907
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| posted on 13/4/11 at 07:08 AM |
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TV Aerial Signal Meter
Hi All.
My telly picture occasionally breaks up and goes pixelated, just for a split second, then back to normal.
Some nights are worse than others. Sometimes it flashes up "weak signal."
(Telly is a 32" Samsung, through a Sagem digi hard drive. Sound through a HiFi Sherwood amp and speakers.)
I can't believe it is a weak signal as I can see the transmitter from my house. (Sudbury)
The aerial is mounted on a roof cross brace in the loft, and when I fitted it I just looked out
of the bedroom window and guessed the angle, climbed into the loft and set it where I thought.
I see that on eBay you can buy a cheap signal meter. link, eBay Item
Are they of any use?
Anyone used one?
I'm not very techy minded with these sort of things. 
Cheers,
Paul G
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westf27
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| posted on 13/4/11 at 07:51 AM |
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signal meter will allow accurate alignment to maximise signal.Any tree branches,obstructions and passing low flying aircraft will break up signal.Roof
tiles will knock the signal down.Have you got a digi aerial and booster.The aim is for the best quality signal and boost if required.A variable signal
booster is best otherwise you may get too much signal
555
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Daddylonglegs
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| posted on 13/4/11 at 07:57 AM |
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When I set ours up, I used a small portable in the loft, chose the weakest channel I could find (signal indication on the digi-box) and tweaked the
aerial to get the best level on that channel. Everything else was then fine.
HTH
It looks like the Midget is winning at the moment......
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deezee
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| posted on 13/4/11 at 08:29 AM |
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Fitting an aerial in a loft is always going to reduce your signal quite a lot. I'd say if an external aerial isn't an option, then a
digital signal booster should be the next on the list. You can get one for around £15 from the likes of Maplin.
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wilkingj
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| posted on 13/4/11 at 09:04 AM |
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You are using a Wide Band Aerial? (Now called a digital aerial in the trade)
If you are still using an old aerial, it may not be suitable unless you live close to the transmitter.
Aligning the aerial is good so you get the maximum signal you can. However the new freeview channels (well the transponders) are set across the whole
TV band. Old analogue aerials were cut to size for a certain section of the band (and colour coded red/black green etc for the various areas).
If you havent got a new wideband / digital antenna, and you can not improve the signal strength by realignment, then I suggest two courses of
action.
1. Move the existing antenna OUTSIDE the house. As this will increase the signal recieved as there is no roof tiles attenuating the signal.
2. If that still does not help, then buy a new antenna, and make sure its a wideband / digital one. The try inside the loft, and again if not put it
outside.
As an aside, How old is the co-axial cable? If its more than 10-15 years old, I would replace it. The old ones are more lossy than the new ones (old
ones can have a solid dielectric in as the middle insulator, rather than the newer Airspaced (sectionalised) cable which is better.
I would replace the cable if its very old at the same time. Its only a small cost, and completes the job properly.
If your signal is marginal now... Wait until winter gets here with heavy rain and falling snow. You could (and ONLY Could) lose your picture all
together.
Dont go to somewhere like Maplins as they charge the earth. I watched a chap spend £104 on an oversized antenna, a bit of cable, and a handfull of
clips. Daylight robery IMHO.
Find your local TV antenna man and buy from Him (if you trust him). I use Martin Gibb on Michams Roundabout Corner (Chesterton Road) in Cambridge, top
bloke with good knowlege.
Mine cost me £14 for then antenna, fortunately the brackets and pole existed.
Which way does youe aerial point N/East, S/East or East? I'll pop over and give you a hand if you want.
Dont go wasting your money on a Signal Level meter. I can align it with my Laptop and Funcube Dongle!
Paul... Give me a call one evening and I will talk you through it. The above is for others who might find it interesting or need the info.
Cheers
Regards
Geoff.
1. The point of a journey is not to arrive.
2. Never take life seriously. Nobody gets out alive anyway.
Best Regards
Geoff
http://www.v8viento.co.uk
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Humbug
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| posted on 13/4/11 at 09:38 AM |
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If the aerial is ali, you could try polishing it per the car to improve reception 
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Humbug
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| posted on 13/4/11 at 09:44 AM |
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Lucky you who can get digital TV (though aerial) ... in the depths of Kent we won't get it until next year. At the moment I am using a Humax
Freesat box, so it won't make a lot of difference in practice
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907
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| posted on 13/4/11 at 03:57 PM |
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quote:
Originally posted by Humbug
If the aerial is ali, you could try polishing it per the car to improve reception
Do you think I could park the car in the loft Humbug?
