Early radio notes
Tom:
The photo caption in your telephone history series is, despite it coming directly out of a book, incorrect. The large electronic tube is not the single "500 kilowatt valve." It was one of FIFTY-FOUR ten kilowatt tubes operable in parallel to form the transmitter at Hillmorton, near Rugby, in England. When I finish this note, I'll try to find the web link to a local web page from there that has some of the description of the site. That plant exists today and is still on the air, its 8 towers of 800 odd feet being visible for miles around.
The giant transmitter is actually ten radio amplifiers of 100 kilowatts input, 54 kilowatts output each. That, if used together, is called by some one million Watts, based on input; by others, 500 kilowatts or 540 kilowatts based on output. In fact, other than for initial testing, all ten amplifiers were never tied together. Nine of them are used in parallel, excited from a source of the Very Low Frequency of 16.7 kilohertz. with the callsign GBR - which might stand for Great Britain Radio or Great Britain Rugby, or some ways in England say, "Great Bloody Radio."
The original purpose of GBR was to be able to send a telegraphic message to anywhere in the old British Empire at any day or time. It evolved into marine radio use, and since the Cold War, has been used to transmit telegraph to England's nuclear submarines, in the same way the US Navy has several VLF stations for the US subs. The tenth 100 kw in/54 kw out amplifier was the bit used for that first transatlantic radiotelephone link in 1927. It was excited at 60 kilohertz with a single sideband speech exciter to work with its AT&T mate in the States. The AT&T reciever ultimately wound up at Houlton, Maine (which was used in later years as AT&T's Telstar satellite station site), and the Deal Beach transmitter on 55 kilohertz was ultimately replaced with one at RCA's huge transmtting plant at Rocky Point, Long Island. The callsign for the British end was GBT, obviously for Great Britain Telephone or such. Speaking of the first transatlantic radio-telephone link, let me mention a few things.
Despite the Bell Laboratories Record account, Deal Beach, New Jersey was merely a Labs testing place, for things like the WWI trials to Europe and such. The actual 55 kHz SSB transmitter for that 1927 London-NY radio link was in the RCA transmitter plant at Rocky Point, way out on the tip of Long Island, 150 miles east of the NYC metro area.
AT&T contracted out the construction and operation of the Rocky Point transmitter throughout its entire life, which was from 1927 until around 1970.
Similarly, I've just received info from some local people in Maine whose knowledge that RCA built a LF receiving station in Maine in WWI (which is probably where Harold Beverage got his start) leads to the likelihood that RCA also built AT&T's receiving station at nearby Houlton, Maine.
In other words the entire US end of the fabled 1927 first transatlantic telephone link was probably built for AT&T by RCA! (After all, AT&T owned 25% of RCA in its early years!). But back to somewhat modern times, at least for a few paragraphs :-)
When HF (shortwave) radio came into practical use, the VLF link was primarily used as the "backup." Even when the first submarine telephone cable was laid across the Atlantic in 1957, the several shortwave links were retired, but the Rugby-Rocky Point pair were actually kept on the air (but idle) as the final backup - actually in case of nuclear attack that would potentially make render both cables and shortwave useless. It wasn't till there were several cables and satellites in use that the 60 kHz/55 kHz link was retired. In England, the 60 kHz operation's callsign was changed to MSF, and it became England's standard time and frequency reference transmitter, which it is to this day. Over the years, the 1927 transmitters have certainly been replaced, but the British Post Office maintains a security cloak over what the GBR transmitter is today. They have told that the MSF transmitter has been replaced a couple of times, and we can certainly expect similar change has been made to GBR. Here's the web page, which isn't that well written, for GBR.
http://62.32.51.17:8033/Radio_masts/ (external link, now having problems)
There's a whole lot more to the early days of telecommunications. I have written a number of vignettes of the monsters of early radio, which I call "Jurassic Telecommunications." By and large, like the dinosaurs, it grew from cricket chirps into beasts of 100 or even 300 kilowatts, and the final bit were a few megawatt monsters like GBR.
One of the more interesting ones is the French megawatt spark monster that Blackjack Pershing ordered in WWI, at a Bordeaux location called Croix d'Hins. It was intended as a backup link across the Atlantic in case the Germans cut the transatlantic telegraph cables. Its callsign was merely LY and operated on VLF of 12.7 kHz. It didn't last long after the war, because when radio began to develop, it was found to cause so much interference that it had to be abandoned! Here's a page about it:
http://www.u-e-f.net/uef-histoire/croixhins.htm (external link, now dead)
There's a LOT of French history with further links at:
http://www.u-e-f.net/uef-histoire/index.htm (external link, now dead)
And, here are a couple of links about a third monster, Alexanderson's Alternator, of which one plant is still maintained at Grimeton, Sweden, callsign SAQ on 17.2 kHz:
http://www.telemuseum.se/historia/alex/1.html
http://www.telemuseum.se/grimeton/defaulte.html
(Both liinks now dead)
There were (and indeed, still are) many "footprints of the dinosaurs" of radio among us. Just last month, I was in Florida finding the concrete tower base of the first - ever AM broadcast "directional antenna" in the world. I hope you find all this interesting. I add to the database as I can. You can see some of it in the Archives section of: http://www.oldradio.com (external link)