[Gllug] [OT] TFT displays

[Chris Bell]

On Sat 24 Sep, M.Blackmore wrote:
> 
> On Sat, 2005-09-24 at 21:49 +0100, Tethys wrote:
> 
> > I get completely the opposite. I'm also in a poor reception area.
> > Analogue signals mostly work OK, and degrade nicely when they don't
> > (a bit of snow here and there, slightly fuzzy sound occasionally).
> > Digital signals on the other hand are full of glitches, and have
> > terrible degredation characteristics.
> 
> Same here out in the wilds of Charlbury - edge of the Cotswolds about
> 11-12 miles out of Oxford. Analogue mostly OK with a high gain amplified
> antennae on top of a 16' pole!
> 
> Surely they will be filling in a few smaller transmitters (or boosting
> power significantly, Channel 5 won't work at all in digital or analogue)
> for those areas which are a bit shadowed ... surely?
> 
> They can't just chop off the analogue leaving large chunks of the
> country without a proper reception (unless they expect us all to go
> satellite. I'm now wishing I hadn't spent the money on the fancy aerial
> and had just gone for the basic Sky freeview box...).
> 
> Even when we were in London (north Croydon) we got a bit of bad
> reception at times due to our position at the edge of the downslope of
> the hill which had the transmitter bang on top of it! I always was
> amazed at that. Perhaps we were "too close"??

   It is possible that you are feeding too much signal into the head amp,
causing waveform distortion and intermodulation problems. I have an 18
element aerial on top of a scaffold tube, followed by a distribution
amplifier. The signal is poor because of multipaths, but not very low level
(except for Ch5 analogue). I had to use a directional aerial to reduce
multipaths, then attenuate the input to the amplifier to avoid overloading.

   There was a well known problem around Crystal Palace because the aerial
was too well designed, and it did miss those underneath the mast. That
should have been fixed some years ago when a small reflector was fixed near
the top. The problem we had when working at Crystal Palace was RF pickup on
everything.

-- 
Chris Bell

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