It was originally built in 1984 as a fill-in relay for UHF analogue television covering the communities of Penderyn and Hirwaun.

Penderyn transmitter re-radiates the signal received off-air from Carmel about 30 miles (50 km) to the west.

After the switchover process, analogue channels had ceased broadcasting permanently and the Freeview digital TV services were radiated at an ERP of 2.6 W each.

[1] Penderyn entered service in spring 1984,[2] and (being in Wales) transmitted the S4C variant of Channel 4.

The UK's digital switchover commenced at Carmel (and therefore at Penderyn and all its other relays) on 26 August 2009.