GPO Vehicles

P.O. ENGINEERING DEPT.
ENGINEERING INSTRUCTIONS
TOOLS & TRANSPORT
VEHICLES
B 1203
Issue 1, 17.8.64

The 10-cwt. Area Radio Investigation Vehicle, Type 1 (Morris)

1. General
This Instruction describes the l0-cwt. Area Radio Investigation Vehicle, Type 1 (Morris) and the facilities which it provides.  The vehicle is designed for use on Area radio investigation duties where the Minor Van, modified for radio investigation work, is inadequate.

2. Description
A general view of the vehicle is shown above. It is a forward-control type with a body shell of welded pressed-sheet-metal construction, having windows along each side.  Overall dimensions are: length 12 ft. 9 in., width 5 ft. 8 in. and height 6ft. 9in.

3. Security screen
The cab and body portions are separated by a metal-mesh screen to enable the body to be locked (see par. 9) without restricting access to the cab. This screen incorporates a folding type of access door to give personnel access between cab and body.  Provision of hinged traps in the bottom of the screen permits the carriage of a ladder (par. 10).  Additionally, the top sections of the screen are removable to give access to the sliding-door pockets (par. 18) for vehicle maintenance purposes.

4. Seating arrangements
In the cab section there is a single passenger seat in addition to that for the driver.  Both these seats are adjustable.  A further two passengers can be accommodated on a bench seat on the near-side of the body section although this seat is provided for the use of a man operating equipment within the body.  The bench seat can be folded back and secured against the side of the vehicle, to give access to under seat lockers (par. 8) and to improve access to equipment carried within the body.

5. Writing facilities
A small writing flap is mounted above the engine cover directly in front of the forward passenger seat.  The flap has a sliding support which should always be pulled out when the flap is extended, to avoid straining the hinges.  To gain access to the engine the complete table unit can be raised and secured by a strap type of fastener.  If necessary the complete unit may be removed by loosening two wing nuts which secure it just below the near-side windscreen.

6. Lockers
An apparatus locker (see right) with three compartments is mounted along the off-side of the body section above the ladder space (par. 10).  Access to this locker is obtained via three sliding panels in the top.  The two rearmost compartments are lined with shock-absorbent material for the protection of test equipment and can be combined into a single large compartment by withdrawing the removable intervening vertical partition.  The remaining compartment is fitted out with two removable trays (displayed on the right) each of which is sub-divided by removable partitions to give adjustable storage for small suppressor components.  Space is available below the trays for a tool bag, tool wallets or larger suppressor items.

7. A feature of the sliding panels (one upper and two lower) forming the top of the main locker is that they can be utilized to mount and set out equipment for making tests from within the vehicle, provision being made to secure such equipment in transit by using expanding rubber luggage straps.  To make the whole arrangement as flexible as possible, the upper sliding panel may be fixed in one of three alternative positions and each lower panel in one of two positions, using flat slide bolts recessed into the upper faces of the panels.  Additionally, the two lower panels can be completely removed via a gap in the sliding channel, to facilitate the removal of the vertical partition separating the two rearmost compartments.

8. There is an under seat locker on the near-side of the body.  Access to this locker is obtained by lifting up the near-side bench seat which forms the locker lid.  A further small locker under the forward passenger seat accommodates all the vehicle tools except the two long sections of the lifting jack handle which are secured in spring clips on the off-side sliding door pocket.

9. Locking arrangements
The near-side cab door and the rear doors are equipped with standard FA 600 or FP 750 series locks to enable the contents to be safeguarded when the vehicle is left unattended for short periods (the off-side cab door is fitted with an inside turn-button).  For extended absences additional security can be obtained by padlocking the rear doors and the access door between cab and body.  A hasp and staple are fitted to the rear doors and the interior door bolt is suitably modified for this purpose.  Additionally, the bolts securing traps or removable panels in the security screen are located on the body side.  Under seat lockers are equipped with hasp and staple so that they can be padlocked.

Padlocks l.25 in.... are the correct padlocks for use on this class of vehicle. It is advisable to keep all padlocks on the vehicle to one suite.

[NOTE:- Padlocks 1.25 in.... are sometimes of the spring self-locking type.  To prevent the accidental locking of keys inside the van body, it is recommended that the padlock keys should not all be carried together.]

10. Ladder carrying facilities
A Ladder, Extension, No. 4A or No. 5 can be carried on the floor in the space below the off-side apparatus locker.  The head of the ladder projects through a trap in the bottom of the security screen, into a recess formed below the driver's seat.

11. Aerials
A rotatable aerial-mast housing with coaxial connector box is located towards the rear of the body (Fig. 2).  This device is controlled remotely by a handle positioned to the rear of the driver's seat and can be rotated through 400 degrees, care being necessary to ensure that the coaxial cable connecting the connector box and test equipment is long enough to permit this travel.  Elongated mounting slots for the remote control handle allow for the adjustment of the remote control wires.

