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Old 09-11-2007, 11:34
Leggie
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I live in Farnborough, Hants and have a Sony KDL46X2000 LCD TV and a Sony RDR-HXD870B DVD Recorder BOTH with built in Digital Freeview.

I am getting some Freeview channels but not that many. (12 or so including radio).

However the EPG on the DVD recorder is showing some program details from many channels that I cannot receive. It dosn't show all the possible channels as many fields are left blank.

If I understand it correctly this page http://www.wolfbane.com/cgi-bin/tvd.exe with an OS Grid Ref of SU843552 suggests that all three digital transmitters could benefit from an amplified extra high gain aerial?

This site http://www.digitaluk.co.uk/postcodec...ed/gu140qq/1/1 suggests that by using Crystal PalaceTransmitter 43 Good and 12 variable channels could be received.

Do you think its possible to pick up from Crystal Palace. (I don't actually know which transmitter I use at the moment anyway.

Does the fact that I can see Program details within the EPG indicate that I could receive sound and picture with a better antenna.

Any help or suggestions are welcome. Thanks

Last edited by Leggie : 09-11-2007 at 11:47. Reason: Inaacuracies and bad web links
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Old 09-11-2007, 12:11
soulboy77
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All the transmitters listed broadcast the full set of muxes so if you can get a decent signal from anyone of them you will have all the channels. Wolfbane suggests that from a distance versus power point of view, Hannington would be your best bet. The aerial needs to be horizontally polarised and either group B or Wideband.

I would add that you may also need a masthead amplifier to get the signal up to an acceptable level.
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Old 09-11-2007, 12:35
Leggie
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Wolfbane suggests that from a distance versus power point of view, Hannington would be your best bet.
Thanks for prompt reply. When I enter Hannington in www.digitaluk.co.uk checker it indicates no channels are likely to be available to me at present but 55 Strong Channels in 2012.

However as I said before entering Crystal Palace suggests a lot more channels would be available to me now. Do the stats indicate what chance I would have of receiving from CP?
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Old 09-11-2007, 12:43
chrisjr
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Hannington is not Group B, despite what Wolfbane says. it is Group E. Also in Farnborough it may not be the best choice either.

Hannington has a big null in it's coverage to the east to avoid channel clashes with Guildford. From what others have posted on DS in the past this seems to make reception tricky in that part of the world from Hannington.

A quick and easy check to determine transmitter is to see what BBC local news you get (assuming BBC1 is one of the channels you can get). If it's South Today then you are getting Hannington. Anything else and it's CP or Guildford (Guildford requires a vertically polorised aerial so that helps distiguish it from the other two). Similarly ITV do Thames Valley news from Hannington.

Oh and Wolfbane suggests I too need an extra high gain amplified aerial. Though I actually have a rather old and who knows what condition (but certainly not "extra high gain") aerial, crappy old coax with a joint in the middle that has long since lost any protection it had from the elements and it all works perfectly Strange world these digits inhabit
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Old 09-11-2007, 12:52
Ray Cathode
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You can't beat local knowledge for TV reception.
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Old 10-11-2007, 11:22
Leggie
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in Farnborough it may not be the best choice either.

reception tricky in that part of the world from Hannington.

If it's South Today then you are getting Hannington.
On an old analogue TV that I have when I select Teletext BBC1 shows as BBC South and ITV shows as ITV South. I guess this means Hannington?

I can also receive "snowy" Carlton when my normal ITV is Meridian.

On looking at Neighbours roofs there seems to be antennas pointing in all different directions and some seem to have two in different directions.

Any ideas as to whether I can get Crystal Palace here to a decent standard?

Oh well, I guess I take the plunge and find a decent installer to talk to.

Thanks for all your input everybody!
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Old 10-11-2007, 12:32
albertd
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On an old analogue TV that I have when I select Teletext BBC1 shows as BBC South and ITV shows as ITV South. I guess this means Hannington?
You should be able to confirm this by selecting teletext on the analogue ITV and wait for P100 to come up. Then press the reveal button. This should give a 3 letter transmitter ident on the right hand side of the main title bar. I don't know what Hannington would be (probably HAN) but Crystal Palace shows CRY. Not sure if relays have their own ident or that of the parent transmitter.
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Old 10-11-2007, 14:11
Leggie
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Thanks.

Its shows the letters ROW.

Any ideas?
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Old 10-11-2007, 14:49
Leggie
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Looks like it might be Rowridge? Wolfblane says "extreme outer fringe" and Crystal Palace, Hannington and Guildford are all nearer anyway.

Does all this support the idea that I should get a new antenna and get it pointed to a better transmitter or have I missed the point somewhere?

