WW2 and Before Generation Equipment
The standard set of the Long-Range-Desert-Patrol in North Africa, the No. 11 was a portable transceiver developed in 1938. It was designed as a general purpose low power short distance set, to be used as a static station, or on a horse or mule, and most importantly as a mobile vehicle mounted station .
Frequency range 4.2-7.5MHz. MO control. RF output 0.6-4.5W. R/T and CW. Range was only up to 20 miles and less on dry sand, but despite this the LRGP (LRDG) discovered when propagation was best and managed hundreds of miles via sky-wave skips.
The set as seen above would be mounted onto two wooden rechargeable battery boxes and into the back of a Morris CS8 or Chevrolet 15 Cwt light truck. In the middle was a Watch holder, a common feature on British radio sets once the boffins worked out the watch needed a Anti-magnetic back if it were used next to a radio transmitter or power supply. The WS No. 11 was a very successful design, but too costly and time consuming to build. It was soon superseded by the wireless sets No. 19 and No. 22.
Based on a No- 8 set a portable man pack for short range communication, comprising of separate transmitter/receiver in a common case with battery compartment in the bottom. It was developed in 1940, and used in forward areas between Battalion HQ and Company HQ.
The frequency range was 6 to 9 MHz. MO control. Despite having a RF output of only 0.25 Watts in R/T or CW mode, it was capable of ranges up to 10 miles. In 1942 the WS No. 18 was “re-developed” by the USA as the No. 48 set.
Later (in 1943) the No. 68 Set (which is similar but with different frequency range of 3.0 to 5.2 MHz and 1.75 to 2.9 MHz as WS 68”P” model) came out. It also had a Xtal control option.
WW2 Microwave (4 GHz).
The Wireless set No. 10 is a Trailer with two generator sleds, racks of 4 GHz equipment and a pair of Microwave parabolic dishes on the roof. There were only 100 complete sets made allowing for 50 point to point microwave links. Using Time Division Multiplex (an early form of digital transmission still used today in telecommunication circuits) eight full duplex (two way) telephone lines could be provided via each directional “Line of sight” microwave link. The power was only half a watt, but it could span link distances of 50 miles. For very long links seven radio relay stations could be inserted (each needing two WS 10 trailers to catch the link and send it on to the next leg). Thus a very long link could use up to sixteen trailer mounted sets.
With the exception of four prototypes on a reversed chassis, the entrance to the trailer for the station was via a door over the drawbar at the front. The sides could be folded down or removed (as seen above). In the vehicles section (1939-1945) a copy of this drawing with the sides in place can be found When the rear section was folded down, the generators could be drawn out (they are mounted on sleds) to be exchanged or serviced. By using two such generators it was possible to keep the link going while one was being repaired, serviced or swapped out.
The station was contained in a 4 wheel 2 ton trailer and used within a month of the D-Day landings in July 1944 to support the advance of 21 Army Group in their advance across Europe. 'Monty' called it his 'Number 10 Thingy'.
Here a mountain-top relay station with three WS No. 10 trailers during the advance into Germany. (The invasion of Mickey Mouse Radio) The UK station was on Ventnor Hill (close to the site of the Long chain Radar that had helped detect German aircraft during the battle of Britain. The path over the English channel to Cherbourg was 70 miles. In 1931 the French company LMT and makers of the 1910 French designed “M” set (M for Military) Mounted Wireless set mentioned above, together with the British STC set up the first experimental microwave link across the English Channel. Marconi had already made and used a similar microwave link in the late 1920s and made a microwave telephone link between the Vatican and the Pope’s summer residence in castle Gandolfo in 1932, (and accidently discovered radar) but even that was “old hat” as the Inventor Dr. Jagadis Chunder Bose had not only invented Microwave Radio and semi-conductor technologies, but made working models of remote doorbells and radio triggered EODs (mines) which he demonstrated in the 1880s in India and 1890s in England... His first Microwave Radio system (up to SHF frequencies of 8 GHz) was invented in 1880s and later improved with versions at 60 GHz that he successfully presented in 1895 to the Royal Society. He also invented and used waveguides, horn antennas, dielectric lenses, various polarizers including circular polarizers and even field effect junction semiconductors all for use at frequencies as high as 60 GHz; much of his original equipment is still in existence, now at the Bose Institute in Calcutta. Marconi was starting (like most radio engineers of the time) at Very Long Wave frequencies and slowly working up towards Microwaves, but Bose who was not interested in radio, but photosynthesis and light, had started at ultraviolet and was working his way down into x-rays, radar and radio frequencies. Bradshaw's Railway Timetable played a major part in this new technology. See this page for more info about him and his technology Although he failed to find a real practical use for his microwave Invisible light Dr. Bose invented what today is the mainstay of point to point telecommunications, and invented the Transistor (made a PNP device), prisimic wedge filters, wave tubes, travelling wave tube amplifiers, and microwave dishes and antennea that later were re-"invented" and are used so extensivly especially in satellites, communication and broadcast link technologies today.
He also invented, a full year before Marconi invented wireless, and demonstrated radio controlled bombs and defence systems, a remote controlled bell, etc., and also proved that plants were affected by radio waves, light and touch, and responded to sound...
