Coverage Maps

lawhec

I've been playing about with a piece of software that allows you to make coverage maps from transmitters. I have here attached a map of the coverage from Divis Mountain of BBC Radio 1 (99.7 FM) and certainly going out westwards to Tyrone and Fermanagh it looks accurate enough.

I could try and do a few others if people are interested. Divis Radio is easy to do as their transmitting antennas are omnidirectional but if I've the polar plot of the transmitting aerials from other stations they can be done too.

DMC

:eek::D

lawhec

Carin Hill TV, for RTÉ 1 (UHF Channel 40)

This is a directional antenna with the main bearing pointing at Tullamore. For those not too in the know on field strengths, the red and yellow indicate the "core" coverage area, green is the fringe of core coverage while the blues are for fringe reception.

Mayo Exile

Beautiful maps! Can you do one for the Clermont Cairn mast in Co. Louth?

s_gr

Northern Correspondent wrote:

I've been playing about with a piece of software that allows you to make coverage maps from transmitters.
QUOTE]


What software are you using for this. Is it a planning tool like pathloss or something else. Would be interested in finding about it.

DMC

Fantastic stuff...

Would it be too much of an ask to do DAB from the North, incliuding Score?

Ulsterman 1690

Nice one NC although Ive picked up BBC Radio from Divis in places a good bit South and West of those on your map (and no not on mountaintops)

lawhec

Ulsterman 1690 wrote:

Nice one NC although Ive picked up BBC Radio from Divis in places a good bit South and West of those on your map (and no not on mountaintops)

I would well believe it - the 48dbuv/m measurement is set for mono coverage on an "average" radio with an aerial 10 metres above ground but many half decent sets will exceed this and be able to pick up weaker signals without too much fuss - especially car radios.

Incidently the BBC and Ofcom set 54dbuv/m as the coverage area for stereo reception which is the case of the Divis map is dark blue or better. Of course they assume an outdoor aerial is in use.

Clermont Carn - I have one done for that concerning RTÉ1, including its "northern" coverage, I'll put it up in a wee while. I was also measuring it for its predicted coverage for its DTT broadcasts when the trial gets underway but I was a little surprised by its predicted northern coverage (the aerials for DTT from Clermont only point south / south west) so I'm going to have to double check the measurements. I have a couple of Kippure and Truskmore VHF telly if anyone's interested? Score NI I'll be able to do, though with six transmitters it'll take a bit of time.

lawhec

Clermont Carn, coverage of RTÉ1 on UHF Channel 52. Bear in mind this is the lowest frequency TV channel from Clermont, the likes of TV3 and TG4 may be screened more.

From reading on measurements, red is core coverage, green is the edges of core coverage and the blues are "fringes".

Ulsterman 1690

likes of TV3 and TG4 may be screened more

Also to the West and South coverage on TV3 and TG4 would be limited by Maghera being cochannel (albeit with opposite polarity)

Wonder if anyone In Scotland or IOM actually watches RTE ?

NC I remember seeing some rather large Band 3 aerials in Larne. Any idea if these were for Kippure or Truskmore (come to think of it they may have been defunct 405 aerials ????)

lawhec

Yeah, my plots don't take into account any co-channel interference that could be possible though in the case of Maghera directivity and polarity would null much of that out.

Larne Band III aerials - I remeber being up there once and seeing a number of large ones, but this could have been down to reception difficulty from Black Mountain as the BBC had a Band I relay in Larne?

As for RTÉ, I believe there are some setups in Portpatrick. I have some distant relatives on the IoM who tell me that RTÉ can be picked up on the south of the island.

byte

Ooh, VHF coverage of Trusky would be great!

lawhec

A rough shot here - I'm not entirely sure what the minimum field strength needs to be for VHF Band III TV though.

Ulsterman 1690

Used to know but cant remember ill look it up and get back to you
For DAB 37dBuV/m is considered adequete and anything above 47dBuV/m is regarded as good but for analouge TV it would have to be higher

Richard

Northern Correspondent wrote:

As for RTÉ, I believe there are some setups in Portpatrick. .

