Freeview on the border.. what is needed?

mustImprove

Hello everyone,

I live on the border and I was thinking about buying this set top box from amazon.
According to the freeview transmitter website my house is just about covered with the freeview signal.
At the moment I have a sony bravia that has digital but only mpeg-2 format so I can get a list of digital channels but I cannot get picture- just audio. While I can see all the RTE tv and radio listings it does not pick up any uk listings on digital (the analogue aerial on the roof can get them).

Would an outdoor digital aerial be required to pick up the UK channels digitally? Would the Toshiba box I linked be compatiable with both freeview and soarview?
Thanks alot

ardmacha

the analogue aerial on the roof can get them

If you need an aerial for analogue then you'll need it for digital, especially at present as these services are not at full power. Can your TV not receive UK digital when connected to the outdoor aerial? You won't get HD just yet.

mustImprove

Thanks for the reply ardmacha. The tv can pick up the Irish channels digitally but it is audio only as its an older model tv with mpeg2 (not mpeg4).
I don't have an outer digital aerial but I am thinking about getting one although I imagine the installation might be awkward in terms of wiring.

Peter Rhea

There's no such thing as a digital aerial, although some may claim to be 'optimised for digital reception'.

All you need is a UHF aerial of the same channel group as the transmitter (or a wideband which covers all transmitters) & enough gain to suit conditions at your location.
This of course assumes that there is some kind of signal available at your location. As mentioned above, the transmitters are on low power until the analogue broadcasts are switched off.

Where along the border are you?

ardmacha

While I can see all the RTE tv and radio listings it does not pick up any uk listings on digital (the analogue aerial on the roof can get them).

So you have a digital TV which can pick up UK stations on analogue, but not on digital?

Peter Rhea

It's possible the OP is receiving from an NI relay transmitter (no Freeview till next year) or just has poor reception from a main transmitter, which is further compounded by the low powers used for digital atm.

mustImprove

Thanks very much for the feedback guys, I really appreciate it.

@ardmacha - you're right, since we are so close to the border we have been getting a good (analogue?) signal to watch the UK channels for the last 20+ years. However lately bbc1+2 have gone down in quality a little with cuts in the picture around ever 10 seconds.

@Peter - Thanks for the advice I didnt know that. Please excuse my ignorance but would a UHF aerial be the same aerial we have on the roof the last 10 years? I mean it's not a different type of aerial required for digital? I am in donegal bordering fermanagh and the 'Brougher Mountain Transmitter' covers my location (according to the map).


The TV only got mpeg2 decoder so I can get a listing of digital channels and get audio but no picture. If the UK digital signal reached my house I should in theory be able to pick them up too? Its not a different frequency?
I would be happy in the knowledge if I bought that box in the OP that say in 1 year it could pick up the Irish and Uk channels.

Sorry I am not too familiar with this but I am slowly learning.

Peter Rhea

mustImprove wrote: »

. . . since we are so close to the border we have been getting a good (analogue?) signal to watch the UK channels for the last 20+ years. However lately bbc1+2 have gone down in quality a little with cuts in the picture around ever 10 seconds

'Cuts in the picture' sounds like the kind of problem you would see on a digital broadcast which has a low signal level or is subject to interference.

Brougher Mountain multiplex 1 (carries BBC 1, 2, 3, CBBC & BBC News) is broadcast on UHF channel 30 which is also used by Hollywell Hill transmitter (near Derry) so there would be conflict if both signals can be received in your area.

Are you sure you don't have these other BBC channels? BBC3 would be channel no.7.
On an analogue channel, cuts in the picture would suggest some serious reception fault or strong interference.

mustImprove

We had perfect bbc until a year or two ago so as you say it must be the digital interefence. The cuts aren't as noticable on the good tvs but the older ones give that awful sound and the snowy background for a few seconds.
Also I believe the aerial on our roof is not ideal, I know we dont have the aerial attachment required for tv3/tg4 but we still pick them up in ok. we had someone out to look at it but he was saying it would be better of getting a (better) satellite with multiroom and waiting for digital.

