menuMENU    UK Free TV logo Archive (2002-)

 

 

Click to see updates

All posts by Tracey

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

T
Mendip (Somerset, England) Full Freeview transmitter
Saturday 31 October 2020 9:12AM
Glossop

Hi, sorry if this is one of those impossible to answer questions, but here goes. We've recently moved into a different house, in Glossop, SK13 8ED, and are having very occasional reception problems. In decent weather everything is good but with really heavy rain we get blocking and, more rarely, break-up. I remember the previous owners mentioning that the aerial and all cabling were replaced not long before it went up for sale, so it's less than a year old. The aerial would seem to be pointing to Winter Hill (it's definitely not pointing to the local repeater) and from ground level looks solidly mounted. We've tried your re-tuning suggestions and checked the cable joins to the best of our abilities. No difference. A more technical friend suggested that the cable used for the install isn't the best and we could change the internal run for a higher quality one. Within the house the cable that we could swap out is around a 15m run and is marked up as ''RG6/U 19.5dB/100m @860 Mhz''. Do you think there would be any value in changing this section? We could do without the expense of getting someone out to check/swap bits at the moment especially as the problem only rarely occurs. Thanks for any help. Tracey.

link to this comment
T
Full technical details of Freeview
Saturday 31 October 2020 4:34PM

Firstly - apologies for the double post - I was in the Mendip region when I added all this, rather than my area, if someone could delete it from there (I couldn't see a way to remove the original). Now, sorry if this is one of those impossible to answer questions, but here goes. We've recently moved into a different house, in Glossop, SK13 8ED, and are having very occasional reception problems. In decent weather everything is good but with really heavy rain we get blocking and, more rarely, break-up. I remember the previous owners mentioning that the aerial and all cabling were replaced not long before it went up for sale, so it's less than a year old. The aerial would seem to be pointing to Winter Hill (it's definitely not pointing to the local repeater, we get far too many channels) and from ground level looks solidly mounted. We've tried your re-tuning suggestions and checked the cable joins to the best of our abilities. No difference. A more technical friend suggested that the cable used for the install isn't the best and we could change the internal run for a higher quality one. From where it enters the house to the tv is around a 15m run and the cable is marked up as ''RG6/U 19.5dB/100m @860 Mhz''. Do you think there would be any value in changing this section? We could do without the expense of getting someone out to check/swap bits at the moment especially as the problem only rarely occurs. Thanks for any help. Tracey.

link to this comment
T
Full technical details of Freeview
Sunday 1 November 2020 5:56PM

Chris.SE:
Hi Chris, thank you so much for such a comprehensive and clear answer. Your point about the cable makes good sense. As you point out (and typically as I've carried out these tests) we don't normally have any problems - todays light rain hasn't brought any on! The aerial is pointing in the direction you suggested as far as I can tell from ground level using an Android compass (and matches various neighbours directions) with the rods being vertical. One thing I have noticed is that ours seems to have less of those rods than surrounding aerials. There's eight of them with another plate just behind. Then the 2 other panels which stick up at the rear each have 4 elements. Not sure if this is relevant but as I say, the others on our road seem to be longer with more rods. We're high up on a hill and the aerial is chimney mounted so trees and leaves wouldn't seem to be a problem. The signal strengths are as follows;
BBCA/PSB1, Strength 92% Quality 100% Bit Error Level 0 BER
PSB2/D3&4, Strength 90% Quality 100% Bit Error Level 0 BER
PSB3/BBCB HD, Strength 90% Quality 100% Bit Error Level 0 BER
SDN/COM4, Strength 92% Quality 100% Bit Error Level 0 BER
ArqA/COM5, Strength 92% Quality 100% Bit Error Level 0 BER
ArqB/COM6, Strength 86% Quality 100% Bit Error Level 0 BER
COM7, Strength 66% Quality 100% Bit Error Level 0 BER
Local - L-MAN Strength 90% Quality 100% Bit Error Level 0 BER
The displayed frequencies all tied in with those displayed on your Winter Hill page except for the Local one (That's Manchester) which appeared as 498Mhz rather than the advertised 754Mhz (searching on 754 found nothing) and PSB3 displayed as 586Mhz rather than 585.8Mhz (maybe my Samsung rounds up?). I'm guessing here, and ready to be shot down, but Is this looking like the aerial itself isn't quite up to the job when really tested? Anyway - I'll stop rambling and hope these numbers indicate something to you (and I'm surprised how much I've enjoyed figuring out how to gather them!). Thanks again for the help.
Tracey

link to this comment
T
Full technical details of Freeview
Tuesday 3 November 2020 3:25PM

Chris.SE:
Again, not sure if it makes any difference but I've also noticed that apart from the neighbours having more of the horizontal elements, each of their rods have a squashed 'x' profile, as if made from 2 pieces of metal at a slight angle to each other, whilst ours are a straight single rod?

link to this comment
T
Full technical details of Freeview
Wednesday 4 November 2020 8:04AM

Chris.SE:
Apologies Chris, no idea why I said Vertical, they're single bar horizontal elements (I must have re-read my post 10 times before I hit send and never spotted that one)! The houses around us are at similar heights and their 'x' elements are wider than taller, so horizontal too, and yes we have a clear uninterrupted view in the Winter Hill direction (although the mast itself isn't visible from any view point I can access, but I guess at that distance it's to be expected).
The G-MAN/GI multiplex on C27 does indeed appear, with signal strength 38%, quality 100%, error 0% (that's with this morning's fairly good weather).
Your frequency explanation made excellent sense, thank you, and I've re-checked my results against your values, and apart from the rounding up my set does, they're all in agreement. Interestingly, my TV has a 'Signal History' menu which 'displays the Channel numbers that were saved when the signal strength was weak'. I've manually re-scanned some of these but haven't found any increase on the 90%'s I was seeing before.
I hope I've answered your points without 'flipping' the information this time! I can't help but wonder why the fitter would use this aerial when from his vantage point he would see at least 7 other aerials (that's just the other side of the road, viewable from my lounge) that have more elements, and in some cases the 'x' type as well. His cabling along the front of the house is very neat, suggesting he takes pride in the finished appearance of his work, so why choose what would seem to be a 'marginal' aerial? (rant over).
Thanks again for your invaluable assistance and apologies for the red herring!

link to this comment
T
Full technical details of Freeview
Thursday 5 November 2020 6:57AM

Chris.SE:
Thanks again Chris. I'll question the previous owner a little more on their choice of installer and see if they have any paperwork to hand. No, unfortunately I don't have any strength and quality figures from the past when reception was poor, the relevant TV menus hadn't been found at that stage. Interesting read on the tropospheric ducting (an interesting looking website in general - I shall read further). As you suggest, I need to wait now for the weather to re-produce the problem and gather more data then. This being Glossop, that shouldn't be far away. I'll report back when I have further information. Thank you for the help, it's been most interesting working through this with your aid.
Tracey.

link to this comment