I once received RTE on a handheld TV in Portpatrick! The line of sight give a much better chance of reception than in North Down.

Portpatrick is a bit odd anyway - I believe that Divis reception is better there than the local Cambret Hill relay.

BTW - Northern Correspondent - How does the software work? Do you input heights of mountains and so on in order for it to do its calculations?

lawhec

Ulsterman 1690 wrote:

Used to know but cant remember ill look it up and get back to you
For DAB 37dBuV/m is considered adequete and anything above 47dBuV/m is regarded as good but for analouge TV it would have to be higher

I found some measurements...

DAB - (measurement at the aerial socket) minimum required: 30dBuV, maximum 65dBuV. Therefore 37dBuV for adequete reception seems about right.

UHF Analogue Television - Band IV (21-37): minimum required: 58dBuV, Band V (39-68): 64dBuV. Though it must be said that many people can tolerate a picture with values a lot lower.

UHF DTT - Minimum Value: 32dBuV, Recommended: 45dBuV. I'm not sure if the minimum level applies to 64QAM or just 16QAM. I do remember in the On/ITV Digital days the receivers in general needed around 40dBuV, so some of the more modern sensitive receivers may get away with 30-33 at the bottom end of 16QAM and around 35-38 for 64QAM though in my experience the higher the signal level the better for tolerating man-made interference e.g light switches.

FM Radio - Stereo minumum: 54dBuV, Mono minimum: 48dBuV, though it must be said that many good radios (especially good car radios) can tolerate far lower levels especially in mono. I know that I've been able to listen to Q101 (from Brougher Mountain) in a car radio continiously as far south as the northern outskirts of Dublin before NTL leakage with Newstalk started destroying it.

Also, in the case of FM Radio and Analogue and Digital telly, the networks were designed for using an outdoor aerial at 10 metres above the ground. In the UK at least, DAB is being designed for coverage purpourses to work on a portable basis just 1.5 metres above the ground - coverage using a roof aerial is more again, and in my experience can vastly improve reception.

Away to do these Score DAB coverage maps...

lawhec

OK, three coverage maps for Score NI DAB (12D)!

The first one (green) shows locations where there is ground coverage (1.5 metres) with a minimum signal strength of 42dBuV in at least 95% of cases - which should be enough for portable listening without "bubbles" in open space or even indoors with careful postitioning of the whip aerial.

The second one (red) shows locations where the signal strength is a minimum of 30dBuV at 10 metres above ground in at least 95% of cases. In this case if you're in a red zone but not a green, you will almost certainly need an outdoor aerial minimum, and quite likely a directional one. A masthead amp that can amplify Band III signals could also help.

The final map (violet) is the same as the red map except this deals with coverage in at least 75% of cases.

Ulsterman 1690

UHF Analogue Television - Band IV (21-37): minimum required: 58dBuV, Band V (39-68): 64dBuV.

OFCOM use that that standard but COMREG consider 60dBuV to be adequete for both Bands 4 and 5

Incidently Claremont seems to waste a lot of power radiating out into the Irish sea ?

lawhec

Ulsterman 1690 wrote:

Incidently Claremont seems to waste a lot of power radiating out into the Irish sea ?

The polar plot I have for the transmitting aerials for Clermont Carn actually have a null for radiating into the Irish Sea (with an small exception for the Cooley Pennisula) but when there's nothing but open water there's little to stop most radio signals.

marclt

hi there

any chance of vhf for kippure and uhf mount leinster??

i'm watching here from south west wales - would be really interested to know what the plotter says!

marc

DMC

In the words of Jeannette Krankie.... fandabbydozzy.






(BBC DAB in Norn Iron? I'm being too cheaky now... )

lawhec

I have a plot here for Kippure VHF - needless to say its coverage is big! :eek: I'll have it up in a while. I'll get around to plotting Mt.Leinster (VHF and UHF) shortly as well.

BBC DAB isn't possible as I don't have the polar plots of the aerials and that goes for all BBC transmitters I'm afraid, with possibly one or two exceptions.