BBC3 would be channel no.7.

I did a retune of the digital and it picked up all the saorview channels and radio but there is no signs of any uk/bbc channels. do you mean channel no. on digital? as in 007? that is RTEjr for me - im sure i mistook what you meant there?

So we actually will need to get the aerials on the roof sorted to get good quality digial receiption? The repairman had me thinking that they would be coming down when digital tv took over and its "not worth it" ha.

thanks alot for the help:)

Peter Rhea

mustImprove wrote: »

We had perfect bbc until a year or two ago so as you say it must be the digital interefence. The cuts aren't as noticable on the good tvs but the older ones give that awful sound and the snowy background for a few seconds.

Snowy background would mean it's an analogue channel you're viewing; you say this happens every 10 seconds? How is that even watchable?

Either there is something seriously wrong with your aerial setup or there is a strong source of interference nearby.

mustImprove

it only happens on bbc1 and bbc2 on the smaller portable tvs. In the main rooms it not too noticable, it will knock off the text if its on and you will see the odd flicker.

yes, so far the only tv i have watched is analogue. The only tv with digital is mpeg2 (not mpeg4) so I can only get a listing of digitial channels with no video from it.

I just came here to get some advice on what people with more knowledge would recommend I do and whether I might be able to receive uk freeview at my location.

thanks

lawhec

The coverage map linked to in the opening post should not be trusted - the software used to generate it is only set up properly for the GB grid reference, not the Irish grid reference, therefore gives false results. For example it shows that Omagh has no coverage from Brougher Mountain when that clearly isn't the case.

The location "Donegal near Fermanagh border" could mean any place from around Ballyshannon/Bundoran to just north of Pettigo; Brougher Mountain reception may be possible, but so too might reception from Strabane or Gortnalee. To be sure your current BBC1 analogue pictures are from Brougher, the TV needs to be tuned to a frequency of 479.25MHz or close to it, or channel 22 (displayed as E22, C22 or UHF22 normally). If it is not, then your signal is not coming from Brougher.

mustImprove

Thanks lawhec.
Sorry I meant to say i am literally a few feet from the border just outside belleek town, if belleek gets coverage then i definitely would too I imagine.
I went into manual tuning but it will only let me go from 1-69 in frequencies (bbc1 is on C 21).
Really appreciate the input guys.

So the aerial on the roof which I thought was for analogue input does have a big affect on digital? So a digital box will require an analogue input?

Peter Rhea

Gortnalee (mentioned above, a relay of the Limavady transmitter) has BBC1 on channel 21, BBC2 on 27, UTV on 24 & Channel 4 on 31. Freeview will not be broadcast from there until the Limavady station switches off analogue, sometime next year.

These smaller transmitters will not carry the full service, only the 3 public service muxes, but this includes all current HD channels. Your existing aerial would be fine if it was in good condition but there seems to be something wrong somewhere.

The digital services are carried on the same UHF radio frequencies as the analogue; in reality all wireless signals are analogue signals, the aerial on the roof certainly doesn't discriminate.

mustImprove

ahh the frequencies match up exactly with what you mentioned. Im very impressed how ye know all this.
I think our aerial is a little shabby - tg4 and tv3 especially dont have a great picture. I remember the fella who looking at the aerial said something like its complete chance we even get a picture for tv3 considering there was an extra attachment required for those (or something like that).

My final question and then I will stop annoying ye? Is there a one size fits all aerial? ha. so i can pick up everything.

thanks

Peter Rhea

mustImprove wrote: »

Is there a one size fits all aerial? ha. so i can pick up everything.

