Mendip Off-Air

MikeSh said:
I realise that, but things can change or loosen. The recent hot weather might have heat cycled a marginally tight fixing.
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Everything looks present, intact, and pointing in the right direction (from ground level inspection).

MikeSh said:
That sounds like trees perhaps. The buggers do tend to grow :dunno:
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Looking across the rooftops from upstairs, that is a possibility with nothing I could do other than get a taller pole! :cry:

The alternative is to switch to Wenvoe :frantic:
 
Black Hole said:
Looking across the rooftops from upstairs, that is a possibility with nothing I could do other than get a taller pole! :cry:
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Years ago, in the days of analogue, I bought a new build flat in the middle of a block - the two storey ones that look like terraced houses. About 75yds away, between me and Crystal Palace (about 25 miles away) there was a big Oak tree.

The people on each side of of us had the usual contract aerials on a standard bracket and pole for each flat, but the aerial installer had a struggle with ours. In the end me and the person in the flat above shared a big high gain aerial on a massive pole via an amplifier in the loft (fed from upstair's lighting circuit).
It wasn't cheap. :(
 
My UHF30 seems to have died, I had M*A*S*H on until a little while ago, now there's no signal.

I think that's a low-power local mux.
 
It's not CCI is it BH? I frequently have that which usually wipes out one or more MPXs.
I have two aerials that I can swap between and switching them usually, but not always, fixes it.
 
Maybe, perhaps that's the answer to all my problems with this high pressure about, but I also notice DAB and FM are pretty bad while I'm out in the car.
 
My SDN/COM4 (RF ch. 48 from Mendip) was not working when I returned after being away in the furnace last week.
Strength was varying 0/10/24 and quality 0/10, which meant nothing decoded.
It's since come back with strength 27 (and quality 100), but is well down on the rest which are 48-57 or so, and even the local mux. is 36.
Until COM7 closed, strength on that was OK on ch. 55, so not just loss of high frequencies.
The aerial is a log anyway, so shouldn't be too much frequency selective sensitivity. Not sure where this apparent notch is coming from... or maybe it's CCI.
Anyone else got any observations?
 
Reception location, approx?

Signal level of 48-57 isn't imho sufficient for a -T2 (or at least not my one) {that level gave me occasional breakup of channels ex Tacolneston when I was in Hemsby with my caravan a few weeks ago. Trees and lack of line of sight won't have helped. 60-70% is usually ok, if memory serves me.
I'm wondering if a log periodic (which one there are many?) is sufficient for your location (external/loft/?)?

The weather currently (Sunday 24th) isn't particularly conducive to enhanced propagation (and hence CCI) unless your predictions are poor on the detailed view of the Freeview tool.
Around the 18th July BBC reception advice confirmed it was affecting people https://www.bbc.co.uk/reception/work-warning/news/waw-high-pressure at that time and a few days before/after no doubt.

Local muxes are more robustly coded (with lower data payload as a result) so lower S level works for them.
 
Caldbeck transmitter:

Ch 30 strength 44, quality 50-70%
Ch 33 strength 26 quality 100%

Have been giving problems for a couple of weeks now, in and out reception on radio channels particularly. (Having resorted to Freeview as Humax internet radio has gone tits up).

Anyone have up to date site for Caldbeck channels available as UK Free tv is way out of date?
 
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Rodders53 said:
Reception location, approx?
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North Somerset.
Signal level of 48-57 isn't imho sufficient for a -T2 (or at least not my one)
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It's fine down to about 30, IME.
Trees and lack of line of sight won't have helped.
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I am partially obstructed by a ridge 2-3 miles away and the consequent diffraction loss, but it's been OK for the last 14 years (apart from this incident - post #5).
In the analogue days I was on a relay, but wanted digital 2-3 years before DSO hence the change, and in those days the powers were lower than they are now. The relay is of course no use for the COMs.
I'm wondering if a log periodic (which one there are many?) is sufficient for your location (external/loft/?)?
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I've no idea of the make. It is external and sufficient. If it was in the loft I'd be all over it, but a) aerials should generally be outside and b) it's right at the top of the ridge where I have no desire to go, even if I had a ladder long enough, which I don't.
The weather currently (Sunday 24th) isn't particularly conducive to enhanced propagation (and hence CCI) unless your predictions are poor on the detailed view of the Freeview tool.
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They are 99 or 100 mostly, with one 98. Now, something else comes back to me which I parked a few months ago due to lack of time. PSB3 from Wenvoe on 47 isn't working either and it used to. Everything else from there works, although it can be a bit iffy as it's off the side of the aerial.
And back to a couple of years ago in the middle of C**** everything became a bit unreliable and I stuck in a low gain masthead amp. to improve things which had become marginal. This is now getting a bit suspicious - I wonder if the cowboy has b*ggered the aerial, the connection, or the cable in to the loft from it (which was the only bit replaced in the previous incident).
Local muxes are more robustly coded (with lower data payload as a result) so lower S level works for them.
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I know, but coding doesn't affect the strength figure, only the ability to demodulate/decode.
 
So a log worked with 10kW erp before DSO and then the 100kW erp now (+10dB)... and then needed a masthead amp (minimum another 10dB typically?). Logs have a weak spot for water ingress according to Justin the owner of this useful website https://www.aerialsandtv.com/knowledge/aerials/log-periodic-aerials
NB The local is only 5kW erp (-13dB) aimed at Bristol (bearing of 15 degrees approx) via six stacked shrouded logs. Quite a tight beam.

As your log will now be well over 12 years old (Mendip DSO was early 2010?) it might be time expired from corrosion, wind rain and UV exposure? Particularly if near the sea? If your aerial man arrived on horseback he may have used cheap cable (RG6) rather than all-copper satellite grade such as WF100? Difficult to check cable type unless accessible via the loft (if cool enough).
Replacement with a group K aerial for 21-48 only might be required? Check out Justin's recommendations.

It may also be something local like a new or updated mobile mast/tower/pole that is overloading the amplifier or tuners?
https://restoretv.uk/ could help identify if that applies and provide a filter (though they'd need to send out an installer to fit it before the masthead amp. Mobile phone companies pay for that work, of course.
 
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