Category Archives: Radio

Bowman Man-Pack Data Terminal Carrying Case

The modern battlefield is now full of electronic devices, with specialist radios, computers and tablet computers in use. These differ considerably from their civilian counterparts, being far more rugged than the relatively delicate mobile phones and IPads we are used to. The British Army use a system called ‘Bowman’ which in addition to having individual and unit radio systems, also has battlefield tablet computers called ‘LTDTs’ and a light weight man-pack data terminal produced by a company called L-3 Communications, called an ‘LMDT’:imageThe Army’s website describes Bowman as:

BOWMAN exploits the latest developments in radio and computer technology to meet the needs for services well into the 21st century.

Designed to provide an integrated digital communications network interfacing with higher level systems and networks such as ISDN, Skynet V,Cormorant and FALCON.

Commanders at all levels are given secure voice and data communications as well as an integrated Global Positioning System (GPS).

Tonight we are looking at the carrying case for one of the LMDTs:imageThis is made of DPM camouflaged Cordua nylon, and is fitted with a large belt loop on the rear to allow it to be attached to a webbing set:imageA small handle is fitted to the top of the case:imageA heavy duty shoulder strap is fitted, securing at two points on each side of the case:imageA heavily padded section is attached to make the LMDT more comfortable to carry (presumably it is a fairly heavy bit of kit!):imageThe front of the case opens up, it is secured with two black plastic Fastex fasteners:imageUnderneath this are a further pair of velcroed flaps that add protection to the screen of the LMDT when it is stowed away:imageFinally when the case is fully opened up it looks like this:imageTwo elasticated straps help hold the LMDT secure, even when the case is open. NSN details are printed on the underside of the top flap:imageThis is a beautifully well made case, and clearly very carefully designed, with openings and flap[s all over to protect the instrument, whilst still allowing it to be easily used. At this stage it seems unlikely I will find an LMDT to fit inside the case any time soon, but these things have a habit of appearing on the surplus market in due course as equipment is upgraded so perhaps something for the future…


DPM PRR Radio Pouch

One of the most radical changes to military operations in the last ten to fifteen years has been in the area of personal communications on the battlefield. Today soldiers each have a ‘PRR’ or Personal Role Radio, which allows them secure and quick communication between members of a section on the battlefield. Up until very recently troops had been forced to use whistles or hand signals. The PRR consists of a small headset and microphone that the user wears beneath their helmet and a small receiver and transmitter unit that is normally worn high on the chest, by one shoulder. This transmitter/receiver is carried in a small pouch that holds it securely in place whilst still allowing the operator to access the controls:imageThis pouch is made of a lightweight, but very strong Cordua nylon. Down the side of the pouch are a pair of openings that allow manipulation of the radio’s controls:imageAn elasticated strap is fitted to the top, with a press stud, to secure the PRR into the pouch so it does not risk bouncing out when the soldier runs:imageA pair of adjustable straps with Fastex fasteners are fitted to one side of the pouch:imageIn service these are passed around the back of the pouch, around the shoulder strap of the soldier’s webbing and back to the front to fasten and secure the radio pouch:prr-radio-pouch-british-dpm-bowman_1_1be3896179d1e205df1c22ada38d6a25The label on this pouch is very small and has no more information than an NSN number and the pouch’s use:imageThese radios are part of the troubled ‘Bowman’ system and the MOD ordered 45,000 of them in the late 1990s/ early 2000s. The British Army website gives the official position:

The Personal Role Radio (PRR) is a small transmitter-receiver that allows infantry soldiers to communicate over short distances.

Effective even through thick cover or the walls of buildings, PRR enables section commanders to react quickly and efficiently to rapidly changing situations, including contact with the enemy, greatly increasing the effectiveness of infantry fire teams.

PRR is issued to every member of an eight-strong infantry section.

The system is easy to use through its simple man-machine interface, is unobtrusive and comfortable to wear yet is rugged enough to sustain the harshest environments.