Thanks again in advance
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Old 10-11-2007, 15:15
albertd
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Looks like it might be Rowridge?
Sounds possible. To confirm it, if you are able to look up the list of tuned analogue channels with their UHF Channel numbers (maybe via the Analogue Setup Menu - but don't change anything) the relevant numbers for Rowridge and Hannington are:

Rowridge 31, 24, 27, 21

Hannington 39, 45, 42, 66

for BBC1, BBC2, ITV1, Ch4 respectively.

If you are getting a different set altogether, report back here with the numbers and we will try and work out what you are getting.
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Old 10-11-2007, 15:20
Mr. X
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I live in Farnborough, Hants and have a Sony KDL46X2000 LCD TV and a Sony RDR-HXD870B DVD Recorder BOTH with built in Digital Freeview.

I am getting some Freeview channels but not that many. (12 or so including radio).

However the EPG on the DVD recorder is showing some program details from many channels that I cannot receive. It dosn't show all the possible channels as many fields are left blank.

If I understand it correctly this page http://www.wolfbane.com/cgi-bin/tvd.exe with an OS Grid Ref of SU843552 suggests that all three digital transmitters could benefit from an amplified extra high gain aerial?

This site http://www.digitaluk.co.uk/postcodec...ed/gu140qq/1/1 suggests that by using Crystal PalaceTransmitter 43 Good and 12 variable channels could be received.

Do you think its possible to pick up from Crystal Palace. (I don't actually know which transmitter I use at the moment anyway.

Does the fact that I can see Program details within the EPG indicate that I could receive sound and picture with a better antenna.

Any help or suggestions are welcome. Thanks
Ignore the Wolfbane site. It says I should have an "amplified extra high gain" antenna for Winter Hill analogue, the "Tower of Power" everyone here has always got a clear picture from using rubbish small rooftop aerials. I've also watched Freeview in a place where that site says "nothing within DX range" on analogue.
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Old 10-11-2007, 16:19
Leggie
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ThanksI

Its Hannington then.

Any thoughts on repositioning to Crystal Palace?
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Old 11-11-2007, 14:44
Pop Roberts
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Both Hannington and Midhurst ident as "ROW"on analogue teletext and are a lot closer than Rowridge.

Your current options for Freeview (due to the null in the Hannington pattern as Chrisjr points out) is either Crystal Palace or Midhurst. I can get reasonable DTT signals from both here in Frimley. It will depend on whereabouts in Farnborough you are, with your height and any local obstructions, as to the sort of reception you will get. The only real way is to try it out. For Crystal Palace you will be better off with a Group A aerial. Your current aerial (assuming you are using Hannington) should be ok for Midhurst.

Very rough directions for you to see where the local aerials are pointing are: east for Crystal Palace, west for Hannington and south for Midhurst.

Good luck,

Pop

Edit - just looked at the paths between you and the transmitters using Megalithia Terrian, and it would seem Crystal Palace would be the slightly better option.

Last edited by Pop Roberts : 11-11-2007 at 14:52. Reason: Additional info
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Old 11-11-2007, 16:20
reslfj
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.....
Edit - just looked at the paths between you and the transmitters using Megalithia Terrian, and it would seem Crystal Palace would be the slightly better option.
Try to download Google Earth

Find the transmitter mast and your house and use the ruler to draw a line form your house to the mast.

Zoom in on your house and print the pictures.

Eksamples:
Google pic 1

Goggle zoom

Lars
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Old 11-11-2007, 19:09
pjb007
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When I was at uni in Chester the Wolfbane website suggested a amplified extra high gain aerial. However as no outdoor aerial was available I managed on an indoor one. Picture not 100% but still watchable.

So that site may not be 100% reliable.
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Old 11-11-2007, 19:31
Orry Verducci
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I think Wolfbane works off just distance from the mast, rather than actual signal predictions, hence the inaccuracies. I haven't seen any aerials on the market nowadays that use the names listed on the Wolfbane site, which makes things slightly confusing. Amplified Extra High Gain is comparable to CAI Standard 2 aerials (I think, taking into account the aerials in use in this area). Generally, if the aerial has a gain of at least 10dBi, you should be fine. Most on the market have a gain of around 12-14dBi.
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Old 11-11-2007, 20:01
Nigel Goodwin
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I think Wolfbane works off just distance from the mast, rather than actual signal predictions, hence the inaccuracies.
Wolfbane is like all the prediction sites, it's just a crude geographic estimate - it has little relation to actual performance.

But there's no way to do it accurately, so it's probably the best you can hope for?.
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Old 10-12-2007, 11:08
fmfm20j
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Last Friday we purchased a 40W3000 Sony LCD TV and I was really surprised to find that it made a reasonable effort to pick up freeview using the ancient and very basic roof mounted aerial (pointing toward Hannington).

In reading your thread it seems like we would benefit from a better aerial as the freeview only picks up a few BBC stations reliably and even these pixelate every now and again.

