How to improve reception of UK DTT on Irish East Coast

ijc

Hello,
I am hoping that someone can give me some general advice on how to improve the reception of Digital Terrestrial Television.

While in the UK, I bought a Grundig GDT1500 Digital Terrestrial Receiver. I had heard that it was possible to use this where I live in North Wexford to receive the free to air channels broadcast from Wales.

I already receive analog BBC 1 and 2 Wales, HTV, S4C and Channel 5 pretty well using a roof mounted aerial with a booster box.

Sometimes I can receive all the digital channels, sometimes not. From looking at the signal meter of the Grundig box, it seems that when the signal is too weak to display the digital pictures, it is not too far below the threshold needed. So, I think I may only be looking at some solution to enable me to boost my reception a little. I have heard that something called a "high gain amplifier" may work for me. Has anyone been in a similar situation and tried one of these?

I'd be very grateful for any advice anyone has.
thanks,
Ian.

bkehoe

Hi,
What kind of antenna do you have?

Brendan

West Briton

My parents' house in Donegal faces across Lough Foyle to Limavady. Using an amplified indoor aerial, a flat plate one around one foot square for around €40 with built in AC powered amplifier facing out the window - on the ground floor only(!) I can get a usable signal on all the muxes. The attic aerial linked by red coax to the telly for analogue is of no use whatsoever. Note that with some aerials the higher the mux in the UHF band, the more critical the signal.

When I get a chance to go up again (hopefully over halloween) I'll report on the changed QAM and its effect.

DMC

A regular contributor and good friend of the ICDG boards, madman, is on the east coast Wicklow/North Wexford area and had the dubious honour of having a ITV Digital Sub!

He'd be yer man for this occasion...

ijc

Thanks for the feedback so far. In response to the type of aerial, it's a UHF outdoor aerial mounted on the roof, looks something like this:

/
-x-x-x-x-x-x
\

Well, if madman is reading this and can offer any suggestions or someone else can, please do.
Thanks in advance,
Ian.

Yeap, here I am, will help if I can.
Firstly it's location , location, location.
Some areas of North Wexford can be very lucky with presely.

Simple rules apply,a coast view and some height above sea level, help greatly.

In my experience near coolgreaney, signal has been strong enough 7 days out of ten with a basic grid aerial and mast head amp psu etc.
Travel towards Arklow or Gorey down to sea level and things get worse due to high ground on the coastline from Arklow Rock down to Tara hill getting between you and presely.

Your analog signal though on diferent channels than the DTT of course, would have to be coming in at around 70 or 80 db's or so for regular DTT to be there.
Obviously whatever favours having a good analog signal from a tx like presely that does DTT also, favours the DTT signal aswell.
Presely often suffers even in it's best areas over here in the winter months in wet weather, and even if that is only marginally affecting analog it can wipe out some of DTT.
Putting up a twin or quad set of aerials will have a major effect and now that there are more fta channels coming on stream with music and the like and indeed for the excelent BBC news 24 , the cost might be worth it.

Another thing worth noting is that, the Irish version of DTT seems to be on hold,if it launched, your UK DTT signals would be completely wiped out and indeed probably analog presely as well as the same channels were going to be used.

A lot of local aerial installers may not be too familiar with UK DTT and there are some who are fascinated by it! depending on who you use. But regardless they should be able to improve your analog reception depending on what you want to spend.
By doing so there will be a noticeable improvement in your DTT.
As you are already getting DTT some of the time that is a good sign.
Regularally during the summer and this is amazing, I've seen the meter on my ITV digital box reading 3 out of a possible 4 and in green which is top quality.
Of course there would be other days when there is that red dot
You can p.m me if you wish, and I will try to give you more specific pointers.
mm

DMC

mm, can you advise on wheather or not the signal has increase recently, with the impending launch of Freeview. I have read on English forums that they have advised existing ITV Digital box owners to download new channel information or summat like that. It appears that BBC THREE now appears instead of BBC Choice, and that the radio stations, 6 Music and 5 Live have appeared.

(Have to test a DTT box at home soon!)

That is correct Damo,there was actually a promo advising of the channel change on BBC 1 wales last night, don't know if it was on NI.A lot of the newer ITV boxes will do the update automatically.
There is a programme for increasing strenghts from UK DTT tx's.
As of a month ago, Presely was not on that list

According to the current stuff on the BBC website the presely erp ranges from 0.5 kw to 1kw, whereas Winter hill which I think serves manchester has an erp of 5kw.