The use of PRR has significantly enhanced combat effectiveness by providing all informed communications to front line soldiers, replacing traditional methods based on shouting and hand signals.original-dpm-pouch-headband-set_360_8b4cc8609a8b25976ff43944c663f359

No 19 Set Morse Key

There were many variations of the humble Morse code key in use by the British during the Second World War; some sources identify up to a hundred different variations. Tonight though we are looking at just one of these, a little Bakelite example:imageThese little keys were used by signallers to tap out messages in Morse code and were normally wired up to a wireless set, which then sent out the dots and dashes as a wireless signal. Alternatively the key could be wired to a signal lamp, more on that in a few days! Examples could be made of brass, Bakelite, silver alloy or sometimes a combination of materials. This example is made of very robust brown Bakelite. It consists of a base and a spring loaded rocker arm with a large Bakelite knob at one end:imageThe base of the key has a stores code marked on it:imageIn this case it is marked ZA16929, and according to the Imperial War Museum’s online database this indicates the key was used with the Wireless Set Number 19. A second marking at the end of the key reads ‘Key WT 8 Amp No2 MK III’:imageThe key works by completing or breaking a circuit every time the knob is pressed down. Normally the connectors nearest the knob are broken and the ones furthest away are connected, pressing down on the knob reverses that position:imageThis gives a great deal of flexibility allowing the key to be used regardless of how a wireless transmitter is wired- just attach the wires from the transmitter to the relevant connectors on the key.

Rod Balkham describes how he learnt Morse:

Over a period of what must have been several months I was turned into an OWL B3 – that is, Operator Wireless and Line (B3 being rated higher than B2, I seem to recall). This transmogrification was achieved mainly by the challenge of competition, plus – in my case in particular – my instinctive reaction to the sensitive understanding of the corporal who was our teacher. Unlike many another army corporal, he commanded respect in a firm but kindly manner, and he knew his job. As with the Bren gun, I became proficient with the Morse key without having to try very hard. To help us learn the Morse Code, the corporal offered us a few mnemonics, based on the rhythm of the dots and dashes. One was ‘Here comes the Bride’ – you can think of the bride as the Queen, he told us – thus arriving at dah dah dit dah for the letter ‘Q’. Another one, which I have good cause never to forget, was ‘Did-it ‘urt cher?’: Dit dit dah dit for the letter ‘F’, followed, inevitably, by ‘Like ‘ell it did’ for ‘L’.

Wartime Signals Satchel Number 1

As regular readers will know I have been picking up bits of kit for my WS38 set radio slowly over the last couple of years. This week I was very pleased to pick up a wartime signals satchel to go with the set:imageI have previously looked at an example of a signals satchel here, but that example was a post war version in green canvas with white metal fittings. This example is the correct one for wartime use and will go nicely with the radio. This is officially a ‘Signals Satchel No 1’, had a stores code of ZA 6292 and was introduced on 27th May 1938. The main body of the satchel is made from pre-shrunk woven cotton webbing, with a box lid:imageThe lid is secured with a single strap and brass buckle to secure it:imageThe inside of the satchel is lined with cotton-drill fabric to help protect the contents:imageTwo variations of the signals satchel can be found, one with the shoulder strap sewn to the satchel itself, and the more common variety such as this one that has a standard 37-pattern shoulder brace secured with brass buckles:imageThe top of the satchel is printed with ‘SATCHEL SIGNALS’:imageThe inside of the top lid is clearly marked with the date 1942 and the manufacturer ‘MECo’:imageThe strap is also stamped:imageAccording to the instruction card the signals satchel should hold:

– 2 mics and 2 phones (one for the officer)

– 1 batteries, (spare)

– 1 hooks, brace (spare)

– The instruction card

The actual batteries and junction box should have been stored in a separate pack on the back, but by all accounts only the satchel was used for much of the time so the wireless operator actually had somewhere to carry his own personal kit!

As far as I am aware this satchel was made in both Britain and Canada. I have not seen Australian, Indian or South African examples but that does not mean there was not production in these countries.

Larkspur Radio Aerial Bag

In the aftermath of the Second World War, the British Army introduced a new radio system called (retrospectively) the ‘Larkspur’. Unlike wartime sets Larkspur used VHF frequencies so was more reliable and the cases were hermetically sealed to allow them to be used in a variety of atmospheric conditions. The radios came into widespread use in the late 1950s and early 1960s and remained in use until replaced by ‘Clansman’ in the 1970s, the old Larkspur system remained in use into the 1980s however. I have now started to put together a Larkspur set, and like my WS38 and WS88 sets this will be a back burner project, picking up items as and when I find them at a price low enough for a tight Yorkshireman!

