All posts by Dave Lindsay
Below are all of Dave Lindsay's postings, with the most recent are at the bottom of the page.
Ian: No, definately not a 4G issue because there are no 4G signals at 800MHz in your area.
You have asked the question as to whether this might be 4G interference. Are you seeking to find a solution or is that it?
If you are looking to find a solution, then you have identified the problem! You said you are now picking up BBC Wales which means that you must be tuned to a transmitter to which your aerial wasn't installed for (that is, one to which it doesn't point).
| link to this comment |
Ms K: There are a number of possibilities which must really be worked through one at a time.
First and foremost, ensure that the TV is tuned to the correct transmitter - that is to the transmitter which the aerial faces and not a different one. Don't assume that the automatic tuning function will see you right, particularly as there are at least two transmitters that may be picked up. Information on this is at the end of this message.
At your location, Ilchester Crescent and Mendip are on roughly the same bearing. Ilchester Crescent's signals are vertically polarised, hence aerials for it are vertical (elements up/down). Mendip is slightly anti-clockwise of Ilchester Crescent and aerials are horizontal (elements flat).
I looked on Streetview and there is a mixture of the two transmitters being used on your road.
Number 10 has two aerials both which are vertically polarised, but the reflector (the bit at the rear) on the top one is incorrectly fitted as it is horizontal. Also, what is presumably the aerial lead emerges from behind the drainpipe and is probably trapped in the window which is likely to be doing neither the cable nor the window mechanism any good. All these things could be impacting on the TV signals received.
I suggest that you put the attenuator to one side and look at whether the TV is tuned correctly first. Once it is tuned correctly then nothing positive will be achieved by tuning it again - it gives the best picture it can based on the signal that is being fed into it. In such circumstances then your attention must turn elsewhere as to a solution.
Is there one aerial feeding both points or are there two aerials?
If there are two aerials and they both face the same transmitter (i.e. both horizontal [Mendip] or both vertical [Ilchester Crescent]) or there is a single aerial then start in the conservatory. Check that the TV now in the conservatory is tuned correctly. Having done this tune in the new lounge TV by connecting it to the aerial feed in the conservatory. Check that it too is tuned correctly. Once you have both sets tuned correctly leave the tuning alone as any poor reception has its cause elsewhere.
The long lead you mention (or indeed any lead) must be swapped with another, such as the one from the conservatory, to discount it as a possible cause, but ideally only after the TV is tuned correctly.
-----
There are six Freeview signals, each of which carries multiple services, a "service" being BBC One, BBC Two etc. There are five for standard definition and one for high definition.
Bring the signal strength screen up on the following five services (six if it's a HD set) and observe the UHF channel number tuned:
BBC One | IC=C41 | M=C49
ITV | IC=C44 | M=C54
BBC One HD | IC=C47 | M=C58
ITV3 | IC=C42 | M=C48
Pick TV | IC=C45 | M=C56
Film4 | IC=C39 | M=C52
I've abbreviated the transmitter names to "IC" for Ilchester Crescent and "M" for Mendip. If the TV doesn't give the UHF channel number but instead only gives a frequency in MHz then let me know and I will give you the equivalent MHz frequency for each.
If your aerial faces Mendip you may find that Ilchester Crescent is tuned, particularly as its channels are lower and therefore picked up first during the scan.
You may be able to avoid the unwanted one by having the aerial unplugged during part of the scan, but if you provide more information then more accurate advice on achieving that can be offered.
| link to this comment |
G Higgins: Presumably this is in reference to PSB1 (BBCA) from Keighley. Possible interference from Winter Hill maybe.
| link to this comment |
Simon Van Hear: This is good - that there is acknowledgement of a fault as it is the first step to rectification.
| link to this comment |
Mike : If you have an aerial Mendip and one on Rowridge, but the latter's COMs aren't good then either combine the feeds with a diplexer or have a separate set-top box connected to the Rowridge aerial specifically for viewing of regional content.
Online TV Splitters, Amps & Diplexers sales
UHF Bandpass filters, amplifiers for terrestrial TV
The diplexer necessarily need not be on the roof. Having it behind your TV set means you can remove it easily if needs be.
| link to this comment |
Jeff: Try a manual scan of UHF channel 58. If this doesn't work with it in situ then take it to another room with an aerial outlet. Once you have the missin channel tuned then don't retune as the TV will give you the best picture (if any) for the signal that is going into it.
The aerial lead (from the wall socket to the TV) could be faulty so it is worth swapping it for another to see if it makes a difference.
| link to this comment |
Lee: Based on the prediction of transmitters that may be available at your location, you should check to see that your TV is tuned to your intended transmitter.
Crystal Palace is roughly on the same bearing as Bluebell Hill and the former uses lower channel numbers and is therefore picked up before the latter during a scan.
You have posted on the page for the Faversham transmitter this carrying only Public Service (PSB) channels, so if your aerial faces it and you are receiving Commercial (COM) channels then you are receiving them off beam of your aerial. If your aerial doesn't face Faversham then it could have been picked up.
Programmes not recording could be caused by having some channels tuned from one transmitter and some from another.
There are six broadcast channels to check (five if it's only a standard definition receiver:
PSB1 | BBC One | C46
PSB2 | ITV | C43
PSB3 | BBC One HD | C40
COM4 | ITV3 | C45
COM5 | Pick TV | C39
COM6 | Film4 | C54
The above are the channel numbers for Bluebell Hill, it being west with your aerial horizontal. Bring up the signal strength screen on each of those services and identify whether they are tuned to it or elsewhere.
For example, BBC One should say UHF channel 46.
If any are in the 20s then run the aerial scan with the lead unplugged initially and plug in when it gets to 30% or past UHF channel 30. Then check them again.
Further guidance can be given on reply.
| link to this comment |
Lee: If your aerial is facing the Faversham transmitter then it only broadcasts the Public Service (PSB) channels. The Commercial (COM) channels are only available from the largest transmitters. Therefore there is a small proportion of the population who can only receive the PSB channels.
If you are picking up the COM channels (ITV3, Pick TV, Film4 etc) with your aerial vertical and pointing to the Faversham transmitter then you are receiving them off-beam of your aerial and therefore that explains why reception may be hit and miss - that is because the aerial is only designed to receive from the direction to which it faces.
The full list of Freeview services is here:
DTG :: DTT Services by Multiplex
| link to this comment |
Monday 24 June 2013 8:33PM
john Broadhurst: The West Runton relay (aerial vertical on bearing of 250 degress) is the most likely. BBC One is on C26 and ITV on C23, this information usually being given on the signal strength screen.
Reception of the COM channels is not a given, even though reception of PSB channels is possible.
It might be worth walking around nearby streets to see if there are any aerials on Belmont or Tacolneston.