Based on whats getting here at present, an erp like that from presely, with the seapath would be a heck of an improvement.
I'd imagine they are still very restricted though with the older technology in terms of interference risks to the multitude of analog tx's.


I don't currently have the ITV box hooked up so , am not up to date on what signal has been like lately but will attack this tomorrow.
mm

marclt

Not all the signals in the UK have been upgraded as yet... eventhough the channel information and new epg listings came on stream during the week.

1xtra BBC, 5 Live and 5 Live extra along with BBC 6 music, BBC 7 and BBC world service are to be broadcast on freeview.

New channels are also coming on stream like f tn, TMF and UKhistory plus UKHomestyle, which I guess is like UKstyle?

Anyway, I have relatives who live in Wexford town - I used to live there so I'd be interested to hear what you can get etc etc...

Good Luck!

tvman

1st post from tvman!

I have just discovered this board and have joined.

My first question is about UK DTT. I live in North Louth - 55 miles from the Divis tx.
I have no problem with analogue reception, as I have a choice of two transmitters (Divis and the Camlough relay).
Any of you that can receive UK DTT along the East Coast, would you expect to get reliable DTT at the distance I live from Belfast.
I do not want to buy a DTT STB and then discover that I have no reception.

Regards,
tvman

I live in Sligo and i have a Pace DTVA,i done a re-scan and up popped 22 BBC channels but no U/ITV or Ch 4/5 which i previously had.The strength of the signal has improved a nice wee bit so i expect the signal from ITV/CH4-5 will come on in due course!

Originally posted by tvman
1st post from tvman!

I have just discovered this board and have joined.

My first question is about UK DTT. I live in North Louth - 55 miles from the Divis tx.
I have no problem with analogue reception, as I have a choice of two transmitters (Divis and the Camlough relay).
Any of you that can receive UK DTT along the East Coast, would you expect to get reliable DTT at the distance I live from Belfast.
I do not want to buy a DTT STB and then discover that I have no reception.

Regards,
tvman

Hello tvman.
you would need to be using Divis for DTT as no relay in NI outputs DTT.
The analog reception has to be very , very good from Divis for to be getting DTT.
I have read posts on this forum where reception of DTT around Newry from Divis has been unreliable.
so it's not likely (but not impossible) that Dtt would work where you are. There is a lot of high ground even between north Louth and Newry so that might rulke it out-but then you could be lucky and the signal could be skipping through and between hills to your location.
Best to borrow the kit from somewhere and check it ou first
mm

tvman

Thanks to madman and zorro2566.

A bit more info and items I picked up from other sources.
Where I live reception from Divis is a good as it can be, I have almost line of sight with the tx - except for the earths curve!!!
The high ground around Newry does no come between the rx and tx sites there is a narrow valley there, in fact I can receive Divis on an indoor aerial to a watchable degree.
All this does not prevent the dreaded High pressure syndrome though during the “Summer”.
For that reason I use the Camlough relay which has one of the highest ERP's of all the north’s relays - 630W, is only about 15 miles from me and gives A1 reception. (I suspect though that the tx aerials are not configured to radiate at that power in southerly direction(eg Downtown Radio, same site) - the relay is almost on the border, and I believe uses such high power so as to counteract the high erp of RTE's Clermont Carn (same ae. group and pol.).

Getting back to DTT - highest power output from Divis now is 2.3Kw and is omnidirectional (I think).
If the plan to up the ERP of all main DTT txs’ goes ahead that may change things.
Anyway I could email forever about what I might pick up, so I will have to get my hands on a DTT converter somehow and see whats’ there, problem is I do not know anyone who has one.

On the subject of relays being equipped for DTT, I understand that DTT will be ok in a lot of areas where an analogue relay was required. This is because the digital video broadcasting standard overcomes the big problem of ghosting - one of the reasons for having a relay at all.
Also DTT txs’ do not need the same power to cover the same area as analogue.

Finally can anyone tell me the actual miles they are from any UK DTT transmitter and can receive it.

Thanks from tvman.

lawhec

UK DTT reception in the Republic is fairly OK around the border areas of the Republic provided you are receiving one of the three main TX's - I've heard of reception in Moville (Inishowen), Cavan Town, Sligo (as Above) and also in N.Louth. I haven't much experience with DTT, seen it a few times working and fiddling with the menus. Looks good at least on first impressions.

