Do I need a new aerial

[mpooley]

I live in west Norfolk near downham market.

I had a loft aerial installed a few years ago and our freeview reception was pretty good.
When the UK changed to all digital I thought it would get even better.
It has got worse instead!

our best transmitter is 'Sandy Heath' and I have looked on the coverage checker and noticed the Aerial group before changeover was E H
and it changed to A H, W H.

does this mean I need to replace the aerial?

I can't ask the original fitter as I can't remember who it was and we have lost the paperwork.

thanks

Mike

 

[Sam Gangee]

Sandy Heath requires a "wideband" aerial. However, the usual so-called "high-gain Yagi wideband" aerial is really not suitable because Sandy Heath uses 21 - 27 as well as higher ones. A wideband Yagi generally has a much lower gain in the lower channels.

Therefore I would recommend the Vision "Focus" V10-040 log-periodic aerial. This is a true "wideband" aerial and performs well outdoors and in the loft. (I say this from personal experience, as I've installed a few for friends.)

See http://www.satcure.co.uk/tech/best_aerial.htm

Bear in mind that good cable is essential for reliable digital reception and, if you can't change all of your existing cable, change as much of it as you can. Use good double-screened coaxial cable such as WF100.

However, one thought crosses my mind. The main change at "switchover" was that the transmissions increased in power. So your problem might simply be caused by too strong a signal. In this case, an attenuator would probably be all you need. Try a variable attenuator of about 18dB. If that makes no difference, add another 18dB fixed attenuator.

Alternatively, if you are using a masthead amplifier, simply remove it.

(This is all guesswork. If you need more certainty, tell us your postcode and what aerial you have - or a link to a photo of it - plus details of how it's connected to the Television(s).)

 

[mpooley]

Thanks mate
I will try to get that done this week and see how it goes.

thanks again

Mike

 

[daxi]

What is happening to your reception & when?? Is it an all the time issue, or an every so often issue?? Does it happen at certain times, or at any time...When it happens is it over a long period or a short period..???
My initial thoughts are...
Has anything been built close to you & in between you & the transmitter?? Anything like a large (Tall,) building?? something made of metal??? Has a tree grown in between your antenna & the transmitter, as moisture on a ever green could easily give you all year round issues when it was moist.
One of the problems with digital is that it really needs a spectrum analyser to do the job that your eyes did on analogue.
Also don't forget poor weather is not a digital signals best friend, as digital is not as robust as analogue, due to the fact that it is either readable or no signal at all. Whilst with analogue it gently degraded through poor reception to a point where the signal became unreadable.

 

[mpooley]

Hi
Nothing has changed and it seems pretty constant. The channels that work are fine but the channels that break up, always seem bad.

 

[mpooley]

Actually I have found out that the TV is recieving OK - we don't usually watch straight TV we watch using the humax.
I never checked I'm an idiot!

I swapped tv Aerial leads(I have four down from the loft) and it was the same.
So it looks like it's a humax problem

not sure what to do now though.

 

[daxi]

Before you blame the Humax, check the patch leads, thats the leads that link the TV & Humax.
It possibly is not them, but, they are the cheapest & simplest place to start.

 

[Sam Gangee]

If you determine that the Humax itself is at fault, it's likely to be capacitor failure. This is fairly easy to fix with a capacitor kit, assuming you can solder.

 

[mpooley]

Thanks all.
I was so fixated that it happened at the time of the digital switchover that I never looked for the simpler things
It turns out it was the patch leads !

thanks again

 

[Sam Gangee]

Nice one, daxi. It's easy to assume that the obvious has already been checked!