The four masts are a highly directional array, radiating the signal in a tight pattern west across Manchester. The transmitter input power is around 350 watts, and the directional gain of the aerials produces 1.5 kW EMRP in the direction of maximum power (250 deg) on 1152 kHz.
The IBA built such highly directional aerials to avoid interference to other ILR stations using the same frequency. In the case of 1152 kHz, directional aerials were installed by the IBA at Langley Mill (Birmingham), Saffron Green (Barnet, Herts. for London), Greenside (Newcastle) and Dechmont Hill (Glasgow).
The then BBC 'Ashton Moss' site can just be seen in the background of this picture, the three towers, slightly to the south west of the IBA site. At this time it transmitted BBC Radio Manchester on 1458 kHz with a power of 5kW, though this site is now used by the Independent Radio Station Capital Gold |