For that reason I use the Camlough relay which has the highest erp of all the north’s relays - 630Kw

Either that's bad information or a badly added "K"! Camlough is 630W. Although a reasonably powered relay it isn't the most powerful - Newcastle, Derry and Strabane all have higher powers than Camlough. My understanding of the relay is to serve the Newry area, particulary in the city where two low powered relays also are currently in service.

Getting back to DTT - power output from Divis now is 2.3Kw and is omnidirectional (I think). If the plan to up the erp of all main DTT txs’ goes ahead that may change things.

The 2.3kW power output is for Multiplexes 1, 2, A & B. Multiplex C has 1kW and D has just 800W. Multiplex C is also on Channel 48 - out of band for group A. There are plans to double the power of Muxs C&D but a date hasn't been set. There is also the added complication of Ch.34 also being allocated to Clermont Carn for DTT services, but that is of no concern in the short to mid term. Analogue TV services from Divis are Omidirectional but I'm not sure if DTT is.

Ideally all the Multiplexes on Divis should be running on around 5kW. This is based on the general rule that DTT can achieve the same coverage as it's analogue equivalent with 1/100th of the power (or 20dbW less). Obviously they are running underpower, Muxs C&D massively so. Brougher Mt. is just as bad, all running at 500W each (this is to protect RTÉ services in Donegal), Limavady fares better at 800W each. The move to 16QUAM seems to have provided a marginal improvement for reception. It remains to be seen how far it will extend coverage with existing powers. I'm hoping to get a lend of a box soon, one here at home which is well inside the coverage area for ATT & DTT from Brougher Mountain, and also another house which is on the fringe of reception for ATT from Brougher and which according to the Postcode database for 64QUAM isn't possible to receive DTT.

On the subject of relays being equipped for DTT, I understand that DTT will be ok in a lot of areas where an analogue relay was required. This is because the digital video broadcasting standard overcomes the big problem of ghosting - one of the reasons for having a relay at all.
Also DTT txs’ do not need the same power to cover the same area as analogue.

Quite a few of them are, but some of them are there to fill in black spots, particulary in South Down, Antrim coastline, Derry City (not all of it receives Limavady well), Strabane and also possibly Camlough along with a few other smaller powered relays, but nowhere near the 44 that currently exist. It's a crowded UHF band up here, so my guess is that for Relay stations a Multiplex 0 will be created carrying the 5 terrestial services run in parallel with the analogue services for a while, say 18 months. When the Analogue switchoff is due messages will be superimposed on the screen etc. telling viewers to swith to digital. Once these Analogue TX's are switched off these frequencies would then be used for DTT. In Main TX coverage areas where relays exist because of ghosting but which has good DTT levels from the main TX, they may be more keen to switch these off first as this obviously clears frequency spectrum, followed by the out-of-area relays then the Main TX's.

I have read posts on this forum where reception of DTT around Newry from Divis has been unreliable.

I see that a secondary transmitter on Clermont Carn using channels 23, 26, 29 & 33 is also allocated there with a 1kW power. Is it actually running and if so surely that doesn't help matters.

tvman

Hi Northern Correspondent.

The KW was a definite mistake and the relay ERP's was just taken from memory - I should have checked before submitting.
Anyway I have now edited the post and thanks for the correction.

Regards,
tvman.

TVman,
From your description, you may have luck
If you are receiving Divis with an indoor aerial without an amp in normal conditions then , you should have a great chance with the proper grouped outdoor roof aerial and amp.
But do get a good one, it's worth it.

I am receiving Presely at more than 120 miles from the tx-but virtually all of that distance is over a clear sea path which helps a lot.
I can get indoor aerial reception from presely without an amp.
Go for it.
mm

tvman

Thanks Man.

rx at 120 miles....sounds good. I will have to get my hands on a DTT receiver.
Next time I am in Newry I will call to a few of the independent retailers and see what they can do - I could even rent a rx for the day.

You probably have seen it before, but I have (I hope) attached a jpeg of Presely Tx.

By the way have you experimented with DAB - that's next on my list.

Cheers from tvman

marclt

Two websites that might be able to help you here...

www.maplin.co.uk - you can buy all sorts of gadgets on this website and they're competatively priced too!

www.maxview.ltd.uk - thet manufacture high quality aerials... and have booklets *free* to give you advice...I'm sure if you emailed 'em they'd be able to help also.

I used to live in Wexford town... and still have family there.. so let me know how you get on - I'd be interested to know!!