Fitted For Wireless

Fitted For Wireless (FFW) and Fitted For Radio (FFR) were British Army designators for vehicles equipped to carry radio equipment. Although many of these vehicles would be dedicated 'radio vans' and would have the complex and expensive radio sets installed, the intention was also that general purpose vehicles could be issued in 'FFW' state with the low-cost but time-consuming cabling and equipment mounts already prepared. The actual sets themselves could be installed later, if a new radio vehicle was required owing to damage or breakdown.

'Wireless' is a period term for 'radio', particularly in British use. The two 'Fitted For ...' terms had distinct, but not obvious, uses in this particular context and are often confused.

FFW was the first term to be used and was applied to radio vehicles during World War II. Vehicle mounted wireless equipment early in the war was typically the Wireless Set No. 9 or No. 11, but after introduction in 1941, the No. 19 quickly became the standard set. This was a large, heavy, valve set, requiring a large power supply from heavy lead-acid batteries. A typical radio vehicle at this period would be a Bedford MW light truck of 8cwt or 15cwt capacity. In its FFW configuration, this might be equipped with two No. 19 sets, one low-power operating alone and one high-power set equipped with an additional Amplifier RF No. 2. These sets were arranged on a fitted desk across the body of the truck, with four or eight 6 V lead-acid batteries beneath.

Wartime sets generally required a 6 V or 12 V supply, and batteries were charged by a small petrol-engined charging set (generator) of 300 W, often the 'Chorehorse' type. When in use, this generator was carried out of the vehicle on a carrying frame and placed on the ground outside. The vehicle's own engine and lighting batteries were separate. Some vehicles were fitted with additional radio charging dynamos driven from a gearbox PTO. Later in the war, 24 V vehicles began to appear, firstly US-supplied armoured vehicles, further complicating the wireless supply considerations. In the case of the 19 set, a composite power supply that allowed 12 V, two-wire 24 V and 3-wire (i.e. 0 - 12 - 24 V) systems was introduced. This power supply also contained a vibrator type HT section so that the receiver section of the set could be run more economically.

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