UPDATE: Kippure RTÉ1 on Channel E (VHF Band III)

Picture 1 - Coverage without map overlay
Picture 2 - Picture with map overlay
Picture 3 - Closeup on coverage in Wales
Picture 4 - Closeup on coverage along the Down coast, Isle of Man, Lake District and SW Scotland.

rlogue

This is probably one of the best threads ever on ICDG!

Freddie59

rlogue wrote:

This is probably one of the best threads ever on ICDG!

As they say in the Amstel ad: Ehhhhhh.....no! You'd probably have to go to the satellite forum and look at, say, the ITV FTA thread!:eek:

DMC

Er, no. Having read every single post on this board, this is certainly one of the best threads.

BTW, the campaign threads of 4 or so years ago, were easily in my top 3.

lawhec

1. Mt.Leinster VHF TV (RTÉ1 and RTÉ2)
2. Mt.Leinster UHF (TV3 & TG4)

marclt

Thanks Northern Correspondent!!!

Ulsterman 1690

I thought Mt Leinster had a null to the East to "protect" (largely non-existant ?) Band 3 PMR transmissions (and former 405 line transmitters) in the UK mainland

NC any chance of Brougher or is that one you dont have a polar plot for ?

Capt'n Midnight

Thanks
Is it possible to do a map with contours showing the height of aerial needed to reach the signal - say up to 30 meters or whatever the normal maximum is, because most people would need one anyway ?

This is one I found a good while back for - no signal strength though,
http://www.ukfree.tv/maps.php - Pick Wales / NI / UTV transmitter on the right - with wales you can just about see pixels in Wicklow

other map refs
http://www.wolfbane.com/articles/tvr.htm - not so good as the irish maps are just circles - may have more in future

Pal

ITV Maidstone spreads into France a good bit.

pixel map is not accurate for wales spread
Only 1 or 2 pixels in ireland.
reality is all the wexford coast and parts of wicklow are working

lawhec

I thought Mt Leinster had a null to the East to "protect" (largely non-existant ?) Band 3 PMR transmissions (and former 405 line transmitters) in the UK mainland

There is a null, however it is only in the region of 4db down between bearings on 090 and 190 degrees. It can be seen on the map where the signal goes out to sea - the areas where there is a "kink" mark the boundaries of the power restrictions.

NC any chance of Brougher or is that one you dont have a polar plot for ?

I don't have a polar plot for TV from Brougher I'm afraid - radio might be possible if the plot for Q101 holds the same restrictions for BBC Radio. I'll check the plot for Downtown as well to see if they can match up.

Is it possible to do a map with contours showing the height of aerial needed to reach the signal - say up to 30 meters or whatever the normal maximum is, because most people would need one anyway ?

Such a coverage map really isn't possible because of the varying signal strengths at short distances. It would be possible to plot a map for the field strength to be measured a certain distance above the ground (see the DAB maps) but that's the "height" of it.

BostonStrangler

NC, any chance of one for 3 Rock TV ?

BostonStrangler

Northern Correspondent wrote:

Carin Hill TV, for RTÉ 1 (UHF Channel 40)

This is a directional antenna with the main bearing pointing at Tullamore. For those not too in the know on field strengths, the red and yellow indicate the "core" coverage area, green is the fringe of core coverage while the blues are for fringe reception.

http://www.irish-tv.com/cairnh.asp

The Irish TV website's RTE pamphlet copy of tranmitter coverage from the 80's (?) is nearly spot on to NC's nifty piece of software. Uncanny.

lawhec

Three Rock UHF TV coverage (from RTÉ1 E29 to TG4 on E55).

Picture 1 - All of Ireland
Picture 2 - (maked 4 here) a bit closer up...

More later...

Ulsterman 1690

NC do you have polar plots for Black mountain (as opposed to Divis) for Channel Five and Citybeat/Cool/U105 ?

lawhec

Ulsterman 1690 wrote:

NC do you have polar plots for Black mountain (as opposed to Divis) for Channel Five and Citybeat/Cool/U105 ?