In effect, that's probably what you have already, unintentionally. The Saorview signal from Truskmore (Sligo) should be strong in that area & would be picked up on anything that passes UHF signals to the receiver.
How many aerials are on your roof? You already mentioned the lack of an 'attachment' for TV3, so there's probably a VHF aerial pointed at Truskmore for RTE. This aerial would be wider & have more space between its elements than the type used for the NI channels.

lawhec

mustImprove wrote: »

Is there a one size fits all aerial? ha. so i can pick up everything.

Well there is something radio enthusiasts use called a discone aerial that can do something like that, but it's not really intended for broadcast use.

Gortnalee won't actually be using the same frequencies for DTT broadcasts at the switchover, instead they'll be moving to 22/25/28 the same as the PSBs for Brougher (though the frequencies for the HD & UTV/CH4 multiplexes will be reversed, the HD mux will be E22 from Gortnalee and E25 from Brougher according to current plans - can't see any reason why all three can't line up themselves TBH). However any aerial aimed for Gortnalee's analogue services should be fine for digital when it comes. Despite being only 32 watts, Gortnalee covers a fair area at the western tip of Fermanagh including Garrison and Belleek and I've seen reception as far away as Bundoran. It's technically part of the Limavady transmission group as there's no line of sight to Brougher from the Gortnalee site, but there is to the Strabane relay.

RTÉ, TV3 & TG4 should be romping in around Belleek without too much effort from Truskmore, but from what yourself and the installer has said, it looks like you haven't the appropriate UHF aerial intended for TV3 & TG4, and that the current set up is a small VHF Band III aerial for RTÉ1 & RTÉ2 aimed at Truskmore, and a UHF aerial (either a 'wideband' or Group A model) aimed at Gortnalee, with TV3 & TG4 being received via the UHF aerial which is not only likely to be the wrong aerial group, but also the wrong polarity and also facing in the wrong direction!

mustImprove

Yeah there does seem to be a really good signal from Truskmore.

I went out and took a picture so you can see exactly what it is (dated most likely;) )

mustImprove

Oh that is infinitely helpful lawhec, great information there. thanks alot for taking the time to fill me in.
So basically if I were to get UHF aerial attached on to my existing setup I might be in business.
It's funny we got 2 people out to 'fix' the signal - the first guy spent no time looking at the aerial and just went to the attic and I dont even know what he did there.
The other guy who is a friend of my brother -well he more or less said get a better satellite and wait for digital ha.
I feel like I am well up to speed now and I should hopefully be able to get it going for here. cheers

Peter Rhea

That's more or less what I expected, the grid aerial is a wideband UHF design & along with the intended NI channels will also be picking up Saorview as well as TV3 & TG4 analogue from Truskmore as the UHF/VHF combiner should attenuate most UHF signal picked up on the VHF aerial.
At some point, certainly after switchover, the VHF aerial can be replaced with the appropriate UHF type along with a UHF/UHF combiner if Saorview reception on the 'wrong' aerial proves unreliable.

lawhec

mustImprove wrote: »

Yeah there does seem to be a really good signal from Truskmore.

I went out and took a picture so you can see exactly what it is (dated most likely;) )

That looks like a Truskmore VHF & Gortnalee UHF set up - the aerial higher up is a vertically polarised UHF "Grid" aerial which is almost certainly wideband (in that they intend to cover all UHF frequencies) while the one below is a simple 4-element VHF Band III Yagi for RTÉ1 and RTÉ2 from Truskmore. The dark blue box in the middle looks like a VHF/UHF combiner to feed the signals from the two aerials into the one downlead cable without affecting each other.

The use of a grid aerial at the top suggests that whoever installed this either is (a) an installer who commonly does installations around south Donegal where "deflectors" were (or still are) about as grid aerials as well as being designed to cover all UHF channels also have a wide forward lobe when horizontally polarised, or (b) an installer who picked up that there are 'ghosting' problems receiving Gortnalee; grid aerials are not ideal for use at the frequencies broadcast from Gortnalee, but they have good anti-ghosting properties when the unwanted signals come from the back and sides.

