Q100.5

On the map

Where Q100.5 is radiated from — 5 transmitters [V], Ofcom's published positions. This says nothing about how far the signal reaches; it is not a coverage map.

FM

5 FM transmitters, strongest first. ERP is published per polarisation; a dash means nothing is radiated in that plane.
Transmitter	Nation	Frequency	ERP (H)	ERP (V)	Height	RDS name	PI code	Area
Camlough	Northern Ireland	100.5 MHz	500 W	500 W	30 m	Q_Radio	C781	Newry
Kilkeel	Northern Ireland	101.1 MHz	217 W	217 W	33 m	Q_Radio	C781	Kilkeel
Downpatrick - NI Water	Northern Ireland	100.5 MHz	—	200 W	30 m	Q_Radio	C781	Downpatrick
Armagh - City Hotel	Northern Ireland	107.6 MHz	38 W	150 W	18 m	Q_Radio	C781	Armagh
Tullybrannigan Road	Northern Ireland	101.1 MHz	25 W	100 W	8 m	Q_Radio	C781	Newcastle

Radiation pattern

Camlough publishes the strongest FM signal for this station with a shape on record — where it is carried elsewhere too, this is not necessarily theirs.

Radiates most strongly toward the north-east (50°), as published by Ofcom.

More detail

Each ring is 10 dB of attenuation below the pattern's own peak; the outer rim is the peak itself and anything 30 dB down or deeper is drawn at the centre rather than off the edge of the chart, so a very deep null reads as “weak” and not as a hole in the picture. The shape says which direction radiates harder relative to the mast's own peak, not the absolute field strength there or how far it reaches — that is what the coverage map and the postcode lookup are for. Solid is horizontal polarisation, dashed is vertical.