Sunday, 24 September 2017

The incident at Crowsley Park on the night of 20-21 May 1982

This is one of a series of posts on Radio Atlantico del Surthe Spanish-language shortwave station operated by the British Ministry of Defence in the final four weeks of the April-June 1982 Falklands War. 

This particular post is about a specific technical aspect of RAdS's operations. The question behind this aspect can be put simply:

Radio Atlantico del Sur's studio was in London and its transmitter was on Ascension Island. How then did the signal get from the former to the latter?

(Update in May 2022: This article was written in 2017. The question of the link from London to Ascension has since been fully answered, and is explained at the end of the article. The answer means that much of the discussion in the article is now redundant, but I have left it here as a curiosity!)

Reporting for duty

Late one spring evening in the early 1980s I was driving down a dark and deserted road in rural south Oxfordshire. Completely quiet, it would be easy to forget that I had left my home in a Reading suburb just minutes earlier. I turned left at a crossroads by some farm buildings. The road narrowed to the width of a single vehicle and sloped downwards quite sharply, a reminder that I was on the fringes of the Chiltern Hills. Thick woodland stretched out into the darkness on one side of the road. As it turned upwards again, open country appeared. 

I turned right into the grounds of a private country estate. Had I looked up as I passed between the stone gate posts at the entrance, I might have glimpsed by the light of my headlamps two statues of hell hounds with spears through their mouths – for this ancient estate is said to have been one of the inspirations for Arthur Conan Doyle’s The Hound of the Baskervilles.

Moving up the drive, I passed the turning to the estate’s 18th century mansion house. My destination was a smaller, single-storey modern building in the heart of the park. As I stepped out of my car, eight thousand miles away, at sea in the South Atlantic, British troops were being briefed that in just a few hours they would land on the shores of San Carlos Water.

Quite unaware of that, I walked into the building. 

It was 10.45 p.m. on Thursday 20 May 1982 and I was reporting for duty on the night shift at the BBC Receiving Station, Crowsley Park.

Caversham and Crowsley

BBC Monitoring began life in August 1939 at Wood Norton, near Evesham in Worcestershire. In 1943, the service moved to Caversham Park, on a hillside overlooking the Thames Valley on the outskirts of Reading.

If Caversham Park was its brains, its ears were three miles to the north at Crowsley Park. In a remote and very electrically quiet area, this was ideal for setting up an extensive array of aerials for picking up weak and distant radio stations. The signals received were fed down telephone lines to Caversham to be listened to by hundreds of monitors speaking between them dozens of languages.

In 1974, the BBC's separate receiving station at Tatsfield – on the North Downs near Biggin Hill – closed and its functions were merged with the operation at Crowsley. By 1982, Crowsley was engaged in various tasks including acting as BBC Monitoring's receiving site, being part of the transmission chain for the Voice of America, tracking the occupancy of the shortwave, mediumwave and longwave bands, measuring the exact frequencies of BBC and foreign transmitters, and undertaking ad hoc reception checks for the BBC and other international broadcasters.

The night shift

There would have been around half of dozen of us on duty that night. One was my shift supervisor, who had been my immediate boss since I joined the BBC nine months earlier. A kind and cheerful man, I remember him with affection. He had joined the BBC straight from school (perhaps aged 14 or 15) in 1944 as a so-called Youth-in-Training (YiT).

(All the YiTs were boys. During the war many girls also joined the BBC straight from school, but in BBC-speak they were known as "Technical Assistants (Female)".)

On reporting for duty, the supervisor assigned us to our tasks for the night. I still have my 1982 diary and it tells me that for that night I was assigned to "the scan". Every day we took a small portion of the shortwave spectrum and logged every station we could hear in it. The results were used in the BBC's planning of its shortwave transmission schedule. The scan would also identify anomalies – new stations, ones that we hadn't heard before on that particular frequency, or unexpected gaps.

Listening to Radio Atlantico del Sur

Along with my assigned work, I also had another job in mind for the first part of the shift.

Radio Atlantico del Sur had launched the previous night, and I had listened live to its inaugural broadcast. I was going to be too busy to do that tonight, so I set a tape recorder running on a spare receiver tuned to RAdS's frequency, coming from the requisitioned BBC transmitter on Ascension Island.

I'd be able to listen to the tape at home at my leisure. 

The requisitioned transmitter duly came on the air at five minutes to midnight UK time (2255 GMT), airing Radio Atlantico del Sur's jingle and identification at one-minute intervals. RAdS's programmes then began as scheduled at the top of the hour.

Secret orders

At some point during RAdS's three-hour broadcast, and while I was busy with "the scan", one of my colleagues – who had also been very helpful in training me, and who tonight was sitting in the same room but working on another task – told me that he had heard that our supervisor had been given "secret orders" for that night.

These were to check the shortwave "feeder" transmitter that was being used to relay RAdS's signal from the UK to Ascension.

Our supervisor felt honour-bound not to reveal to us the exact frequency of RAdS's feeder, though he did disclose that it would not be coming from the BBC's Daventry (Northamptonshire) or Rampisham (Dorset) stations – used by the BBC for its own feeds to Ascension – but from British Telecom's radio station at Rugby (Warwickshire).

Rugby Radio Station

The Rugby station did not air public broadcasts, but carried commercial, maritime and military radio traffic.

