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itsrobert6,453 posts since 23 Mar 2001
Granada North West Today
I'm wondering if I may tap into some of the impressive expertise of members with this question.

A couple of years ago or so, various channels shifted around on the Winter Hill transmitter. I have 3 TVs all connected to the same aerial via a signal booster/splitter situated in the loft. Prior to the channel reshuffle, I received everything perfectly on all 3 TVs. Since then, however, I lost reception of BBC News HD (and some other channels, BBC Four HD as well, I think) on my kitchen Samsung TV. However, reception of BBC News HD remains to this day on the other two Sony TVs.

My initial reaction was that the transmission power had been cut and since the kitchen TV is the furthest away from the aerial, the signal had dropped out. But, the problem I have with this theory is that both the signal strength and quality of BBC News HD on the Sony TVs is a rock-solid 100%. There's absolutely no indication of reception issues at the aerial.

The other oddity is that except for the mux that carries BBC News HD, everything else is received perfectly by the kitchen TV with absolutely no dropouts whatsoever. I even plugged one of the Sony TVs into the kitchen aerial wall socket and, to my amazement, BBC News HD was received perfectly with signal quality of a solid 100% and signal strength at 80%.

The only conclusion I can draw is that something changed in the way this mux is broadcast that isn't compatible with my Samsung TV. I'm certain it can't be a reception issue.

Has anyone ever come across anything like this before? Is there anything I can do to resolve this?

Thanks in advance for your help.
Brekkie33,936 posts since 4 Jan 2003
HTV Wales Wales Today
I'm on Winter Hill and as you used to get all the muxes with no issue but for the last year or so it is intermittent not so much on the BBC News HD mux (COM 7) but on the BBC Four HD mux (COM 8 ). In my case I'd say my Samsung probably receives it best.
Stay Home. Protect the NHS. Save Lives.
commseng376 posts since 8 Dec 2016
London London
Does your Samsung TV indicate signal strength and quality on channel 55 (746MHz) which is the Com 7 Mux that has BBC News HD on it?
If you can receive the BBC B Mux - which has all the usual PSB HD channels on, then your Samsung ought to be able to receive the Com 7 mux, as the parameters are almost identical.
The BBC B mux is on channel 54 by way of comparison. It might be worth looking at the comparative levels between these two adjacent channels - is the BBC mux much higher in level that the Com 7 one?
If Com 7 is there, but at low or no quality, then reducing the gain of your amplifier may help.
It might be that your Sony TV can cope better with higher level signals than the Samsung.
All a bit of a guess I'm afraid!
Note that on the 20th Feb, Com 8 will move to channel 56 from Winter Hill, and on the 22nd April there are yet more changes.
Details here https://www.freeview.co.uk/sites/default/files/2019-11/700mhz-clearance-events-granada-region.pdf
Last edited by commseng on 15 February 2020 10:25am
Mr Kite901 posts since 15 Aug 2007
Granada North West Today
Right, so I rescanned my TV, which is on Winter Hill and the BBC A multiplex on CH32 has been loaded into the normal LCN slots, the existing CH50 mux has been relegated to the high numbers. Unfortunately, the CH32 signal is unstable, as is the Liverpool local mux now on Ch21.

Clearly, the aerial isn't up to it and is almost certainly a band C/D. So it'll need replacing. Winter Hill is supposedly going to be Group T but this seems to only be because of Com 7 & Com 8 which are due to disappear anyway. Also, I don't currently have an HD telly so it's irrelevant to me. Is it better to get a Group A aerial or is the Group T better insurance in case the powers that be have other ideas in the future? Is the difference in efficiency in picking up the signals likely to be much different between the two types?

Living in the Wavertree area of Liverpool, I quite likely have the option of using the Storeton transmitter as well. It's nearer to me and has all the same muxes as Winter Hill bar Com 7 & 8. It would be Group A but for the local mux which will be CH43 making Storeton officially Group K. Similar to the previous question, will a K aerial likely perform much different to an A? I'm guessing not but would appreciate the opinion of someone more knowledgeable on the subject. Additionally, Storeton being vertically polarised: does this give it an advantage in terms of minimizing interference from neighbouring transmitters, considering, bar some tiny relays, they're all horizontally polarised?

If you've made it this far, thanks for reading.
Last edited by Mr Kite on 11 March 2020 6:03pm
commseng376 posts since 8 Dec 2016
London London
Have a look at this website to explain the differences between different groups of aerials.
https://www.aerialsandtv.com/knowledge/aerials/tv-aerial-groups-widebands
If you are not bothered about receiving Com 7 or 8, which will be switched off in a few years anyway, then from 22nd April, all the other Winter Hill transmissions are channels 21 to 40 - so if you need better gain, or you want to reject signals on the old TV channels above ch 48, then Group K would be better than Group T or W.
Worse case is that the gain of group K compared to group A is only 3dB down at certain frequencies.
Storeton being vertically polarised would require a different aerial of the same type - channels from there from 22nd April will be 22 - 43, so again Group K is fine.
As for what the future holds - difficult to know, but hopefully it is unlikely that Winter Hill would add channels between 49 - 60 having just moved them all! But if you want to be 100% sure, you ought to install the recommended group T. But the highest channel in future will be 49 - so I think you'd be safe with a K.
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Brekkie33,936 posts since 4 Jan 2003
HTV Wales Wales Today
Was just about to post the same - getting almost daily drop outs compared to a very stable signal previously. Still a joke making the signal for your 48 inch TV unstable in order to watch the content on a 5 inch screen.


Would be better all round just to close the BBC SD mix and make the long overdue switch to HD/T2.
Stay Home. Protect the NHS. Save Lives.
Markymark7,815 posts since 13 Dec 2004
Meridian (North) South Today
Many thanks for the replies. Looks like a Group K is definitely the way to go.

This 5G had better be worth it! Cool


Yes! In fact you don't want anything that efficiently receives 49 and above, because it's possible to overload your receiver with 5G signals using those allocations should a local station be in the same direction as your TV transmitter
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DVB Cornwall9,182 posts since 4 Dec 2003
Westcountry Spotlight
Many thanks for the replies. Looks like a Group K is definitely the way to go.

This 5G had better be worth it! Cool


Yes! In fact you don't want anything that efficiently receives 49 and above, because it's possible to overload your receiver with 5G signals using those allocations should a local station be in the same direction as your TV transmitter


(unless you want to adequately receive the temp COM 7 and COM 8 muxes)
commseng376 posts since 8 Dec 2016
London London
Many thanks for the replies. Looks like a Group K is definitely the way to go.

This 5G had better be worth it! Cool


Yes! In fact you don't want anything that efficiently receives 49 and above, because it's possible to overload your receiver with 5G signals using those allocations should a local station be in the same direction as your TV transmitter


(unless you want to adequately receive the temp COM 7 and COM 8 muxes)

If you read the question he had stated that he wasn't bothered about receiving those two muxes.