Five? No

Cool / Citybeat / U105 - Yes, I'll do they soon.

lawhec

OK, after a bit of a lull, I've got ones done for the ILRs at Black Mountain, namely Cool FM, Citybeat and U105.

As well as power differences, according to OFCOMs data Cool FMs transmitting aerials are 232 metres up the mast, with Citybeat and U105 both at 190 metres - this would initally suggest that they're using the same aerial but their polar plots are different, in particular U105 doesn't have as big a null towards the NE that Citybeat has?

I'm also going to try and ask the BBC and Comreg if similar polar plot data is available from themselves (a request from the freedom of information act may be in order concerning the BBC!)

Ulsterman 1690

Thanks NC !

rlogue wrote:

This is probably one of the best threads ever on ICDG!

I totally agree -NC for Prime Minister ! :cool:

watty

Looks like a plot from Radio Mobile I use it for Repeater coverage and Microwave links.

See http://members.boards.ie/watty/limerickcoverage.htm

and
http://members.boards.ie/watty/ei2mrepeaters.htm

You can click on dots and not a scrap of Java!

If it Radio Mobile you can create contour lines and merge with MS Mappoint to get roads and towns etc.

I have some quite detailed maps of Limerick area / Shannon Estuary for planning potential 1260 MHZ / 1300 MHZ Amateur TV repeater. You will be able to legally view the input transmission or output, but Transmission needs a Comreg Wireless Experimenter Licence.

AN analog satellite receiver with an LNA (Low Noise Amplifier) or simply an aerial if closer will receive.

Later we hope to experiment with DVB-t and DVB-h on 436MHz, 1260MHz and the 5GHz band and maybe QPSK DVB on 10GHz

watty

Great work Mr. Northern Correspondant.

If it is "Radio Mobile" not a trivial program to use!
http://www.cplus.org/rmw/english1.html


If it is something else where can I get it?

Up to 300 MHz it is reasonalble results.

UHF TV , WiFi, Mobile Phone etc the problem is the only data publically available is quite low resolution from SRTM.

In the USA, the taxs pay for the equivalent of Ordinance Survey, so anyone can get the detail terrian info free.

In Ireland the Taxes pay for the Irish Ordinance Survey who then chargew MEGA MONEY for small areas of map /terrain in computer form.

The Maps in the shop arn't cheap either.

watty

Hmm he seems to have done an update. I will see if the SRTM2 data is any higher resolution for Ireland.

I found that the 433MHz plots are only a rough indication, but the 144MHz plots are very accurate.

VHF FM Radio 88 to 108 MHZ.
DAB 175 MHz
PMR446 446MHZ
UHF TV 470 to 860 Approx.

watty

DMC wrote:

In the words of Jeannette Krankie.... fandabbydozzy.
(BBC DAB in Norn Iron? I'm being too cheaky now... )

I'm confinced that with a big enough aerial I could get DAB here in Limerick, maybe from Arra Mountains, North of Limerick. I have access to a repeater site.

Actually I have talked on 145MHz FM into Portadwon direct and Enniskillen via West Tyrone repeater. But the conditons were good.

The "what ever it was " for 3 days in November was staggering. I was working the Dundee in Scotland repeater from the house with 2W at one stage and the Belfast (Hollywood hills) repeater (145MHz FM) mobile in the car at 50 W on old Adare Rd near Limerick!

Best on VHF I have had was 5W contact to Aberdeen on 144MHz using SSB.

With the big 10 element Yagi I can talk into Wales, Devon and Cornwall from here most of the time with 10W SSB on 144MHz.

There is a clearish path to Mt Lienster, so I can work the 433MHz band repeater there from Patrickswell with about 10W FM. Some days I can hear it on a hand held.

On a hill top near Ballingary (between Cork and Killarney road out of Limerick) I can have a good conversation with 0.5W on a "rubber duck" hand held on the 433MHz band to Mt Lienster.

lawhec

Watty, the program is indeed Radio Mobile. As you say unless you know what you're doing it is quite a daunting program to work with but once you've found what it is capable of doing it is a nice piece of software to work with.