Edit: Adding from what Peter has said, an additional UHF aerial aimed towards Truskmore along with a UHF Group A/Group E combiner (the output of which should then be fed to the UHF input of the VHF/UHF combiner) would set you up properly for everything as it stands right now. A cheap but structurally sound aerial should be enough for clean TV3 & TG4 analogue and rock-solid Saorview. Once both Gortnalee and Truskmore switch off analogue TV, you can either remove the VHF aerial or as an alternative use, you could have it realigned towards either Brougher Mountain or Strabane if you want to try and listen to NI DAB services.

Peter Rhea

lawhec wrote: »

. . . but they have good anti-ghosting properties when the unwanted signals come from the back and sides.

It's not doing much to keep out Truskmore . . .

lawhec

Peter Rhea wrote: »

It's not doing much to keep out Truskmore . . .

Those familiar with Bill Wright's stories on TV & Radio reception may be familiar with him using the term "attenuator country" - when it comes to receiving Truskmore, Belleek would be in "attenuator country"!

mustImprove

lawhec wrote: »

Those familiar with Bill Wright's stories on TV & Radio reception may be familiar with him using the term "attenuator country" - when it comes to receiving Truskmore, Belleek would be in "attenuator country"!

ha yeah signals are all over the place around these parts
i could go to a neighbours and they would be the opposite to me.

Edit: Adding from what Peter has said, an additional UHF aerial aimed towards Truskmore along with a UHF Group A/Group E combiner (the output of which should then be fed to the UHF input of the VHF/UHF combiner) would set you up properly for everything as it stands right now. A cheap but structurally sound aerial should be enough for clean TV3 & TG4 analogue and rock-solid Saorview. Once both Gortnalee and Truskmore switch off analogue TV, you can either remove the VHF aerial or as an alternative use, you could have it realigned towards either Brougher Mountain or Strabane if you want to try and listen to NI DAB services.

Great! Im gonna get a UHF Group A/Group E combiner asap and have it installed. Hopefully the guy who installs it will be familiar with what you say..this time:rolleyes:
So basically that VHF will be worthless pointing in that direction once the uk switchover happens and i will have it realigned so we can get freeview.

many thanks

Peter Rhea

mustImprove wrote: »

Great! Im gonna get a UHF Group A/Group E combiner asap and have it installed. Hopefully the guy who installs it will be familiar with what you say..

You need the other UHF aerial too, or there'll be nothing to combine . . .

So basically that VHF will be worthless pointing in that direction once the uk switchover happens and i will have it realigned so we can get freeview.

All tv broadcasting on VHF is due to cease at switchover, your only chance of Freeview will be from the transmitter where you already have your UHF aerial pointed to receive your analogue signals. Would be worth finding out what is causing the breaks in picture, though.

Ronnie Raygun

lawhec wrote: »

The use of a grid aerial at the top suggests that whoever installed this either is (a) an installer who commonly does installations around south Donegal where "deflectors" were (or still are) about as grid aerials as well as being designed to cover all UHF channels also have a wide forward lobe when horizontally polarised, or (b) an installer who picked up that there are 'ghosting' problems receiving Gortnalee; grid aerials are not ideal for use at the frequencies broadcast from Gortnalee, but they have good anti-ghosting properties when the unwanted signals come from the back and sides

Ah, blow it out your ass, its probably just an installer who uses nothing but grids and wouldn't know his beamwidth from his bandwidth.......

mustImprove

Peter Rhea wrote: »

You need the other UHF aerial too, or there'll be nothing to combine . . .

You mean as well as the existing vertial one that is pointing towards Gortnalee or is that the one you are talking about?

All tv broadcasting on VHF is due to cease at switchover, your only chance of Freeview will be from the transmitter where you already have your UHF aerial pointed to receive your analogue signals. Would be worth finding out what is causing the breaks in picture, though.