We have a Virgin Media service already in place and I have found that the new TV exposes the compression that the cable services use in their broadcasts. The freeview does seem to be quite a bit better (on the BBC at least).

I contacted the place where I bought the TV with a view to getting a decent aerial company to do a site survey and possibly upgrade what we have. It seems a shame to have a decent TV and to then send in a signal that is compressed (assuming that Freeview would, on balance be better).

Given that we are in Frimley (opposite Johnsons Wax), for those who have knowledge of the area, do you think that the 120 to 180 (+VAT) that we have been given as an indicative cost to upgrade the aerial will be money well spent? Also, is this sort of figure for a standard aerial replacement or a wideband unit (180) about the going rate for this area ?

Many thanks for your help.

Ian
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Old 10-12-2007, 13:57
Ray Cathode
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Make sure you get a guarantee of a good signal on your TV from all muxes and analogues on one transmitter. If the company has a spectrum analyser and will give you a print out of your reception so much the better. Haven't heard of anyone doing this as they cost thousands.
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Old 10-12-2007, 14:36
fmfm20j
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Thanks Ray,

my background is in mixed signal micro electronics rather than RF communications electronics.

Please could you explain a little more or point me toward an explanation of what is meant by

"muxes and analogues". Sorry to appear totally thick.

Thanks

Ian
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Old 10-12-2007, 14:47
Ray Cathode
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I thought Marconi did it all? There are six digital TV multiplexes (muxes) and four or five analogue TV stations each broadcast on a different UHF channel. With aerial installations it is common to end up with reception on one channel worse than the others. This can cause reception problems in bad weather for example.
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Old 10-12-2007, 15:26
fmfm20j
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Thanks for the explanation Ray. I dug a little with google and that aspect now makes a lot more sense.

If I understand correctly, on the basis that I'm on the fringe of reception from Hannington (where my aerial currently points), I'm picking up something on the BBC stations because the transmitter is running maximum power on Mux 1. With a better aerial I might get even better signals on Mux 1 and mux B, might get something on mux c and d but may always struggle with 2 and A.

So, to check for the quality of the installation, aside from checking a few channels on a strong mux, I should look through a number of channels on 2 and A to see if a) I can even get them b) if the picture breaks up frequently.

I think I now see your point of the spectrum analyser: if it was able to monitor the signals, I should be able to pick each one out of the noise floor if I look on the end of the UHF cable that plugs into the back of my TV.
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Old 10-12-2007, 15:55
chrisjr
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Part of the problem with where you live is that for the time being Hannington has a big null in it's transmission pattern to the north and east. This is to avoid channel clashes with the Guildford transmitter.

So you cannot base reception on the published power levels from Hannington since the digital antennas are only on two sides of the mast pointing roughly west and south. If you have your anorak to hand you can see them here, the white rectangular things just below the big white cylinder right at the top of the mast (the analogue antenna)

It does affect reception to the north east to where I am as well, though from other posts on DS perhaps not a badly as your direction. Certainly in the very early days of digital I could not get a subscription to On-Digital or ITV Digital because the post code checkers they issued said digital was impossible where I am. I had been enjoying perfect Freeview reception for a couple of years before the Freeview etc. post code checkers caught up
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Old 10-12-2007, 19:29
Pop Roberts
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Ian,

Please see my comments in post #13 regarding reception in Frimley. I'm not too far from you, but I'm on top of the hill just behind you in the direction of Crystal Palace. As chrisjr points out, Hannington will not be suitable until DSO because of the null in the radiation pattern. The other options are Crystal Palace or Midhurst. Make sure the aerial fitter you employ does a full survey with signal analyser to choose the best transmitter (and appropriate aerial group) for your particular location. Assuming you are right down by Johnson's Wax, Paddock Hill right behind you may just be a hill too far for the Crystal Palace signal, but without measuring it there's no real way to find out.

Good luck,

Pop
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Old 10-12-2007, 20:00
fmfm20j
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Thanks for the info Pop. Actually, it was a google search with Frimley and Freeview that took me to this forum initially!

Virtually all of the aerials in this part of Frimley seem to point towards Hannington. All of them are the basic 18 (?) element design. NTL have done reasonably well here by converting many to cable (including us). Hence the basic aerials left as an ornament on the roof tops.

The chap in the shop on London Road told me some time ago that it's quite difficult to pick up anything from Crystal Palace in this particular spot.

The company that I have chosen comes recommended from the Sony Centre in Camberley. They are a small company based locally and are supposed to be very experienced. Setting up an aerial in this area is clearly more than twisting an aerial until a picture appears. I'm somewhat in their hands but the great thing is that with every post I'm learning more and more. With luck they will offer me decent advice and allow me to make an informed decision.

If all else fails, I still have the signal from the Virgin Media box. It would be just great if I could rely upon Freeview though because the picture seems to be so much better.

Thanks

Ian
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