My first piece is the subject of tonight’s post, the aerial bag for the radio:imageThe bag is made from cotton webbing, with leather straps and buckles to secure the main pouch for the aerials, which broke down into six sections. Two pockets are fitted to the front of the bag, secured with press studs. The larger one is at the end of the bag:imageWhilst a smaller one is provided near the top flap:imageThese pockets held two metal reels of cord for use as guy ropes, one aerial earthing attachment and three guy rope ground spikes. On the rear is a belt loop and a pair of leather straps and buckles:imageThe case has large stencilled lettering on the rear, reading ‘CASE AERIAL CAT’ catalogue numbers are also provided, an old style ZA stores code and a newer NSN number:imageThis is a starting point for a new collecting area in post war radios, there seems to be an awful lot of components to these sets compared with the earlier radio sets. They are however far cheaper than wartime sets…

WS38 Throat Microphone

I have slowly been building up the accessories for my WS38 radio set and the latest addition to the collection is the throat microphone. Throat microphones were very common in the Second World War, and combined with a set of headphones allowed the radio operator to keep his hands free:The microphone consists of two pillow shaped carbon microphones that sit on the throat:These are joined by a metal link piece, with the microphone designation printed on it:Wires come out of each microphone receiver:And go to a central Bakelite junction box which converts them into a single pair of wires to go back to the main radio set:The microphone is secured around the neck with an elastic strap, a wire hook and eye allow it to fasten, a leather pad protecting the skin from the catch:A stamped metal buckle is provided for adjustment:This example is still in the original cardboard box it was first issued with:Throat microphones are particularly useful on battlefields as they work well even with loud background noise in a way more traditional microphones would not as they pick up vibrations directly from the voice box and convert that into sound rather than sound coming out of the mouth. Here we see Free French Commandos just before D-Day with a number of WS-38 operators wearing throat microphones like this one:

Artillery Loud Speaker Control Box

I love a nice piece of British communications gear, and tonight we are looking at a really interesting new addition to my collection. The ‘Telephone Loud Speaker Control Unit’ was issued to artillery batteries during the Second World War and allowed the battery commander to communicate with the four guns in the unit and provide immediate instruction on things such as range, shell type required and corrections. Altogether the set comprised the control unit (which we are looking at tonight), batteries and four speaker/transmitter units that went out to each of the guns. The control box was in effect a miniature switchboard for a five way field telephone. As with most British Army communications kit of World War Two, the control unit is housed in a stout wooden box, with the contents painted on the lid:imageThe box weighs 22lbs when complete, so is a heavy piece of kit. There would have been a carrying strap which is now missing (although will not be difficult to replace). Opening the box up we can see it splits into two parts, with the main switchboard in the bottom of the box and storage for headphones and microphone in the lid:imageFour terminals are provided to connect each of the speaker/transmitter units to. A switch beneath allows each or multiple gun sites to be chosen to speak with, a bulb lighting up to show which ones are connected:imageA pair of terminals are provided on the main control panel, the larger being for the microphone (which I am sadly missing):imageThe smaller terminal allows the headphones to be plugged in:imageThe back part of the bottom half of the box has two coiled wires with terminals:imageThese are to attach the system to a battery box, and standard Niphan plugs are attached to the ends of the cables:imageThe lid of the control unit holds the accessories for the set, with a tinplate cover revealing a space for the microphone:imageThe top of the cover has details on how to operate the set, note also that this set was manufactured by Truvox, other examples were produced by Tannoy:imageAs with the microphone, a white outline indicates where the headphones are to be stowed:imageThese are secured in place by a webbing strap with a turn buckle:imageA small tinplate cover reveals a space for spare bulbs for the control box:imageThe headphones provided are very similar to those used on other British Army radio and communications sets, with a pair of Bakelite speaker units and a wire and web harness to attach them over the operator’s head:imageIn this great photograph we can see Lieutenant LW Spurr directing the fire of the 25 pounder guns of the 4th Field Regiment, Royal Canadian Artillery near Antwerp with one of these control units:tannoyA typical order from a Gun Position Officer to the crews of the guns might be, “HE, 117, Charge 3, zero 346 degrees, angle of sight 2 degrees, right ranging 7700, fire”. This meant the guns were to fire an HE Shell, with a 117 direct action fuze, using a charge 3, at an angle of elevation of 346 degrees deviation from the guns zero line, at an angle of elevation of two degrees, only the two  guns furthest to the right of the controller are to fire and the range is 7700 yards.