Certainly for many of the coverage plots which extend into Northern Ireland it seems failry accurate - not a bad programme for free!

I know that one other person here (they can reveal themselves if they want!) was experimenting with the program, don't know how they got on though. The main important thing is though that you've broadband internet access otherwise downloading the maps will be painful.

Ulsterman 1690

In Ireland the Taxes pay for the Irish Ordinance Survey who then chargew MEGA MONEY for small areas of map /terrain in computer form.

Correct to a point. The Irish ordinance survey although part of the government doesnt recieve any state funding and is therfotre required to turn a profit/break even by charging extortionate prices for mapping data.

O/S data in most countries is considered a public service almost part of the essential infrastructure. Having this data readily available at very low cost means all sorts of innovative services (like multimap and GPS mapping services) become possible which in turn leads to massive benefits to individuals and cost savings to businesses (for instance delivery drivers dont spend half the day going around in circles trying to locate addresses) and of course profitable businesses mean more tax revenue but the short-sighted gobdaws in Government dont see it that way :mad:

I'm confinced that with a big enough aerial I could get DAB here in Limerick, maybe from Arra Mountains, North of Limerick.

Maybe you should set up a "deflector system"

in particular U105 doesn't have as big a null towards the NE that Citybeat has?

Citybeat's null might possibly be to "protect" some station in Scotland (Southwest sound on 96.5 perhaps ???)

lawhec

Ulsterman 1690 wrote:

Citybeat's null might possibly be to "protect" some station in Scotland (Southwest sound on 96.5 perhaps ???)

Sorry, my mistake - the null goes North-West, not North-East! (towards Cookstown & Magherafelt)

watty

watty wrote:

The "what ever it was " for 3 days in November was staggering. I was working the Dundee in Scotland repeater from the house with 2W at one stage and the Belfast (Hollywood hills) repeater (145MHz FM) mobile in the car at 50 W on old Adare Rd near Limerick!

It's trophospheric ducting from High pressure Watty.
It makes radio and TV signals travel much further than normal.

Today,I'm getting reception on UHF TV from all over Britain.

These map the predicted overspill/extended coverage at any time.

Currently pressure is very high at circa 1038 mb so the effects are good.

The only downside from a TV point of view is that a signal from far away could interfere with a local one causing wavy lines or co channel interference on the TV picture.

watty

Tropo, ducting. Lift...
Yes well I think there are a couple of different mechanisms. The on ein November was very unusal as it was steady. prolonged and without fading.

Some "lift" events I think are RF equivalent of optical mirage where a city up to 2000 miles away has been seen. The "water" mirage is usually reflected Sky.

I makes for good fun on Radio.

I once got Spanish VHF Tv upstairs on a portable TV with its built in whip in Limerick City (about 14 years ago).

Ulsterman 1690

I used to do a bit of Band 1 TV DXing myself
Spain was the easiest country to get followed by Norway/Denmark/Iceland and Sweden also Portugal. For some unknown reason it was very rare to pick up anything from Central Europe (although I was always reading about other DXers managing it) I think I managed Switzerland and Germany once and an unidentified Eastern Bloc (possibly Czechslovakia) test card and that was about it

During some years one could find Spain almost every day on E2/E3 during May/June (and that was with a simple telescopic or homemade wire aerial) although Im told most (if not all) the Spanish transmitters are gone off Band 1 now

I used to hear a lot of stories about people in parts of Galway Clare and Cork being treated to Bullfighting etc but I wonder what the Spainards made of Derek Davis and Bosco

During a good SpE opening Spanish Italian French or Finnish FM radio radio stations used to come blasting in wiping out local stations (especiallly in the days when there was a lot of Irish pirate stations were using FM studio/tx links) although before the days of affordable RDS it was hard to identify these transmissions

thehurricane

go back to ur loveulster board and stop trying to bring ur bigotry into educated and interesting boards.

Ulsterman 1690

(sigh) Oh dear :rolleyes:

Mossy Monk

thehurricane wrote:

go back to ur loveulster board and stop trying to bring ur bigotry into educated and interesting boards.

who are you?

banned