Combat Net
Radio Equipment

Radio Equipment

Marconi 1.5kW spark Pack Set with Crystal Receiver
WWI Radio Station, 1918

Radio Development

 

At the onset of World War I, radio was still in its infancy. Equipment was primitive and had a very short range. Many of which having limited capacity with only 500-watt peak output power, or the 1500-watt spark transmitters and their crystal detector receivers, both of which significantly impacted by atmospheric interference. An aircraft with a radio, at the time considered cutting-edge equipment, had a maximum range of 2,000 yards.

 

Military radio equipment also used vacuum tubes, which were heavy and bulky. As a result, the equipment was difficult to move on the battlefield, even on mules or horse and wagon, which were still the military’s primary mode of equipment transportation. In addition, radio transmissions were often less reliable than using wired telephones or telegraphs.

 

 

The principal method of communication by the British army, up to late 1917, was by cable for speech and Morse transmission. Initially, a single cable was laid above ground and the earth used as the return. However, the cable was vulnerable to damage by enemy fire and, later, by the passage of tanks across the battlefield. To rectify this insulated cable was buried at ever increasing depth but this didn’t avoid the cable being severed. Very often communication was not possible, particularly when troops were moving rapidly forward or in retreat.

Since then, significant development has been implemented to improve performance, size and portability of Combat Net Radios and their ancillaries. This includes the Larkspur, Clansman, Bowman radios, Voice over IP and Satellite systems.

Larkspur

Larkspur Vehicle FFR
Larkspur C42 VHF vehicle Fit
Larkspur A13 Manpack

Larkspur was the name of a tactical radio system used by
the British Army. Its development started in the late 1940s
and was issued in the mid-1950s. It remained in service until
replaced by Clansman in the late 1970s, although some
elements of Larkspur were still in service into the 1980s. It
was widely exported to British Commonwealth armies and
other friendly nations.
Larkspur began as a post-war project to move tactical
short-range radio communications in the forward battle area,
from HF using amplitude modulation to low-band VHF using
frequency modulation. A similar move by the US Army in the
latter part of World War II had demonstrated significant
advantages. Where it was not practical to use VHF, HF sets
using narrow band phase modulation were developed as the
only practical method of obtaining some performance
improvement over the use of AM or Amplitude Modulation
radio, at that time.
The range of sets originally comprised a number of vehicle
VHF sets, the C13 vehicle HF transceiver and the A13 HF
man-pack transceiver. All were designed to specifications
produced by the Government’s Signals Research and
Development Establishment and officially called the ‘New
Range’ to differentiate them from legacy wartime radios.
They all had similar tuning drills; film strip displays for
frequency indication; a relatively simple architecture that
avoided complex switching where possible; had commonly
available components and a degree of modularity in
construction. All the sets were constructed in strong,
hermetically sealed, alloy enclosures; this was essential to
ensure durability and reliability.
An important operational advance was that the sets could
be accurately pre-set on a frequency without radiating any
signal. This enabled all stations on a net to be confidently
pre-tuned on the same channel and eliminated the old
compromising ‘Tuning and Netting Call’ system that could
give away the presence of a net to an enemy.
Initial roll-out of the VHF New Range sets was restricted
to the Royal Armoured Corps and the Royal Artillery.
Project Larkspur was set up to re-equip the rest of the Army
and the name was retrospectively applied to the original
New Range sets. By common usage it became the generic
title for virtually any radio equipment used by the British
Army between the end of World War II and the arrival of Clansman over 30 years later.

Clansman

Clansman was developed by Signals Research and
Development Establishment in the 1970s, to satisfy the
requirement laid down in 1965. It was built by Racal, MEL
and Plessey and represented a considerable advance over
existing radios in use by Armed Forces at the time. It replaced
the aging Larkspur and was more flexible, reliable and far
lighter. The technological advances achieved in the design of
Clansman allowed the introduction of Single Side Band
operation and Narrow Band Frequency Modulation to
field-level communications for the first time.
Clansman was used by British Forces from the early 1980s,
the first active use was in the Falkland Islands operation in
1982. It was replaced in 2007 by the new digital Bowman
communication system.
The Clansman family consisted of nine main radio units,
three of which were UK/Vehicle Radio Communications
and the remaining six were portable UK/Personal Radio
Communications for a foot soldier.

Fitted For Radio (FFR)

Clansman FFR and manpack deployment

Tactical Communications Wing vehicles were fitted with
Clansman radios to support the rapidly changing Cold War
battlefield. This meant that they could provide tasking nets
and rear link communications to RAF assets supporting
ground forces. The Clansman 35 series were VHF and the
32 series HF radios.

TCW Sat Com and Clansman equipment.
TacATC with PRC113 Radio, Desert Landing Strip

UK/Vehicle Radio Communications 353

A vehicle-mounted VHF FM transceiver. It was also capable

of data transmission and could provide secure speech when
used with a Digital Master Unit. The system was used as a
Command and Control network for ground environments.
Antenna systems provided improved performance.

 

 UK/Vehicle Radio Communications 321

A vehicle-borne HF transmitter/receiver. It was used for
inter-site communications outside of the normal working
range of the VHF forward area nets, and for rear link
communications. The system was used in conjunction
with an Adapter Teleprinter Radio to provide signals traffic
and vital Air Tasking Orders. It could be adapted to avoid
interference with nearby HF Radios or to tune the radio
to the attached antenna.

 

UK/Vehicle Radio Communications 322

A UK/Vehicle Radio Communications 321 station with an
additional amplifier and high power antenna tuning unit.
A tuning unit radio frequency artificially lengthened the
antenna for use with HF wavelengths. Not having to set up
a larger antenna was very useful in a mobile environment,
so the system was often used to provide long haul, rear link
communications.

Radio Equipment

Clansman Radio Equipment

HF Radio Equipment

VHF Radio Equipment

Clansman Ancillary Equipment

Masts and Aerials