So the VHFs will be pretty worthless in terms of digital after the switchover? Next year 2xUHFs should cover both freeview and soarview?

Yeah I'm gonna try and get someone out again to look at the break in signal. I noticed on amazon they sell digital tv strength meters. I wonder would this be any help in terms of setting up the aerials or would they be up to the task?

mustImprove

Ronnie Raygun wrote: »

Ah, blow it out your ass, its probably just an installer who uses nothing but grids and wouldn't know his beamwidth from his bandwidth.......

hey I didnt put that aerial up i swear :mad:

Peter Rhea

mustImprove wrote: »

So the VHFs will be pretty worthless in terms of digital after the switchover? Next year 2xUHFs should cover both freeview and soarview?

VHF (Very High Frequency) & UHF (Ultra High Frequency) are two consecutive parts of the radio frequency band, though not all is used for broadcasting. The broadcast VHF & UHF frequencies have also been divided into bands I - V, although only III, IV & V are currently used for tv, while FM radio is in band II.

UK tv is currently all UHF, as is Saorview & when the remaining RTE VHF analogue broadcasts are switched off, all Irish tv will be on UHF. The frequency band they occupy, VHF band III, will continue in use for digital radio (DAB).

Truskmore currently broadcasts RTE 1 & 2 on band III (VHF), while TV3 & TG4 along with the Saorview muxes are on band V (UHF, aerial group C/D, to complicate things further).

Since you seem to have no problems with reception from Truskmore, a simple, inexpensive UHF aerial (group C/D or wideband) should provide reliable Saorview reception & improved analogue TV3 & TG4, while these are still available. The installer may decide to use the existing grid aerial for this purpose & a grouped one (narrower frequency range, better gain) for the lower powered Gortnalee transmissions.

mustImprove

Excellent, thank you very much Peter Rhea and lawhec

lawhec

Ronnie Raygun wrote: »

Ah, blow it out your ass.

It's posts like this that make me glad that the Summer holidays end in a few days time.

lawhec

I forgot to mention that provisionally for now, at the switchover the ERP of the multiplexes at Gortnalee at to be 30 watts, compared to 32 watts for current analogue transmissions. Considering that the reckoning is for DTT coverage to match analogue coverage is at 1/5th the analogue power (which if my maths are right, would give 6.4 watts), Gortnalee should have an increased service area after DSO. Presumably the higher power is to combat possible co-channel interference from Castlebar and maybe Brougher Mountain as well.

Galway

Ronnie Raygun wrote: »

Ah, blow it out your ass, its probably just an installer who uses nothing but grids and wouldn't know his beamwidth from his bandwidth.......

A UHF wideband aerial should be avoided at all costs where all channels received are in group A as it gives very poor gain in this group. As was pointed out what you will need once analogue switchover has completed in NI is a good vertically polarised group A UHF aerial possibly with a masthead amplifier for Freeview from NI and a good group C/D horizontally polarised aerial (no amplifier needed) for Saorview from Truskmore combined into one downlead with an A-E combined (power pass on group A input).

Peter Rhea

Galway wrote: »

A UHF wideband aerial should be avoided at all costs where all channels received are in group A as it gives very poor gain in this group.

Inherently wideband aerials with fairly flat gain across the UHF tv band, like grids or log periodics shouldn't be lumped in with wideband Yagis. They don't have as great a gain penalty at lower frequencies, relative to their max. gain & also have useful radiation pattern differences that can be exploited, even in situations where reception of only one channel group is required.

As already mentioned in this thread, a vertically polarised grid has a tight horizontal radiation pattern which can be useful for rejecting off-axis signals. Logs apparently lack the troublesome side lobes of Yagis.
In a decent reception area, minimising interference should be more important than simply maximising gain, especially with digital transmissions.

It's not really useful to advise someone on what they definitely need, without a thorough on-the-ground knowledge of their reception conditions