Between WW2 and Larkspur
Before the Larkspur Generation begins, there was also a British stop-gap measure with attempts to improve the function and looks of the No. 19 Set. The Hybrid Wireless Set come C-Set was called the C12 (made by Pye UK). It had a frequency range of 1.6 to 10.0 MHz. RF output 5 Watts AM R/T (Voice) and 8 Watts CW (morse). MO control with ability to “hop” between two preset (red and blue) separately tuned channels. The range was about 15 miles. The flick frequency feature was de-coupled and so the Blue and red tuning knobs were now separate and effectively allowed a new frequency to be prepared after a forced frequency change as a new alternative. This was an improved feature of the original 19 set, that before the invention of frequency agility (hopping) in the digital age helped make the set useful for critical EW situations during the cold war years. even the ATU had separate coils for the two frequencies.
The C12 despite looking so different, was however still just a reworked W.S. No. 19 set with some aspects of the later planned Station Radio C13 and C11/R210 Radio
Larkspur Generation Equipment
Receivers
The R-209 covered the 1 to 20 MHz upper-medium and Shortwaves in four bands, and could receive CW, AM R/T and FM R/T. Three versions were made, the earliest for 6V dc vehicles, the second was switchable for 12V and 24V dc and the third version for 12 or 24 V dc or for 115 or 230 V ac mains.
The R210 (Which was mainly used with the C-11 Transmitter) covered the Shortwaves from 2.0 to 16.0 MHz in Seven bands
The R-216 Covered the Upper S/W and VHF Frequencies 20.0 to 155 MHz in Five bands
RADIO SETS and TRANSCEIVERS
The C11/R210 was developed for medium range HF communication and was primarily a “Royal Signals only” set. A complete set comprised four main units: The Transmitter (C11), The Receiver (R210), a Power Supply Unit and the all important Tuner RF Antenna No. 7.
Details of the design of the receiver (R-210) can be found here http://www.qsl.net/vk2dym/radio/r210a.htm
The transmitter and PSU have orange coloured vents that must be opened before the set is used. They however must be closed at all times when not in use especially before fording a river and before the set might otherwise get wet. At the back were larger round orange vents (one on the Tx, one on the PSU), that if forgotten got the user into trouble.
Here a complete set is carried by the carrying frame from a landing craft. The two larger round vents at the back of the Tx and PSU can be clearly seen. The Rx is above the PSU and the ATU on the right (left when seen from the back as here) with a Base Ariel on top of it. The set has a frequency coverage of 2.0 to 16.0 MHz in 3 separate ranges (Tx) and seven bands on the Rx. It is usable for AM (Voice) CW (Morse) and FSK (frequency shift keying). The RF output is 50 watt on high power and 5 to 10 watts on low power.
The positioning of connectors and lengths of the cables and bootstraps are so that the Receiver can be mounted next to the Transmitter in a low row if needed, or be fitted above the Transmitter on the common carrying tray as shown on the Landing craft photo and the coloured “Flag” picture above.
The C13 was a HF set designed to replace the No. 19 set and/or interim C12. It shared a common design with the HF/VHF Sets like the C42 and C45.
It is a medium range HF set, primarily developed for rear communication for vehicular use in forward areas. It can also used as a ground station. The C13 comprises of combined Transmitter Receiver C13, and a 12 or 24 volt PSU (Power Supply Unit) and not shown here, a Tuner RF Antenna No 11. The 12 V suited the FFW jeep and early Champs with FFW 12 V circuits, while 24 V suited the Champ FFR and Land Rover as well as AFV and lorry fitted use. The set and power supply dimensions are identical to those of the C42 and/or C45 and the front panel layout and tune-up methodology kept similar. Despite the common mechanical layout, and sharing same intercom junction boxes and cables, the Power-supply of the C13 or 42 or 45 cannot be used on any other numbered set. The C13 offered AM or phase modulated voice communications, or CW (Morse). The RF output on CW and phase modulation is 20-30 watt, reduced to 10-15 watt with AM due to the higher interference when using amplitude modulation.
C42 versions 1 & 3 use 241 channels from 36 to 60 MHz in 100 kHz steps. C42 version 2 has nearly twice as many (481) channels from 36 to 60 MHz in 50 kHz steps. RF output is 15 to 20W (HP) or 0.5W (LP). MO with an internal Xtal calibrator. FM R/T (voice) . Range is about 10 to15 miles.
Station Radio C42 is a mainly a VHF vehicular GP transceiver primarily for VHF command nets at Corps, Divisional level and also for Territorial Forces and smaller Units.
The C45 is a HF and VHF Set covering the upper short-waves from 23.0 MHz through to 38.0 MHz in the VHF band. A two megahertz overlap with same channel spacing ensured that if needed a C42 could communicate with a C45 such as in disaster relief, Civil defence, NODUF co-ordination, etc. The versions 1 and 3 have 151 channels (in 100 kHz steps), while a version 2 has nearly twice as many, i.e. 301 channels in 50 kHz steps.
The next one is the C-42 but shown with the “Delphi” BID 150 Encryption unit. More about this BID and similar equipment can be found on the Line and Crypto Page
The last one is a really rare set, the HF-49 “J4F” (details of it can be found in the “How2 Radios Page” CLICK HERE)
