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Old August 20th 17, 06:41 PM posted to uk.tech.digital-tv
Woody[_5_]
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Posts: 1,723
Default Query: Reception on Cambs. - Norfolk Border


"fred" wrote in message
...
If you can get it, most people prefer Tacolnestion to get the Anglia
(Norwich) service.

Taclonestion was improved at DSO, part x with new mast and 3dB more
power (relative to most other analog v digital powers). This should
make a few of the relays eg Kings Lynn/Sandringham (that were added
purely to provide Anglia service when Belmont signal was adequate)
superfluous.

Also Belmont tower was reduced in height ISTR.

Someone I know in Stowbridge now a gets a good signal from
Taconeston.



Tacolneston has gone up by 41m, Belmont has dropped by 36m.
Therefore Tacolneston has gone up by 12% but Belmont has dropped by
only about 9% so one would expect the difference in coverage from
Belmont to be much less.

The transmitter power is measured differently analogue v. digital. The
ratio is a factor of 5 or 7dB. Tacolneston was 250KW and is now 100KW
so in common terms the power has indeed gone up by 3dB. However
Belmont was 500KW and is now 150KW so has also had a power increase of
about 1.75dB. (All figures in erp.) In the real world where fade
margins can be as high as 20dB or more these differences are
insignificant.

You may have noticed many caravans have an aerial that looks a bit
like a flying saucer on a stand with a spike out of the top centre.
These aerials were pretty useless on analogue transmission but really
came back to life after DSO and now work surprisingly well. The same
goes for domestic reception, primarily in both cases because (1)
digital TV receivers are (IME) about 20dB more sensitive than analogue
were (you only need around 100uV to get a solid picture on DTTV
against more like 1mV on analogue) and (2) there is forward error
correction on DTTV hence why it works apparently perfectly much closer
the cliff edge or drops over it and stops working for as little as
1-2dB signal strength change (assuming 100% signal quality.)

No, in this instance Belmont is the preferred site even if it doesn't
radiate (IMO the dreadful) Anglia TV. For the record, with a decent
aerial and good siting it is not too difficult to get Tyne-Tees from
Bilsdale even as far south as Cambridge!


--
Woody

harrogate3 at ntlworld dot com