12. Each aerial array (made up locally as required) to be used with the rotatable mast housing requires to be mounted on a 1 in. outside diameter tubular support mast, having two 0.25 in. slots cut diametrically opposite in the bottom end.  When the mast is slid into the top of the mast housing, it is turned until these slots locate on to corresponding studs inside the housing above the connector box.  The studs have projections outside the housing to form a pointer so that, if the aerial array is lined up with the slots in its support mast, the orientation of the aerial can be followed by an operator inside the vehicle.  Connexions to the aerial array are made via a coaxial lead threaded through the support mast and having a short tail with coaxial plug to terminate on a coaxial socket inside the connector box.

13. A business radio aerial (Aerial-units Nos. 17/1 and 17/2) may be fitted centrally on the roof if required.  The Workshop Supervisor/Mechanic-in-Charge will fit the aerial base on receipt of a formal request from the Assistant. Engineer concerned.

WARNING:- The driver must be extremely careful of low overhead clearances when an aerial array is in position above the roof

14. Power supply for test apparatus
A 5 amp point, mounted above the off-side body window, is wired to the vehicle battery via low resistance leads and is intended for use with test apparatus.  Additional power capacity can be obtained by the use of separate 6V car type batteries which should be stowed in a convenient position, using the rubber battery trays supplied with the vehicle. Fig. 2 shows the extra batteries stowed below the operator's seat.

15. Use of apparatus within the vehicle
While the uses of radio test equipment to be used inside the vehicle are described in the various instructions appertaining to Radio Investigation duties, there are a number of specific precautions to be observed in relation to its use on vehicles.
These precautions are:-

(a) Do not drive while wearing earphones

(b) Do not drive holding a microphone or handset

(c) Ensure that legal requirements for the operation of a television set in a vehicle are scrupulously observed. These are:-

1. No part of the television screen shall be directly or indirectly visible to the driver while he is in the driving seat.

2. None of the television set controls, other than the main switch and sound volume control, shall be within the driver's reach while he is in the driving seat.

3. A television set must not be used in circumstances and in a position such that it might cause distraction to the driver of any other vehicle on the road.

16. Maximum load
The maximum load to be carried by this vehicle is 10 cwt. excluding the driver.  In cases of doubt a simple check can be made by weighing the vehicle in its moving condition, i.e. complete with contents, personnel, full petrol tank, etc.  This gross moving weight must not exceed 40 cwt.  Any weighbridge charges involved should be passed to Freight and Cartage.

17. Sliding doors
Under normal driving conditions the cab sliding doors should be kept shut while the vehicle is in motion, as a precaution against accidents. In foggy weather or when manoeuvring in a congested space it may nevertheless be found an advantage to have the doors open. In such circumstances the doors should be secured in the open position by the turn catches near the bottom of each door.

18. Sliding door pockets
The glazed door pocket panels hinge upwards when the securing screws along the bottom edges are freed, to give access for cleaning purposes.

19. First aid kits
The driver's first-aid kit is located above the windscreen.  If the personnel regularly using the vehicle are equipped with a larger first-aid kit, this should he mounted in a prominent and accessible position using two leather straps.  Two suitable leather straps complete with buckles should be purchased locally where necessary.

20. Windows, lighting and heating
Natural light is provided by the windows in the body and rear doors, the two rear-side windows having sliding panels for ventilation.  For night work an internal light is mounted in the body above the near-side windows with the control switch above the off-side door pocket.  This general lighting can be augmented by a bench lamp if desired.

21. Blinds
Blinds are provided on the body windows and rear doors.  These facilitate the use of a television set within the body and combat difficulties of dazzle from other road users using headlights at night.

22. A cab heater/windscreen demister of the re-circulation type is fitted.

23. Vehicle battery
The vehicle battery is housed beneath the vehicle floor and access is obtained via a floor trap situated immediately behind the driver's seat.  A budget lock secures the floor trap.

24. Spare wheel
This is housed at the rear below the floor and, to remove it, the hinged rear number plate should be slid towards the near-side to release a spring-loaded catch, and then raised out of the way.

25. Damage to paintwork
The outside of the van has a synthetic enamel finish.  Attempts to re-touch any scratched or damaged parts should not be made by the staff using the vehicle.  Work of this nature will be undertaken by the Workshop Supervisor/ Mechanic-in-Charge when necessary and during periodic overhauls.

26. Signwriting
Standard inscriptions for signwriting are given in C 0015.

27. Speed limit
See D 0022

An extract from
THE POST OFFICE ELECTRICAL ENGINEERS' JOURNAL
Volume 53, Part 1, April 1960

A Vehicle for Radio Investigation Work

A description is given of a new vehicle for use on radio investigation duties. The vehicle is based on an existing standard type, the Area Planning and General Purpose Vehicle.


