Introduction by Dave Porter G4OYX:
Ian JD Anderson is a broadcaster and company secretary and part owner, with his wife Inga, of the Shetland Islands Broadcasting Company (SIBC). Ian read the Tricks of the Trade article in Signal [1] where elevated earth mats where mentioned. This prompted him to contact G4OYX and send a full description of the earth system employed for the former Faroe Islands MF transmitter site. Ian had paid a visit in 1987 to the homeland of his wife Inga. She is 15 generations away from leaving Faroe, where all the rest of her relations have now died out, but her family is thriving in Shetland. The following is Ian Anderson’s report on the site visit.
Overview
The Úvarp Føroya Manager, NJ Arge and a producer, Tróndur Djurhhuus showed us around the radio station. Tróndur also arranged a visit to the transmitters. This was more difficult than may seem, since the transmitters are operated by different divisions of the government than the radio station. The medium wave site is operated by the Telegraphs Department and the FM and TV sites by the Telephones Department. It took some time but arrangements were made and a message to that effect awaited us on our return to the hotel later that day after our visit to Inga's ancestral home of Nólsoy.
MF transmitter
Figure 1. Long-time engineer Vagn Erik Michelsen with the Marconi 5 kW MF transmitter from 1956 but of a design dating from 1941
The MF transmitter site has remained mostly unaltered for 30 years. The transmitter is an elderly Marconi design, capable of around 5 kW. When it is on air, the electricity meter whisks around at a rate of 27 units an hour! It is definitely in its last year or two with the last set of output valves, specially made by Marconi, now resting in the corner of the transmitter building. The transmitter site is on the road out of Torshavn near Hotel Borg. This is the ship-to-shore LF/MF/HF site with about ten antennas held up by detuned lattice masts. The main Úvarp Føroya antenna is slung between one of those and a wooden mast with the spreader cables for the top loading wires attached to further masts. The antenna consists of a fairly short vertical element (four wires), possibly about 25 metres high at most, with eight top wires, four connected directly to the verticals. An open-wire feed line is carried on poles from the transmitter hut to the tuning hut. For the earthing system, the ground is stony and unsuitable for (under)ground radials. Instead, about ten radials mounted on poles are stretched out in an uneven pattern (which must affect the directivity of the antenna but no one knew if measurements had ever been made). The entire system is not capable of a high level of modulation and the Telegraph Department is usually happy with about 30%.
The replacement transmitter is most likely to be a 200 kW AEG-Telefunken and the aerial will be a base-fed quarter wavelength radiator 141 metres high. The transmitter type and site (in Suðuroy) is still a "state secret” but we guess the site is in the high, but soft, ground near the centre of the island just north of Vagur. The new transmitter will be run by the Telephones Department (TFL). The choice of the 200 kW, as approved on the 1978 Geneva Plan, seems to have been made by the Government against some professional advice. Some preferred a modest-powered replacement to cover the islands and thus keep capital and running costs down and others preferred something like two 50 kW Marconi. However, the Government wished to take up the full allocated 200 kW and use it to broadcast as far south as Ireland and Scotland, although potential programming remains a mystery. Certainly, the cost to Úvarp Føroya of the present transmitter, a bargain at £600 a year, will have to increase if only to pay the £200,000 a year electricity bill for the new transmitter. We must thank a wonderful character, Vagn Erik Michelsen, the MF transmitter engineer for its entire life, for kindly showing us around and telling us the most wonderful stories. Figures 1,2 and 3 show pictures of the long-gone Úvarp Føroya site outside Tórshavn, all taken in August 1987.
Figure 3. General view of Tórshavn site with transmitter building feed point right, tuning hut in distance, FM radio and TV mast at Húsareyn in far distance
Akraberg Transmitter
The new 531 kHz MF site at Akraberg, eventually opened in the early 1990s. It has a 147-metre single-mast radiator. From 2006, the transmitters are a 100 kW Thomson (83 kW DRM) and a 50 kW Thomson standby, now on possibly 5 kW though it is listed in the World Radio and TV Handbook at 10 kW and now can hardly be heard on normal radios on the east side of Shetland. There is no information on the present earthing system and as to whether they experienced the lack of a decent ground area due to the terrain. Issue 75 During test transmissions in 2006, all beacons below 500 kHz were wiped out. The author had to liaise between Thomson, UK authorities and the notoriously uncommunicative Faroese. There is FM radio and TV in the Faroe Islands but these facilities are not covered in this article.
Reference 1. D Porter G4OYX. Tricks of the Trade. Signal 2025, 74 (February), 34−40