Other ships, Other transmitters
Although RCA manufactured transmitters such as those on the Ross Revenge were popular among the offshore beat-fleet stations, various other makes were popular too. The second most common was Continental Electronics, used by both the original Caroline ships, Frederica and Mi Amigo, as well as the MV Laissez Faire (Swinging Radio England, Britain Radio) and the second Veronica ship, the MV Norderney. Some of the smaller stations had a variety of mix and match home built transmitters, including some heavily modified sets such as navigation beacons and ship to shore transmitters! As I have researched the transmitter systems as installed on the Ross Revenge, I've also come across information which has established the fate of some of the transmitters from the other offshore stations. This web page goes someway to identifying these sets, and showing the various fates to which they were eventually disposed. The table is by no means complete, and no doubt contains some inaccuracies, so any further info you can shed will be much appreciated. I've also uncovered some remarkable facts pertaining to various transmitters, so if you would like your eyebrows raised, read on! My grateful thanks to everyone who has helped contribute to this list.
The MV Courier "Project Vagabond" was fitted out for use as a floating Voice of America relay station in 1951. For all of its life it served in the Eastern Mediterranean though it was orignally conceived to be able to sail to world troublespots carrying its "cargo of truth". Some reports say it was possibly docked and coupled into a landbased antenna system whilst others say it was moored off the coast of Rhodes in Greece. It carried a helium balloon to hold its own 5/8's inch antenna wire if required - an idea unsuccessfully adopted by Laser 730/558 on the MV Communicator 30 years later. As well as a water cooled RCA BTA-150A 150kw MW TX, it also had a pair of Collins 207-B1 shortwave transmitters and normally received SSB feeds via HF for rebroadcast. This seems to be the first publicised successful attempt at what we would recognise today as "offshore radio", though the ship only broadcast from within territorial waters with the permission of the Government concerned. The signal was widely received, and was heard as far away as Australia. The ship was approximately 5000 tonnes, ie. five times the size of the Ross Revenge and was reportedly manned by a crew of over 100 men. See the articles in the February 2004 edition of "Medium Wave News", and the September 1952 article in "Electronics" magazine for more details.
The largest of these was the 600kW "Aspidistra" transmitter at Crowborough in Sussex, then the largest MW broadcast transmitter in the world and codenamed for the Gracie Fields song "The Biggest Aspidistra in the World". It was operated initially by MI6 then by the Foreign Office.
A number of one kilowatt BTA-1E transmitters were bought by the BBC, and used to cover principal cities when all stations were aligned to the same channel as part of the "Group H" project to prevent enemy bomber direction finding. After the war many of these found use as relays for the new "Third Programme" and in the 1970's they were used for BBC local radio. Several operated until the mid 1980's.
A very large number of RCA ET4336 HF communications transmitters were also procured, firstly for government use but then many were sold as surplus, principally "for export only", though at least 150 sets went to the BBC. These were modified with full bandwidth audio stages (based on a Leak LSM/8A loudspeaker amp) and where necessary, wave-changed to MF and used for many applications such as fixed medium wave relays (some again for the 3rd programme), trailer mounted emergency facilities, and even for early television facilities! See the excellent article by Dave Porter in the March and April 2004 Radio Bygones magazine and the "On Air" (Story of BBC Transmission) book (Shacklady and ??) for more details. It was an ET4336 which was acquired by Radio Invicta on the Red Sands fort and modified for MW broadcast use. The PA stage of the 4336 consisted of a pair of 813's, and had the flexibility of being tunable over the range of 2-20MHz. Versions were built with both VFO and Crystal oscillators.
A number of fifty kilowatt RCA BTA-50E plate modulated transmitters were imported, one going to Aspidistra, and some were later used for the 247 metre (1214kHz) Light Programme "fill ins" such as Moorside Edge and Westerglen.
When built in 1944, the BBC Over Seas Extension number 10 (OSE 10) site at Woofferton in Shropshire was equipped with six fifty kilowatt shortwave transmitters, RCA SW-50, often known as MI-7330. However, they didn't immediately go into service as upon their installation the BBC were "persuaded" to loan them to the government and four were promptly removed and shipped to Crowborough where their high voltage power supplies and RCA 880 water cooled PA triodes were used to provide power for a broadband VHF jamming transmitter intended to block remote radio control of the new German V2 rockets. However, it later transpired that the rockets were not in fact radio controlled, unlike prototypes captured in Sweden and Poland, and the SW-50's were returned to Woofferton where they lived happily ever after until four were removed in 1963, and the final two in 1981.
Now here's an interesting story.
Several years later, the two transmitters are no longer required for Rhodesian coverage, and are taken out of service. Number 13 is shipped to Cyprus where it forms part of a relay for the World Service and will operate until c.1987 when it is sold. Number 12 (the one which should have gone onboard the Mi Amigo) is crated up and returned to the UK where it is installed at Crowborough, the then Foreign Office site in Sussex responsible for BBC World Service broadcasts into Europe on Medium Wave where it acts as a standby for "Aspidistra." A co-located 10kW Marconi Short-wave TX remains in Bechuanaland and is donated to the local government there.
It's now spring 1970. Radio North Sea is broadcasting from the Mebo 2 from the East Coast, much to the dislike of Harold Wilson's government, who for the first time in history, decide to jam broadcasts of a station to prevent British listeners hearing its output. Initially a low power jammer from a naval station at Rochester is used but this is soon replaced by a 10kW transmitter, borrowed from the BBC at Brookmans Park under the agreement that in no way are the BBC to be linked with its use. However, in the run up to the June general election the decision is made to use an even more powerful jamming transmitter. RNI now starts identifying on-air as "Radio Caroline International" and adopting a pro-Conservative campaign and reminding the newly registered to vote 18-21 year olds that it was Harold Wilson's Labour government which closed the offshore stations three years earlier. Quietly and mysteriously, one Continental Electronics type 317C fifty kilowatt transmitter, serial number 12 is removed one night from Crowborough for top secret purposes. All the evidence suggests that this was quickly installed at an old "Chain Home" radar site at Canewdon in Essex, allegedly causing much local TV and radio interference and this transmitter is used to jam RNI during the election week. Following the election, with no immediate sign of the jamming ceasing, the MEBO 2 ups anchor and heads for Scheveningen in Holland, and the jamming stops. Equally mysteriously after the cessation of the jamming, the missing transmitter magically returns to Crowborough and resumes it's former duties. In the late 70's it is once again packed up and shipped, this time to the recently vacated US Over-the-Horizon (OTH) military radar site at Orfordness on the Suffolk coast, which was codenamed "Cobra Mist". Test transmissions carried out from here on 648kHz prove this site is much more effective at mainland European coverage than the existing site at Crowborough and accordingly, plans are made to install new high powered transmitters at Orfordness and the 1930's vintage 600KW RCA transmitter, codenamed "Aspidistra", originally used for propaganda broadcasts to Germany, makes it's last broadcast from Crowborough in 1982 and is dismantled. The 317C remains as standby for much of the 1980's, until in the aftermath of the October 1987 "hurricane" when much of the East Coast is without electricity, the 317 makes a triumphant return to the air. It runs from a generator set for 4 or 5 days whilst national grid power is restored to Orfordness - the generator being incapable of powering the main 500kw sets. As of 2003 the well travelled "with history" Continental Electronics 317C, serial number 12, once destined for use on the Mi Amigo, but diverted to Africa and later used to jam RNI, resides at Orfordness, a mere short nautical distance from the resting place of the Mi Amigo, and is up for sale at a seemingly bargain price.