Many thanks for all the replies.
Geoff has phoned me and the first thing to try is much what Daddylonglegs did.
I'll have a go and report back.
Cheers All.
Paul G
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wilkingj
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| posted on 13/4/11 at 07:49 PM |
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Just to set the Scene... Paul is 8 mile fom the Transmitter, and shoudl get a perfect signal with a wet finger stuck in the antenna socket!
He can actually see the TV transmitter mast, well all but the lowe 40ft of it.
He has a few things to try out to ascertain where the problem is. When he has done those, we will see what needs to be done to resolve it. ie check
connections, no strands of the braid of the co-ax touching the inner. Continuity of the cable from the wall socket, etc etc. Oh and trying the
portable antenna in the main TV etc etc.
If that doesnt cure it, I'll pop over with a few bits and bobs and sort it.
It could even be too much signal swamping the reciever... ie it could be a few things!.
Still.... we will get to the bottom of it.
Failing that I can give him a design for an antenna and he can make that up and see how it goes!
Thanks for the suggestions.
Geoff
1. The point of a journey is not to arrive.
2. Never take life seriously. Nobody gets out alive anyway.
Best Regards
Geoff
http://www.v8viento.co.uk
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David Jenkins
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| posted on 13/4/11 at 07:58 PM |
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I use the same transmitter (Sudbury) but I'm a bit further away... about 20 miles or so.
It's worth noting that this transmitter is soon to go 100% digital (June?) and they are working on it at regular intervals. We get bad picture
breakup at odd times, e.g. early Sunday morning, or very late at night. I wonder if they're playing with stuff?
Also, the ITV channels are especially bad from Sudbury, and also in other places I believe. Allegedly each broadcaster gets as much bandwidth as
they're prepared to pay for - BBC buy enough to transmit their programmes properly, while the ITV ones cram as many channels into the available
space as they can get away with. We usually find that if one ITV channel is bad, they will all be bad. Sometime we lose all the ITV bunch.
Of course, this may all be a load of foetid dingos' kidneys, but it does me good to have something to whinge about, even if it is wrong! 
Thank heavens for Freesat...
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britishtrident
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| posted on 13/4/11 at 08:07 PM |
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Loft aeriels are prone to inteference reflected signals from inside the loft from objects like the water tank ----- with digital a clean signal
inteference free signal is as important as signal strength.
[I] “ What use our work, Bennet, if we cannot care for those we love? .”
― From BBC TV/Amazon's Ripper Street.
[/I]
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wilkingj
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| posted on 13/4/11 at 08:38 PM |
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The Sudbury Transmitter is relatively low powered at 1.2Kw, as compared to Sandy Heath 1Mw (yes a MEGA Watt) for the analogue channels and 50Kw for
the digital channels.
Also there is an offending transmitter in Belgium transmitting on the same channels, and this can be picked up if you live to the north east of the
Sudbury transmitter. ie pointing at Sudbury and Belgium is in the same direction but somewhat distant! This will affect people when there is a high
pressure weather system over the area. However, this would only affect two channels, ITV and Ch4 (I think - would need to re-check the frequencies).
This is going to change at some point as well, so wont be a problem forever.
I have a lot of experience with antennas, namely making, installing, and using therof.
As an active Radio Ham of over 30 years, I think I can sort it out for Paul. There are a few things for him to try out, then if that fails, he will
get a visit!
When you look at the transmitter power outputs... I am glad I dont get their electricity bill. I wonder how quick the TV companies will recoup the new
equipment costs by the imense saving in electricity. Also its greener with its lower carbon footprint... But Money is probably the real driver!
Enough of the geek stuff from me!... Its time for beddies!
Cheers all.
Geoff
1. The point of a journey is not to arrive.
2. Never take life seriously. Nobody gets out alive anyway.
Best Regards
Geoff
http://www.v8viento.co.uk
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