Saorview geographical coverage map

mrblack

Does anyone else think its curious to see from the saorview coverage map that the coasts are really well served with masts and poresumably coverage-while the unlucky citizens in the inland counties of Offaly to Westmeath seem rather less well served by transmitters.

Is this due to favourable topography allowing further signal travel, or is is just that the population of these areas doesn't merit much investment in transmitters. I have saorview reception problems myself and I live a few miles south east of Navan.

Mrblack

MarkK

Looks to me that Donegal, Mayo, Kerry and Wicklow have the most 'white bits' on the coverage map.

Peter Rhea

A high powered transmitter like Cairn Hill, Clermont Carn or Mt. Leinster can cover a lot of ground provided nothing gets in the way, as would be the case in most of the midlands.

coylemj

You haven't made any allowance for the power of the transmitters. Cairn Hill in Co. Longford at 800 kW is the most powerful transmitter in the country and as the Irish midlands are relatively flat, it services a huge area in the centre of the country, all the way from parts of Co. Monaghan to Laois and North Tipp.

The 'unlucky' citizens of the midlands such as the people in Athlone 45 kms away can pick up Cairn Hill with a bog-standard contract aerial.

The Cush

coylemj wrote: »

You haven't made any allowance for the power of the transmitters. Cairn Hill in Co. Longford at 800 kW is the most powerful transmitter in the country

Cairn Hill is 800kW for analogue, down to 160kW for DTT. After ASO Mullaghanish will be the most powerful transmitter at 200kW.

watty

mrblack wrote: »

Is this due to favourable topography allowing further signal travel

Donegal or Kerry would EACH need about 100 transmitters to get the coverage the midlands have. TV signals don't go through hills, never mind mountains. Ireland is like a bowl. Most of the "tricky" bits are around the edges.

Kurz

coylemj wrote: »

You haven't made any allowance for the power of the transmitters. Cairn Hill in Co. Longford at 800 kW is the most powerful transmitter in the country and as the Irish midlands are relatively flat, it services a huge area in the centre of the country, all the way from parts of Co. Monaghan to Laois and North Tipp.

The 'unlucky' citizens of the midlands such as the people in Athlone 45 kms away can pick up Cairn Hill with a bog-standard contract aerial.

I'm in Athlone and I pick it up with a little cheap ten year old bunny ear aeriel that's sat on the window sil. Never had any problems.

coylemj

Looking at the league table of the highest point in each of the 32 counties, obviously Kerry is #1 with Carrantuohil but if you look at the list from the bottom up this is what you get ....

32 Westmeath
31 Meath
30 Longford
29 Monaghan
28 Kildare
27 Roscommon
26 Kilkenny
24 Laois
24 Offaly

So it's pretty clear that transmitting a TV signal to the midlands only requires one big transmitter in the right place.

http://en.wikipedia.org/wiki/List_of_Irish_counties_by_highest_point

Laois and Offaly are joint 24th because the highest point in both counties is a mountain in the Slieve Bloom mountains who's summit is on the border between the two counties.

No prizes for guessing that the highest point in Co. Longford is the same Cairn Hill.

mrblack

Hi Watty, Cush and Coylemj,

The bowl description says it all and the mast power wasn't something I had thought of either.

There are trees in the way of Clermont Carn for me, a hill to the south blocking Kippure, and Carn Hill is 50kms away based on the coverage map. So I am a bit unlucky even though I am in a supposedly strong reception area. My mother in law lives just 200 metres away from us but on the far side of those blooming trees and she does indeed have excellent 98% quality saorview signal from an aerial mounted in the attic which peeves me off slightly.

After ASO if Clermont Carns power boost doesn't overcome the trees then I will sharpen my chainsaw for some surgery :pac:

watty wrote: »

TV signals don't go through hills, never mind mountains. Ireland is like a bowl. Most of the "tricky" bits are around the edges.

Sponge Bob

You can chainsaw a tree MrBlack, I would suggest that a chainsaw works less efficiently on granite.

Ronnie Raygun

mrblack wrote: »

After ASO if Clermont Carns power boost doesn't overcome the trees then I will sharpen my chainsaw for some surgery

Power increases are unlikely to solve tree problems at UHF frequencies, as the effects are very unpredictable, with trees moving in the wind, getting wet & changing due to growth. You might get lucky though (for a while anyway).

I think you've twigged(!) it, but removing or otherwise taking the trees out of the equation is the only guaranteed solution.

Also, Cairn Hill is about 50 miles from your location. Which coverage map gives distance to the transmitter?