Built by the Post Office in the 1920s, by the time of the Falklands War it was operated by BT, still in state ownership ahead of privatisation in 1984.

Although best known for its VLF (very low frequency) transmitters and their huge aerials (once a landmark by junction 18 of the M1 motorway), Rugby also had extensive shortwave capabilities. [1]

The hunt for the secret frequency

Although our supervisor had not revealed the frequency of RAdS's feeder, what can be transmitted by one man can be found by another, particularly a Crowsley monitor!

And so my colleague set about trawling the relevant portion of the shortwave band to find it.

He did so in quite a short time. It was on 11420 kHz upper sideband (USB). 

But...

So, we thought the problem had been solved. Just as the BBC used single-sideband (SSB) shortwave feeder transmitters at Daventry (where there were two of them) and Rampisham (just one) to get their programmes to Ascension, so Radio Atlantico del Sur was using Rugby for the same purpose. 

In turn, we could safely assume that Rugby received the signal by a BT circuit from RAdS's London studios.

However, the observations we made are at odds with two published sources, which suggest the use of a satellite link.

A satellite link?

Although Radio Atlantico del Sur's civilian manager, Neil ffrench-Blake, was at home in a radio studio (he had been programme director of a British commercial station in the 1970s) he made very little mention of RAdS's technicalities in his memoirs. On the question of feeding his signal from London to Ascension Island, his somewhat wordy memoirs uncharacteristically touch on the matter only briefly: 

We set up offices in London, near the MoD, and borrowed a set of studio equipment from a friendly radio station. Our broadcasts, which were live, were relayed to the transmitter via satellite by a commercial organisation. That was the main cost, in fact.

So, a very clear statement from a man in a position to know, albeit a statement published 33 years after the event.

A source dating very much closer to the events they describe is the official "Report on Psy Ops in OP CORPORATE". This document, an overall retrospective by the MoD, was written shortly after the 1982 war. (Operation CORPORATE was the British codename for the entire South Atlantic Campaign.)

It was released by the Ministry of Defence to the British National Archives in June 2017. The text of the document and the annexes can be read at Lee Richards' psywar.org website. https://www.psywar.org/

It's a substantial document, though as with ffrench-Blake's memoirs, the question of the studio-to-transmitter link is covered only briefly:

[A] case was submitted on 28 April 1982 under the codeword MOONSHINE to set up RAdS. It was proposed that a BBC transmitter should be taken over in Ascension for the duration of the broadcasts (4 hours daily) and that the broadcasts would be prepared in London and transmitted live (via satellite and land line links to the transmitter).

So another statement that the link was provided by satellite.

Conclusions

So, was there a satellite link? I doubt it. It's possible that the feeder we heard from Rugby was just a belt-and-braces backup for one, but it's more likely that Rugby was the sole link to Ascension.

If a satellite feed had been used there was the question of how it would have been handled at Ascension. The whole set-up at the BBC relay station there was based on the principle of receiving feeds from the UK on shortwave. Receiving a feed via satellite would presumably have involved the Cable and Wireless station on the island (which was quite separate from the BBC facilities) and then feeding the signal from C&W to the BBC site.

Above all, why bother to use a satellite feed when other, perfectly adequate, arrangements were already in place? 

My guess is that ffrench-Blake and his team, with so many other things to arrange in the very short time they had to launch a radio station from scratch, simply asked BT to look after the arrangements for getting the signal to Ascension, and didn't get involved in any of the technical details. The possibility of a satellite link might have been mentioned at the start by one side or the other, but BT would have soon found that a simpler arrangement was available.

As for the MoD's "Report on Psy Ops in OP CORPORATE", the mention of a satellite link comes from when RAdS was still in the proposal stage, rather than subsequent confirmation of what was used.

As it happens, by 1982 international broadcasters were phasing out the practice of using shortwave feeds to their overseas relay stations. The Voice of America had already shifted many of its feeds to satellite by then and the BBC was in the process of doing so. The feeds to the BBC East Mediterranean Relay Station in Cyprus switched to satellite in October 1982. One source says Ascension began using satellite feeds in 1985 while another says the switch took place "in the early 1980s".

So, this interesting footnote to Radio Atlantico del Sur's operations would never have arisen had the Falklands War taken place just a few years later.

Update in May 2022: In a TV documentary aired in April 2022 to mark the 40th anniversary of the war, Radio Atlantico del Sur's chief engineer Jim Warrack said the shortwave link provided by BT from the UK to Ascension was "rubbish". In his words: “The first thing I did after we started was switch the feed to the transmitter using a phone line because it was a far better signal." (The phone line would have used the SAT-1 undersea cable from Portugal to Ascension, with a separate cable running from the UK to Portugal.) 

So, the question has been answered! RAdS initially used the radio link from Rugby to Ascension, but this was soon replaced by a phone link using undersea cables.

Further reading

More details of the BBC's Crowsley Park receiving station can be found on its Wikipedia page

Notes

[1] Rugby's VLF transmissions included those to Royal Navy submarines (only signals at very low frequencies can reach submarines when submerged). HF (high frequency – i.e. shortwave) services from Rugby ended in 2000. VLF services ended in 2007 and the tall masts were demolished that year. See here for further details of Rugby Radio Station.  

© 2017 and 2022. Material may be reproduced if attributed to Chris Greenway and any original source.

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