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All posts by Stephen

Below are all of Stephen's postings, with the most recent are at the bottom of the page.

S
Mendip (Somerset, England) Full Freeview transmitter
Monday 28 November 2016 10:01AM
Bristol

Over the weekend 26,27 Nov 2016 we have had none of the channels on com7 (eg BBC4 HD, BBC news HD). Checking the signal strength it is given as 0% - absolutely nothing. In the past values below 25% in heavy rain have given occasional blocky pictures. All other channels are fine with signal strengths in the 30-50% range so the roof aerial is still working OK. The web site says that there are no transmitter problems. Re-tuning in case com7 has moved frequency finds nothing. Our postcode is BS6 7JR.

Any ideas?

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MikeB

many thanks for your response. You seem to be saying that my roof aerial signal is much weaker than
expected. That is possible as it is over a decade old. Unfortunately access requires scaffolding which will have to wait until the building is redecorated.

Last year we lost the same channels plus a few more when one of the many local (100m away)
phone masts was ungraded. They explained that as the phone signal overloading the receiver causing it to
reduce the DTV signal so far that it could not be used (10-15% signal shown). The fix was a filter in the aerial wire. My understanding was that the filter would remove all the allocated phone frequencies. Could it be that even more frequencies are now in use and the problem has been repeated?

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Chris.SE:
many thanks for your lengthy reply. By the time I got around to this last night (Monday) BBC4 HD and related had all re-appeared without any cable changes. The signal strength was 29%, what I have seen in the past for com7. The signal quality for com7 and all the other channels from Mendip is given as 100% despite signal strengths of 30-60% depending on channel.

The aerial points close to due south, at Mendip. The aerial rods are horizontal, but from memory I could not say how many there are. The aerial down-lead is about 20metres long with the filter a 1m lead away from the DTV. The weaker signal during heavy rain only lasts as long as the rain and does not continue for a day or two afterwards.

With things working again I am happy for now. Not really knowing the cause of the problem is not ideal. The jump from 29% to 0% signal strength seemed rather binary rather than a slight degradation.
I note that my signal strength seems weaker than expected at this distance and on a hill. When we next redecorate I will have the aerial and downlead inspected and replaced if necessary with the view that a stronger signal should help in the future.

Many thanks, Stephen

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Scotty:

after working all last week Mendip com7 cut out again for me Sat 3rd to Mon 5th, and returned at its normal strength on Tuesday. A similar pattern two weekends in a row. Do you see something similar?

If not perhaps it is local interference as Chris suggested, maybe related to several neighbors who work away in the week.

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