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Old March 31st 18, 07:32 AM posted to
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Default Crystal Palace Issues

On Fri, 30 Mar 2018 22:26:04 +0100, Dave W

On 30/03/2018 14:36, John wrote:
I dutifully retuned, and was shocked to find a load of channels missing! Especially annoying was the loss of BBC News HD and BBC Four HD.

As explained elsewhere, two multiplexes have migrated from their Group A homes to UHF 55 and 56. Given that London has had its channels in Group A for years and years, there must be a very good reason for shoving them outside of Group A: money and technical issues.

I live in a Central London tower block and have my own Group A aerial pointing at Crystal Palace/Croydon at rooftop level and a 70m cable run down to my living room.

I complained to the Digital TV folk. To my surprise, they are sending sub-contractors to have a look to see what can be done.

The obvious thing would be to remove the existing Group A aerial and replace it with a Group W one. However, I worry about its lesser sensitivity at the Group A end. The rooftop is so high (effectively the 22nd floor) that I fear interference from Bluebell Hill and Hannington. Is this something that I ought to fear in the era of DTT? Or could it mean being able to see local news from different areas?

Is an alternative getting a Group C/D aerial and combining it with the existing Group A? Advantages/disadvantages?

It seems as though the beneficiaries of the changes are the ones who have to pay to sort out reception problems like mine. I am surprised that I have heard no complaints from London friends about the loss of channels. Maybe they have not noticed yet or they have Sky or cable or never had a Group A aerial to begin with? I wonder why it was not technically possible to leave those muxes where they were?

I see from my Humax PVR that it sees no signal whatsoever from 55 or 56 from the existing Group A. I am not surprised.

I post this to get advice and receive comments, but also to tell you that if you have been affected by these changes in your area, then so long as you do not have Sky or cable or some other means of getting the full panoply of channels, then it appears that the beneficiaries of these changes have to pay to put people back in the position that they were in to begin with before the changes.


I too have lost channels owing to the abandonment of the sensible
grouped channel system. I don't know why they couldn't have put the new
phone allocation at the top of the UHF band instead of the middle, but
maybe the high channels are useful for fill-in transmitters.

My understanding is that they did exactly this by reallocating the top
part of the TV band for telephony. My understanding is that channels
55 and 56 are in the centre of the new 5G band where there is a gap to
keep the transmitted and received mobile signals apart; and that slice
is temporarily used for broadcasting.

Mark can keep us right if necessary.