Quote:
While Marconi in Bologna was still trying to transmit electric signals through space without wires, a race he was to win officially against similar efforts by Lodge in England, Muirhead in the United States, and Popov in Russia, Bose had already succeeded. In 1895, the year before Marconi's patent was issued, at a meeting in the Calcutta town hall, presided over by Sir Alexander Mackenzie, the lieutenant governor of Bengal, Bose transmitted electric waves from the lecture hall through three intervening walls and Mackenzie's portly body to a room seventy-five feet away, where they tripped a relay which threw a heavy iron ball, fired off a pistol, and blew up a small mine.
End-Quote:
Source: http://perso.wanadoo.es/paspas/x/iplant06.html and the IEEE
More surprising “Earlier than you thought” stories can be found HERE
Back to more “Modern” Shortwaves and Valve technologies of WW2.
The 19 Set, its Brothers and Sisters and Off-spawn
This 19 set has the Armoured Vehicle “cage” fitted to stop it being “Adjusted” accidently by the crew of a tank or kit falling onto it while traversing over rough terrain, or clambering in or out. Also as equally important so it’s knobs and switches are not damaged. They were also fitted in many other tight space, applications, not only tanks. The 19, 22, 62, ZC-1 and C12 sets (all based on the 19 set principle) contained a quick “flick” tune system. The dials had four screws in the middle (two red, two blue) which could be set for two different frequencies. Additional adjustments above the transmitter and receiver dials ensured the matching was better for whichever frequency was chosen. Two aerial connectors also ensured the correct matched antenna was connected to the set for the desired first or second frequency. In some cases this was used to Jump frequency if and when the current one used was being jammed, but in most cases was used to set a daytime and night-time frequency for the different atmospheric conditions present. In this example it is a Canadian made version and has dual language markings on the front face, not “English & French” as some might expect for Canadians, but English and Russian, then most of their production was for us and our allies.
Wireless Set No. 19 was only designed as a mobile transceiver developed in 1941 as a quicker and cheaper to produce replacement for the No. 11 set. Initially developed for use in AFVs it was later also used as general purpose set in jeep and truck stations and fixed location ground stations.
The similar looking No. 22 set was made to also be man-portable and offer more scope than the 19 set, but when D_Day came a shortage of No. 22 sets meant that the No. 19 sets needed to be made semi portable for infantry use by putting them onto barrows. Here the Pram mounted versions for infantry use such as during D-day Landings. Lead acid batteries and the aerial mast, spares, etc could all be “Carried” in this way into battle.
The 19 set had MO control and could be used for R/T (voice), MCW, CW (Morse). Frequency ranges were as follows, the 'A' set 2.0 to 8.0 MHz for HF (Shortwave) RF output 2.5 to 9.0 W. Range up to 15 miles and with the RF Amplifier No. 2 increases the ground-wave range to about 45 miles.
The VHF 'B' set version of the No.19 set covered 229-241 MHz, but worked only Three-quarter’s of a mile. It was intended to allow tanks in a convoy to talk to each other without the enemy being able to intercept them or even know they were coming. The deliberate contact only with who you can see, also made them quite suited to co-ordinating air-drop supplies between land forces and aircraft or for arranging the setting down of spies or picking up escaped POWs behind enemy lines.
Wireless Set No. 22 was a portable transceiver based on the 19 set. It was developed in 1942 as a general purpose low power vehicle and ground station with facilities to use it as a man pack. It had it’s own self-contained ATU allowing it to be used with almost any type of antenna. Frequency range was 2.0 to 8.0 MHz. MO control. RF output 1.5W. for R/T (voice) or CW (morse). Range was up to 20 miles.
The Wireless Set No. 62 was a portable/mobile transceiver developed at the end of the War. It was lighter than the No.22 and tropically sealed. It was also water-tight and would swim if thrown into the water (from lessons learned with radio operators drowning while river wading in Far East jungle warfare or during the Scilly and D-Day landings). Unlike the 19 set and 22 set, it had a single frequency dial for both transmit and receive and needed less adjustment for the “flick” frequencies. Like the 19 set and No. 22 set, it was a general purpose for vehicle and ground station, but very suitable as a man pack and animal pack. Frequency range 1.6-12MHz. The RF output was 1 Watt. MO and crystal control. R/T and CW. Range up to 25 miles.
CANADIAN, USA, AUSTRALIAN AND NEW ZEALAND Wireless Sets for the UK
During WW2 The Canadians made many 19 and 22 sets, in fact most of the range of British Radio sets were made also as identical copies in Canada. Some sets were made in the USA by daughter companies of British and Canadian companies. Australia made their own Radio Sets that I will deal with later.
New Zealand made a few sets too, but their copy of the 19 set deserves a special place, the set runs directly from 12 V dc, and in this example there is an additional AC mains to 12 V dc power supply unit for stationary use. The ZC-1 was used by Allied troops (including the Royal Signals) all over the world, some even in Europe and North Africa. But many were lost and today it
is a very rare piece of radio history that is seldom found. Most of the sets that survived their transport ships being sunk on the way to the UK or Egypt, were sold off shortly after the end of the war for less than four Guineas. Some were given to the Civil Defence, Fire Brigades and Police forces for Mobile Radio use. The Greek Army were also donated many thousand sets towards the end of the war.
They also made their own High Power Amplifier seen here “stacked” on top of the ZC-1
