All posts by Dave Lindsay
Below are all of Dave Lindsay's postings, with the most recent are at the bottom of the page.
Adelene: What is the make and model number of your son's TV? Some older models will not function correctly after switchover and we can check to see if this might be one.
| link to this comment |
Nikki Halsall: Different equipment has different levels of sensitivity and tolerances for poor signals. There can be strong "poor" signals just as there can be weak "poor" signals.
You could check that both the Philips and the Humax are tuned to the same UHF channels (frequencies). This information is usually given on the signal strength screen whilst a programme channel is selected. The following services are all on different channels (multiplexes): BBC One, ITV1, BBC One HD, ITV3, Pick TV, Yesterday. For each of these on the Philips, see which UHF channel they are on. Then cross-reference with those that the Humax is tuned to. This will establish that the signals to which the Philips is tuned to are the same as the Humax.
You could be in an area served by more than one transmitter, and that your receiver has tuned to the one which your aerial does not face.
Some thoughts on TV reception for a caravan in general are that, if it's a conventional direction TV aerial, such as the "Yagi" shown in the top picture here:
Freeview reception - all about aerials | ukfree.tv - independent free digital TV advice
then:
1. Try turning it and check that it isn't sloping downwards. For example, if it's on a pole where one end rests on the ground, ensure that it isn't causing the aerial to slope downwards. The angle of the aerial could be slightly off (i.e. to one side of the main beam of the signal) and turning it slightly might correct this.
2. Due to the fact that a caravan tends to be low down, the aerial is going to be relatively close to the ground. Try adjusting the aerial so that it slopes upwards slightly, if the fixing allows. It is a "try it and see" sort of thing.
3. A classic mistake of caravanners, barge owners and the like is to have the aerial incorrectly polarised for the transmitter they are receiving. By this I mean that the aerial is horizontal when it should be vertical and vice versa. Copying off neighbours might be of no help because they may have it wrong too! If this is the case, then you might get, what on the face of it, seems to be a good signal, but which, when you wish to watch your favourite programme, turns out to break-up.
If you provide your location (preferrably in the form of a post code), then reception possibilities could be checked upon.
Or, you could use the Digital UK checker here:
Digital UK - Postcode checker
Tick the box to say that you're in the trade and it will come up with a list of transmitters and their channels. It will also tell you the direction from your location. Whether you need your aerial horizontal or vertical is shown in the "Aerial Group" column, denoted as "H" or "V" respectively.
| link to this comment |
Timothy: Try manually tuning to channel 41 (if your receiver allows).
There are a number of possibilities. Where (which transmitter or which direction) was your aerial facing? Is it the same aerial that you're using as before?
Do you get Pick TV and Yesterday?
If you turned it from Sutton Coldfield, for example, you should have changed it from being horizontal to being vertical. Is this the case?
| link to this comment |
Brian Davies: An exact location (preferrably in the form of a post code) is needed in order to give any degree of accuracy. External aerials are generally preferred, but indoor aerials do function effectively in some locations. The design of the aerial may have some bearing.
The first stage of switchover at Hannington happened last Wednesday and BBC standard definition channels are now at full power. On your digital receiver, manually tune to channel 45. You may need to move your aerial to improve the signal.
| link to this comment |
Russ: Ditto Adam B's diagnosis. You will probably only be able receive from the Newhaven relay which will be a Public Service Broadcaster transmitter only. Thus it will carry BBC, ITV1, ITV2, C4, E4, More4, C5, HD and a few others.
Being low down as you are, you won't be able to receive from another transmitter that carries the commercial channels.
| link to this comment |
Tony: No. Classic FM is not on Freeview at all.
Findon will only be a Freeview Light transmitter as it will only carry the Public Service Broadcaster (PSB) multiplexes which will give you BBC radio and TV, ITV1, ITV2, C4, E4, More4, C5, HD and a few others.
Probably best to stick with Freesat I'm afraid. The Digital UK predictor suggests that you will have "marginal variable" reception from the Rowridge main station which does carry the commercial channels.
