correct - the transmitter network and the receiving aerial system is nothing to do with it.
Retuning is only necessary if the receiver is tuned to the wrong transmitter. Where this is found to be the case then this cannot possibly be the fault of the transmitter to which it is not (but should be) tuned!
The point is that the receiver will give the best picture it can on the channel/frequency it is tuned, based on what is being fed into it from the aerial lead.
| link to this comment |
Tim: No, there are no plans.
The two new HD muxes will available from 30 transmitters, usually on lower power than the rest.
C29 will be a bit higher power than C33 and C35, but still lower than the main six.
Perhaps you should get a petition together with your neighbours to have an aerial system installed.
| link to this comment |
Dave: Your point that this has happened for no apparent reason hits the nail on the head - that is the reason isn't apparent.
In order to solve an issue we must first accept that it exists. Giving in to frustration and saying that the problem lies elsewhere and is someone else's job to fix may get us nowhere.
Reception issues generally fall in to one of three categories:
1. Some fault with the viewer's equipment, wiring or aerial.
2. A change along the signal path (line) between the transmitter and receiver.
3. A fault with the transmitter.
Looking at your location, I think that it number 2 is quite possible (that's point number 2 above rather than some other "number 2"). Click "Terrain plot" at the side of your posting and you will see that the line (signal path) from your location to the top of the transmitter runs pretty low to the ground for about 4km (2.5 miles). Hover your mouse over the plot and the pointer will change to a crosshair. Click a point and it will show a map with a black marker which has a down-arrow on, this being the point you clicked.
The point 2.5 miles from you is Keycol Hill, just east of Newington Railway Station. I suggest that anything that has been built between you up to approxiamately Keycol Hill could "potentially" have an affect on your signal.
Before you consider the above, however, I would start off by checking that the BT Vision box is tuned to Bluebell Hill. If it is found to be tuned correctly now, should reception go poor then check it again (for the service tuned to).
The tuned UHF channel is usually given on the signal strength screen. There are five for standard definition and for Bluebell Hill they are as follows:
PSB1 - BBC One - C46
PSB2 - ITV - C43
COM4 - ITV3 - C45
COM5 - Pick TV - C39
COM6 - 4Music - C54
(PSB3 carries HD services only, so I haven't included it.)
Each signal, known as a multiplex, carries multiple services. A full list of service by multiplex is here:
DTG :: DTT Services by Multiplex
So when viewing the signal strength screen on BBC One, or any BBC service, it should be tuned to UHF channel 46 (C46), for example. CITV is carried on COM4, which is on C45.
The box could possibly be tuning to Crystal Palace, which slightly clockwise of Bluebell Hill. Its five standard definition channels are (just in case the show up on your check): 23, 26, 25, 22, 28. If it is found to be retuning itself then this is your issue and therefore we need to look at what could be done to stop it doing this.
I reitterate, if it's found to be tuned to Bluebell Hill then retuning is a waste of time and the problem lies elsewhere.
Incidently, I notice you've only made mention of the BT Vision box. Does the TV not have Freeview built-in and if so, how does this fair?
| link to this comment |
Dave: To summarise my posting above:
Is this signal one that is being broadcast by Bluebell Hill (showing as being tuned to UHF channel 39, 43, 45, 46 or 54)?
Or is it coming from Crystal Palace (22, 23, 25, 26 or 28)?
The UHF channel number is usually shown on the signal strength screen (I'm not familiar with the BT Vision box, so apologies if the information isn't given).
| link to this comment |
Ruth: This is the effect of a free-market. What you have is thanks to the "Public Service" obligation of the BBC, ITV, Channel 4 and Channel 5.
See here for an explanation of why the UK now has a two-tier system:
Londonderry (Northern Ireland) Freeview Light transmitter | ukfree.tv - 11 years of independent, free digital TV advice
You're not likely to receive more channels from any other transmitter. Probably best to go with satellite (e.g. Freesat) if you wish to increase your number of channels.
| link to this comment |
Paul: If it's a yagi type then Group K it must be for both transmitters.
The Wrekin
Sutton Coldfield Transmitter
A wideband isn't necessary for both these transmitters. At present The Wrekin uses Group A and Group B channels (which covers Group K).
Sutton Coldfield broadcasts the six main multiplexes only on Group B channels. It will carry the two new quasi-national HD multiplexes on C33 and C35, so just within and just below Group B. However, it is doubtful that they will be available to you, them being on much lower power.
In the future the channels used are only ever going to move downwards, in order to make room for mobile services. It is for this reason that, for Sutton Coldfield, the Group A base should be covered.
The Wrekin is lower powered than Sutton Coldfield. If there are aerials on it when it is closer then you must ask why. Both broadcast the same BBC and ITV variants so there is no difference there. It's doubtful that you will get the new HD muxes from Sutton Coldfield so from a channel choice point of view there is probably nothing.
Even still, with a Group K aerial you could always try Sutton Coldfield or turn it to face The Wrekin if the Sutton Coldfield HD mux on C33 (which comes on air on 10 December) isn't available.
What's wrong with the current Wrekin aerial? If it's still a Group A one then it might not be good enough for the COM channels which are in Group B.
| link to this comment |
Sunday 1 December 2013 10:45PM
J. Mooney: I wouldn't think that a booster should be required at 1 mile from a 400W transmitter, unless perhaps for the purpose of distributing to more than one room.
Have you tried removing the booster?
Are you unable to receive all channels from Sutton Coldfield? I looked on Streetview at your road and all the aerial I can see are on Sutton Coldfield. They are higher gain and higher up than normal, so reception isn't easy.
With Kidderminster you only receive the Public Service (PSB) channels.
Also, check that the TV is tuned to Kidderminster transmitter and not Sutton Coldfield. Bring up the signal strength screen on the following and observe the UHF channel number that it is tuned to:
BBC One = C49 for Kidderminster; C43 for Sutton Coldfield
ITV = C58 for Kidderminster; C46 for Sutton Coldfield
BBC One HD = C54 for Kidderminster; C40 for Sutton Coldfield
If you have ITV3, Pick TV or 4Music then these must be coming from Sutton Coldfield as Kidderminster doesn't carry them.