All posts by Michael Perry
Below are all of Michael Perry's postings, with the most recent are at the bottom of the page.
Stuart:
Such a low signal strength suggests you have an aerial problem.
Firstly, check all your aerial cables are free from any damage and there is no water ingress. Also check that all the plugs are fitted to cables correctly, if in any doubt replace the cable and connectors. Then check that your aerial is undamaged and has not been moved by winds, etc. Then check that there are no tree directly in front of the aerial. Then check that you are tuned to the Crystal Palace transmitter and not the Wooburn or High Wycombe transmitters which are closer to you (they are 'Freeview Light' transmitters so don't carry all the channels). If you have an aerial amplifier in the system, check it is actually working (just having the power light on does not mean it's working). Likewise, if you have a signal distribution unit fitted, check that is working properly as well.
If you still have such low signal strengths then I suggest you need an aerial contractor to check your system from the roof downwards.
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mark harriman:
Quite simple really, Freeview transmitters only radiate the regional programming for the area they are located in.There are a limited number of frequencies available for each transmitter to use and there are so many channels now that it is not possible to have all the regional variations transmitted from all the more than 1000 transmitters. So they are set up to serve the local area only. The same was true in the old 405 line VHF days and in the 625 line UHF analogue days. Going digital allowed more channels to use the available frequencies at each transmitter - but not enough to have every regional channel available from every transmitter. So only the local ones are available. Add to that the fact that UHF signals have a limited range, in normal circumstances, so a large number of transmitters are needed to cover most of the country - and they cannot all share the same frequencies at present. That may change with further developments of the use of DVB-T2 encoding needed for HD transmissions. but the programmes broadcast from the transmitters will still have a local only nature.
On satellite, the usage of the available spectrum is different and as the radiation pattern covers the whole country, and others to some extent, it is necessary for them to carry all the regional variations so the viewer can choose for themselves. Much higher freqnecies are used for satellite broadcasting so it is possible to carry more channels with suitable encoding.
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MikeB:
Another problem not mentioned in your submission, is that HDMI seems to lack the automatic facility to select the required input on the TV if using an external source (I have yet to find any lead that provides that and I'm not certain the TVs are equiped to do that automatically). I have a Freeview HD TV that has both SCART and HDMI inputs. The SCART input uses pin 8 to select the required input when we turn on the Sky HD box - but SCART cannot provide HD viewing. The HDMI system does not automatically select one of the inputs so if I use an HDMI lead we have to manually select an HDMI input - which can be a pain in the ****! Only when HDMI provides the same automation as does SCART will more people use HD.
I totally agree that the channel allocations on Freeview tend to discourage viewers from seing things in HD. Add to that the fact that the current BBC HD services do not carry the 'local' regional services, so we in Wiltshire get London local news! Will that change when the next raond of changes happens? I'm not holding my breath.
When those issues are resolved, it is likely that more people will watch in HD rather than the 'easy' SD.
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MikeB:
How is it, then, that when we switch our LG set on it starts with Freeview channels selected (usually BBC SD as you said) but when I switch on our Sky HD box with it connected via HDMI, and the SCART disconnected, it doesn't select an HDMI input at all? I've checked the manual and tried all the HDMI inputs and none of them provide that automatic selection of the Sky box signals. I've tried three different HDMI cables in all four HDMI inputs both with the SCART connected and without it plugged in. We have to manually select an HDMI input, which is annoying and less than logical. Hence we tend to watch Sky in SD via SCART and have the option of watching Freeview HD services, albeit having to select 101 etc for the HD channels.
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Jan:
Coalville *is* still covered by the Waltham transmitter as it has been for years (I used to be a senior Engineer for a TV rental company in Loughborough and we serviced Coalville and sorrounding areas for years).
If you look at https://ukfree.tv/transmi…ham, you will see that you are served from Waltham.
The channel numbers you need to tune to are: 49 (for PSB1-BBCA), 54 (for PSB2-D3&4), 58 (for PSB3-BBCB), 29 (for SDN-COM4), 56 (for ArqA-COM5), 57 (for ArqB-COM6), 26 (for LNG), 31 (for COM7) and 37 (for COM8). As some of those channels are lower than a Group C/D aerial can receive, you will need either a Group K or a Log-Periodic aerial to get all the available channels.
Hope that helps?
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Jan:
Please see my answer on the Sutton Coldfield page in response to your same question.
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Stuart:
Start by getting the aerial correctly aligned - that could solve the problem immediately.
If it doesn't them all you can do is to replace the amplifier first and see if that changes things, If that doesn't then you will need to change the distrbution unit and hope that solves it. Note that such distribution units also contain an amplfier and it's not usually a good idea to have two amplifiers in series - unless the reception conditions are so marginal that strengths are extremely weak. But that introduces the possibility if unwanted noise reducing the signal quality to the extent that it becomes unviewable!
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Jan:
Coalville *is* still covered by the Waltham transmitter as it has been for years (I used to be a senior Engineer for a TV rental company in Loughborough and we serviced Coalville and sorrounding areas for years).
If you look at https://ukfree.tv/transmi…ham, you will see that you are served from Waltham.
The channel numbers you need to tune to are: 49 (for PSB1-BBCA), 54 (for PSB2-D3&4), 58 (for PSB3-BBCB), 29 (for SDN-COM4), 56 (for ArqA-COM5), 57 (for ArqB-COM6), 26 (for LNG), 31 (for COM7) and 37 (for COM8). As some of those channels are lower than a Group C/D aerial can receive, you will need either a Group K or a Log-Periodic aerial to get all the available channels.
Hope that helps?
(Copied from the Sutton Coldfield page to assist)
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MikeB:
Our TV defaults to the DVB-T2 tuner first and that is the first on the list of available inputs. So to get to an HDMI input we need to access the input selector page - which is a real pain in the ****, especially for my wife who is non-technical. We can also select the satellite tuner which allows us access to the free-to-air satellite channels which includes the Freesat services - just not on their chosen channel numbers.
The Sky box is an HD type and we can get the HD services on 101, etc but we don't pay extra just to get a few PPV channels that we rarely watch. Likewise we don't pay extra for Movie or Sprt as we don't watch those on Sky - and we hate football, rugby, etc.
So until the auto-selection system present on pin 8 of a SCART is included in the HDMI spec and the software suitably updated, we are stuck with SD mainly - like many people. It was, I believe, an error of judgement to not include the auto-switching needed for automatic selection of inputs, as people have become accustomed to with SCART.
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Sunday 15 October 2017 11:15AM
Kab242:
We cannot confirm whether there was any problem with the transmitter as you have not given a full post code. However, it is highly unlikely that there was any such problem with the transmitter else other viewers would have had the same problem. It is more likely that your aerial cables have some corrosion on the connectors, so please unplug all the aerial plugs and refit them in the same position. That tends to remove any surface corrosion from the plugs and sockets - often curing the perceived problem.
Your TV is likely to have retuned automatically.