I believe that the poor reception from Rowridge is owed to the fact that you are in a valley, which is why Finton was installed.
| link to this comment |
Tony: I have had a look around your road on Google Streetview. There are a few houses at the higher end of The Heights and on the grassed roundabout with Ashfold Avenue that have aerials on Rowridge. We have no idea of how well they might work for Freeview now (being as it's lower power).
If they can only get the four analogue channels, then having a larger aerial installed for Rowridge would seem pointless as the same four services are available from Findon with a regular size aerial.
All we can know is that the likelihood of success and stability of reception will be greater after switchover.
If you do wish to get someone in an effort to have an aerial installed to receive from Rowridge (in order to get the commercial channels), then wait until 18th April because that it when the power of the commercials will increase. Should you go down this route, then the aerial should be mounted vertically for best reception of the commercial channels.
| link to this comment |
P.Hollies: I think that by and far the most likely possibility, due to your proximity to the transmitter, is the high signal strength on the BBC multiplex which last week went to full post-switchover power.
The other multiplexes are still on low power. However, at your distance, you shouldn't have an issue picking them up.
The reason for them being unavailable is probably due to the high power BBC multiplex desensitising your receiver. That is, it is "seeing" the very high strength BBC signal and reducing its sensitivity which consequently means that it is not sensitive enough to pick up the other channels.
It's a bit like when you're in a room at night with the light on and you look out the window. Your eyes are desenitised by the light, which is why if you turn off the light, you can see out the window. Unfortunately you can't turn off the light in this case, but you can give your receiver shades in the form of an attenuator.
See here:
Freeview signals: too much of a good thing is bad for you | ukfree.tv - independent free digital TV advice
Get yourself an attenuator to reduce the level of the signals going into your receiver. A 20dB variable one is probably best as it will let you adjust it to best effect.
If you have a set-top aerial, you could try that (until you get an attenuator) as it will pick up less signal, although it may not be perfect. A crude (temporary) way of attenuating the signal is, if one of the aerial connectors is one that screws together is to remove the outer metal (screen) part so that only the centre conductor connects to the socket.
For those channels which you don't have, try manual tuning if your receiver allows:
ITV3 Ch40 (Ch41 from 22nd Feb)
Pick TV Ch44 (no change of channel on 22nd Feb, apart from removal of offset which is irrelevant when tuning)
Yesterday Ch41 (Ch47 from 22nd Feb)
If you loose any channels before 22nd February, don't retune! They haven't changed channel and all you risk doing is loosing them from your receiver's memory which means that you won't know if and when they come back.
| link to this comment |
Chris Panayi: HD services will start at the second stage of switchover on 21st March.
| link to this comment |
Monday 13 February 2012 12:08PM
Adelene: There are a number of possibilities and we have to be mindful that there might be a number of issues.
Firstly, the booster. What is its purpose? Does it provide three outputs, each one feeding a TV?
If it is a variable booster, then try turning it right down.
Have a look at this page:
Freeview signals: too much of a good thing is bad for you | ukfree.tv - independent free digital TV advice
It could be the case that (if the booster is used to split the signal three ways), that there is no need for it now (the signals are stronger after switchover). You might find that a non-powered splitter will work just fine.
Before you go down that route, try feeding the incoming aerial directly to one of the TVs and see if it clears the problem. If it does, then perhaps the problem is too much amplification.
Your son's TV; where a TV or box keeps "forgetting" some channels, it tends to indicate that the memory used to store channels is full and that those it doesn't remember won't fit in the memory. This is often as a result of the set picking up signals from other transmitters as well as the one that is used to view programmes. Because the automatic tuning scan goes from low frequency upwards, it picks up the lowest first. In the case of Tacolneston, it uses high frequencies, so the scan will get to it last. A first suggestion is to run the automatic tuning scan with the aerial unplugged for the first 25% of the scan. If that doesn't work, then we will have to see what other workarounds might be available.