GTFM

FM · DAB

On the map

Where GTFM is radiated from — 9 transmitters [V], Ofcom's published positions. This says nothing about how far the signal reaches; it is not a coverage map.

FM

4 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
Pontypridd - Bryn Tail	Wales	107.9 MHz	50 W	50 W	14 m	__GTFM__	C781	Pontypridd
Aberdare - Leisure Centre	Wales	107.1 MHz	25 W	25 W	18 m	__GTFM__	C781	Aberdare
Mountain Ash GC	Wales	100.7 MHz	23 W	23 W	15 m	__GTFM__	C781	Mountain Ash
Tonyrefail	Wales	95.7 MHz	10 W	10 W	15 m		C781	Tonyrefail

DAB

The ensembles carrying this station. Every transmitter of an ensemble carries all of its services, so the transmitter list belongs on the ensemble's own page.
Ensemble	Block	EId	Transmitters	Broadcast as	Area
Merthyr Tydfil and Rhondda Cynon Taf small-scale	9A	C224	4	GTFM	Merthyr Tydfil and Rhondda Cynon Taf
Cardiff small-scale	10D	C1E0	3	GTFM	Cardiff

Radiation pattern

Pontypridd - Bryn Tail 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 east (90°), 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.