Missing Preseli channels

TAPlank

I am based in south Wexford and until storm Ophelia I got good TV reception from the Preseli transmitter on channels from 39 to 46. ALL of them dissapeared that weekend and some sporadically re-appeared. Just now one is working and all others show low signal strength and very low quality.
Is there a known problem and if so is there a fix?

The Cush

"Possible Weak Signal" according to the DigitalUK - http://www.digitaluk.co.uk/operations/planned_engineering_works

Thurston?

TAPlank wrote: »

I am based in south Wexford and until storm Ophelia I got good TV reception from the Preseli transmitter on channels from 39 to 46. ALL of them dissapeared that weekend ...

If it seems storm-related, then maybe your aerial was damaged. Have you inspected it for obvious damage?

FRIENDO

Your aerial may be the problem, working fine in north Wexford

TAPlank

I was thinking that perhaps the storm affected the transmitter, that now may not be the case. The aerial is a new, replacement one, installed about a week before the storm and there is no obvious signs of damage, I am now wondering if the cable connection was sommehow affected. I will have that checked, but it will be a week or two before I can get it done. meanwhile I will keep watch to see if the missing channels show signs of life.

Thanks for the replies, I will post the outcome here.

FRIENDO

TAPlank wrote:

Thanks for the replies, I will post the outcome here.

Hopefully you get it sorted, the aerial may have just moved in the storm, however you would probably notice if it changed direction.

TAPlank

No, the aerial has not shifted. I have something new to add to the situation. As I said it is a new aerial, probably of higher gain - I dont have the figures. On the day it was installed it connected to several other UK Regions plus Canal 5 from France a Spanish programme. In the earrly hours of to-day, Sunday, all but channel 45 were working, this morning only channel 43 is working and the Strength and Quality of the relevant Channels are: C39, S42, Q21. C40, S54, Q68. C42, S42, Q28. C43, S58, Q92. C45, S26, Q0. C46, S26, Q0.
Is it likely that other regional channels are now blocking mine and the the storm is not a factor?.

Thurston?

TAPlank wrote: »

... Is it likely that other regional channels are now blocking mine and the the storm is not a factor?

No, even if there are potential intereferers, their levels relative to your wanted channels won't have been altered, & there certainly haven't been consistent 'troublesome' atmospheric conditions over the past 2 weeks. (Though you might be in for a bit of that around Tuesday.)

Three of your poorest muxes (chs. 39, 42, & 45) are the com. muxes, which are half the power of the PSBs. Ch. 46 is a PSB mux (the DVB-T2 HD mux), so there must be something else going on there.

TAPlank

What puzzles me is that most channels were there at 1.00 am on Sunday and had vanished at 10.00am. When I get to it I will look for faults with the aerial connection, the masthead amplifier and the indoor amplifier distributor. Can't think of anything else to try, other than maybe to repair the old aerial and put it back up.

Thurston?

Well unless they have knocked the power back a bit at the transmitter for some reason.

Don't know where detailed info about works are to be found, unless maybe after the fact at a site like MB21, or if someone in the know at another forum happens to post.

Gerry Wicklow

All Ok according to this

FRIENDO

I checked out the BBC website and interactive map posted by the Cush above.
Entered a postcode for Saint David's, Wales.
Both Preseli and St. David's transmitters are working fine,
"Coverage prediction good"

Also all station's working fine at my place.

I suggest if you paid an installer to put up the new aerial, is to call him back.

Also it might be worth checking what aerial you have installed, I'm using a group B aerial.

I have tried a wideband aerials in the past and have found the group B aerial a better job.

George Sunsnow

Interestingly,I’m having the same problems after Ophelia ,I’m up in Arklow
Never had a problem before
I didn’t think to look here
Basically some drop outs for a few seconds like as if the signal is just dipping below threshold

New hd channels on a ch 33 mux have appeared,I was able to watch them last night eh bbc news hd,4seven hd etc
They’re gone this morning so I did a retune earlier and all channels are appearing EXCEPT anything on the mux that’s on ch45 eg sky news
I tuned it manually and got it but there’s some break up on it

It’s as if a new mux at some other transmitter has been turned on

There is another possibility which I’ll check this evening and that’s my distribution amplifier
Preseli has a habit in certain weather conditions of getting really strong which overloads and interferes with all other channels at times
One cable does not go through that and is unaffected
There’s no tv on that at the moment
Has the OP got a distribution amplifier?

I’ll get the aerial checked out at the weekend,I’ll also ask some of the neighbors

Btw which presumably welsh tx (possibly redruth or caradon down in the SW which often come in here) has hd channels and forces tv on ch 33?

mrdtv2010

Do not adjust your set: its tropospheric lift!! Freeview are advising their UK viewers that they are experiencing reception problems due to the weather: on the BBC News web site now as a trending story. Its classic at this time of the year: cold, dry conditions. And just wait for the fog...

http://www.bbc.co.uk/news/technology-41836518

The nearest CH33 interim multiplex to you is Mendip, not Caradon Hill which does not use this frequency.!!

George Sunsnow

Thanks Mrdtv
Crikey how far away is mendip?

Only ch 45 is affected this evening
I’ve had this since dso and never had this level of interruption before here

Some drop outs occasionally on the Arklow saorview tx too :eek:

mrdtv2010

Mendip is the main station for the Bristol area. IIRC that mux is about 72kw versus 20kw from Preseli. In South East Ireland the aerials pointing towards Preseli will 'see' Mendip behind Preseli, but normally the levels are too low. You can do a google maps fix on the distances, its well over the radio horizon. But in the current weather conditions tropospheric lifts will bring in distant transmitters such as Wenvoe/Carmel (South Wales) and Mendip (Bristol). they are not reliable.
More frequent visitors are Redruth (20kW) with a straight sea path to Ireland and the belter, Caradon Hill, 100kw which has a massive mast. Again they are far away and infrequent visitors.

In my UK address I have the local Crystal Palace station and Hannington which is 50 miles away. But my Hannington direction is the same as Mendip which is a further 60 miles on: and guess what, in the lift conditions I get BBC1 West and ITV West. Especially in the cold weather and in the fog its clear as a bell. As they say the mighty Mendip mast gets about, You can read more about it on the bigtower and mb21 web sites. Equally Mount Leinster and Clermont Carn will be appearing in the western UK seaboard.

FRIENDO

From Freeview on facebook

"We're aware that high air pressure is currently affecting TV and radio signals for some viewers in England and Wales. We're unable to prevent or remedy this, normal services will return once the weather changes."

TAPlank

FIXED I think!. A long distance look at the aerial from a nearby road showed it to be tilted upwards by maybe 15deg. It also showed that it was mounted a few inches lower than the original and closer to a Saorview one. None of this was obvious when viewing from below. Despite this many of the missing channels would come and go from time to time. It is now levelled and all channels are back, hopefully to remain.

This was a good excercise in getting help and showed the power of the Net.

Many thanks to all contributors.

Good Bye!

Thurston?

TAPlank wrote: »

A long distance look at the aerial from a nearby road showed it to be tilted upwards by maybe 15deg. It also showed that it was mounted a few inches lower than the original and closer to a Saorview one ...

It mustn't have been clamped properly if it ended up like that. Problems caused by wind are usually a pretty obvious case of something bending or breaking.

TAPlank

It was fitted with wing nuts, now has SS bolts and nyloc nuts.