INTRODUCTION
The first type of vehicle specially developed for radio investigation (R.I.) work and capable of transporting two men with their equipment was introduced in 1935. It was an adaptation of a postal van and was known as the 8 cwt R.I. Vehicle. It had a non-metallic body - a feature then thought essential - and could mount an external aerial. This type of van remained the standard vehicle for radio interference work until 1947 when the Morris R.I. Car (Fig. 1) came into service. This vehicle, like its predecessor, had a non-metallic body and was based on a Morris 8 cwt chassis. One hundred and sixty-five of these R.I. Cars were provided and they proved to be a marked improvement on the previous type. In addition, modified Minor Vans were introduced to meet the greatly increased need for vehicles for the radio investigation service.

Experience with these vehicles under a wide range of conditions, however, naturally revealed scope for further improvements. In particular, the roof sockets for aerials were difficult to keep weather-tight, and the need for less-cramped operating conditions and better stowage arrangements for the apparatus became apparent. The security of the apparatus itself also presented problems. Since a non-metallic body was no longer considered essential, it was possible to base the design of a new vehicle on an existing standard type - the Area Planning and General Purpose Vehicle - which seemed likely to provide the facilities required.

THE NEW VEHICLE
The general appearance of the new vehicle is shown above. The large side-windows and glazed pockets for the sliding side-doors help to give a good all-round view from the operator’s position, so enabling him to pass instructions to the driver when they are “homing” on a source of interference.

Interior Fittings
In addition to the usual seats for the driver and passenger, a bench seat is provided on the near side as an operating position. The space beneath this seat provides convenient stowage for batteries, for which rubber trays are provided, and a cabinet on the offside provides a table on which apparatus may be mounted. The table is lit by a lamp fitted over the near-side door pocket. A 5-amp socket-outlet over the table is connected to the vehicle battery.

A folding table is fitted in front of the passenger seat to provide additional writing space.

A combined heater and demister is provided, and blinds are fitted to the side windows for use as required when operating within the vehicle.

Stowage and Security of Apparatus
To provide security for the apparatus carried in the vehicle an expanded-metal screen is used to divide the cab from the rest of the interior of the body. Since it is necessary to provide access from the cab to the rest of the interior, the screen is arranged in the form of two fixed panels, one on each side, and a folding door hinged to the near-side panel. When open, this door folds flat against the fixed near-side panel. The side panels themselves are formed from two smaller panels, the upper parts being detachable to give access to the glazed door-pockets for cleaning purposes. Hinged flaps are provided at the bottom of the off-side fixed portion and at the bottom of the folding door to permit a ladder to be carried.

Both the screen and the rear doors can be padlocked, while the opening side-windows are, of course, secured on the inside by window catches.

The full security provided enables the stowage facilities for the radio apparatus to be combined with the bench space required to mount the apparatus when it is in use. No separate locked accommodation is therefore required. The apparatus storage takes the form of a cabinet divided into compartments. Access to the compartments is obtained via sliding panels which form the top of the cabinet and provide the bench space. Apparatus mounted on the panels may be secured in position with elastic luggage-cords anchored to flush-fitting anchor pins inserted in the panels. By leaving one panel free it is possible to gain access to any of the


compartments by sliding the panels as required without it being necessary to disturb any apparatus set up for use on the bench space. Flush-mounted bolts enable the panels to be locked in position to prevent any uncontrolled movement when the vehicle is in motion.

Aerial Mounting
To avoid the difficulties experienced with aerial sockets on previous vehicles, the aerial support on the new vehicle transmits no stress from the aerial to the vehicle roof and at the same time provides a weathertight mounting. The mounting consists of a tubular support extending from a batten on the vehicle floor to the roof and terminating at each end in a socket. This tubular support provides a direct channel for water entering at the roof end to a hole in the floor beneath the lower socket. The sockets are so arranged that the support can be rotated either directly by hand or by remote control from the cab. The remote-control gear, which enables the aerial to be rotated through 400° if required, is operated by a handle fitted behind the driver’s seat; this handle is connected to the tubular support by flexible steel wires encased in steel conduit. The conduit and the control gear are fixed to a detachable batten to facilitate vehicle maintenance.

A junction box with a hinged flap carrying a coaxial connector is fitted to the tubular support to enable the coaxial lead from the aerial to be connected to the apparatus. The hinged flap of the junction box is fitted with a gasket to provide a watertight joint when the flap is closed.

To mount an aerial it is only necessary to insert the stub end into the open end of the tubular support on the vehicle roof. The stubs of the various types of aerial are slotted to engage with a pin fitted to the tubular support just below the underside of the roof. This pin projects outside the tubular support and provides an indication of the direction to which the aerial has been rotated.

The aerial support is fitted at the rear of the vehicle to enable the operator to mount the aerials while standing on the vehicle floor.

Last revised: August 08, 2023