Docstoc

FV432 Clansman Wiring Harness an

Document Sample
FV432 Clansman Wiring Harness an Powered By Docstoc
					FV432 Clansman Wiring Harness and
Associated Control Boxes / Equipment /
Headsets


Introduction
Harness For A Two Radio Setup
Harness For A Three Radio Setup
The Pressel Unit For Audio Headsets, Microphones, etc
The Commander’s Special Audio Equipment
The “Crew Box 2 Set” (or CB2)
The “Drivers Box”
The “Amplifier AF Loudspeaker” (or AAFL)
Helmets and Headgear
Two-wire Audio Handsets


Introduction

The original wiring loom fitted to all FV432s, for the provision of intercom and
radio communications, was the old Larkspur type. This was current in the
early sixties, which was the period when all of the mark I and II FV432
vehicles were produced. The 1950s Larkspur technology was valve based, so
when Clansman was introduced, the vast majority of in-service 432s (all that I
have ever seen) were converted to this newer and more reliable transistor and
chip based standard.

Fortunately for the private restorer, the MOD always leaves the wiring harness
installed in decommissioned vehicles, but unfortunately nearly always
removes all of the control boxes, radios, and ancillaries. The saving grace is
that all of the missing goodies are available through numerous suppliers.

All of the intercom and radio control-box equipment connects directly into the
Clansman Harness. This is a twelve-core cable that runs around the vehicle in
a loop, thus allowing one plug disconnection or cable failure to occur without
loss of any service. Figure 1 shows a cable connector and a control-box
mounted connector – all occurrences of these within the vehicle adhere to
these standard genders.
Figure 1- Clansman Harness cable connector and a control-box
mounted connector

The cable carries power to the control boxes, audio for intercom, audio for up
to three radio sets, and I believe signalling information – I presently do not yet
have any info on the latter. It does not provide power to the radios or to the
loudspeaker amplifier.

The Clansman loom is standard on ALL British military vehicles, pending the
introduction of the new Bowman system, but this article serves to cover only
the FV432 installation.

There are two basic harness configurations – one for 432s having up to two
radios, and one for up to three radios. The differences will be shown first,
followed by the many commonalities.

The central control box for the harness is either the IB2 or IB3. It is mounted
on the commander’s side of the crew compartment dividing bulkhead, next to
the commander’s right shoulder.

Examine the Clansman harness cabling at this location in the 432. If you have
three dangling 7-way audio-type connectors, one dangling 2-way power
connector, and two dangling 12-way connectors then you have a three radio
Clansman harness. The mounting holes are closer together on the IB3 than
on the IB2 since the IB3 is a smaller box – thus you have to have installed the
correct box at this location.
Harness For A Two Radio Setup

The two-radio flavour harness is based around the “Interconnecting Box 2
Radio” (or IB2).The IB2 is shown in Figure 2 and is mounted on the
commander’s side of the crew compartment dividing bulkhead, next to the
commander’s right shoulder.




Figure 2 - “Interconnecting Box 2 Radio” or IB2

It provides control, connectivity and 18 volt DC power for the Clansman
harness. It enables the two installed radios, or one installed and one remote,
to be connected for manual or auto rebroadcast. It also allows a remote user
to be connected into (and to control) the harness to use an installed radio or
to communicate with the crew over the intercom. Finally, it provides a single
pressel / headset outlet.

In order to distribute the regulated 18 volts, it has its own 2 pin socket for
connection to the vehicle’s 24/28 volt power system, as provided by the rear
generator on the power pack – the one that is shaft driven from the transfer
box.Items that can be connected to the remote terminals (over a 5 km two
wire cable run) include the “Remote Personal Unit” RPU, the “Handset
Remote Control” HSR, another vehicles IB2/IB3, and the two-wire battery
powered field telephones. The RPU is similar to the CPU shown in Figure 7
but connects with two core cable.
Harness For A Three Radio Setup

The three-radio flavour harness is based around the “Interconnecting Box 3
Radio” (or IB3), as shown in Figure 3, with the option of the “Crew Box 3 Set”
(or CB3) being necessary if you are wealthy enough to have three radios
connected.

The IB3 is mounted on the commander’s side of the crew compartment
dividing bulkhead, next to the commander’s right shoulder.




Figure 3 - “Interconnecting Box 3 Radio” (or IB3) installed in FV432.

The IB3 shown here has the yellow face-plate, indicating the newer noise-
reduction generation.Also shown top left is the tightly fitting Commander’s Box
Fixed, and at the bottom, one of the VRC353 radios.

It provides connectivity and 18 volt DC power for the Clansman harness. It
enables the three installed radios to be connected, but only to be operated in
pairs. It does allow a remote user to be connected into the harness to use (but
not control) an installed radio or to communicate with the crew over the
intercom. It does not provide radio rebroadcast facilities.

In order to distribute the regulated 18 volts, it has its own 2 pin socket for
connection to the vehicle’s 24/28 volt power system, as provided by the rear
generator on the power pack – the one that is shaft driven from the transfer
box.
Items that can be connected to the remote terminals include the IB2 / IB3 in
other vehicle, and the two-wire battery powered field telephones. Non-
powered devices cannot be connected (e.g. the RPU,HSR).
The unit has 2 pairs of 12 pin Harness sockets. Connecting the standard pair
to the Harness allows the crew and commander to use radio sets A and B.
Connecting the “ACTIC” pair instead allows radios A and C. However, all
three radios can be utilised by CB3 attached crew (see below) by connecting
the standard Harness leads to the IB3’s standard Harness sockets, and the
CB3 ACTIC connected leads (2 off) to the IB3’s ACTIC sockets.

The “Crew Box 3 Set” (or CB3) is shown in Figure 4 and is mounted slightly
right-of-centre on the crew side of the power pack compartment's bulkhead,
approximately 1 foot below roof height. It is a larger box than the standard
CB2 unit, so can only be employed if your vehicle has the correctly spaced
hull fixing bolts.

It attaches to the Harness in the standard way, but also has two additional
ACTIC Harness connections that must be connected to the two ACTIC
sockets on the IB3 if you need the CB3 to operate three radios. The CB3 unit
allows up to two headsets (with Pressel) to use the intercom system or any of
the three radios. Another of the three radios may also be monitored in the
right earphone.




Figure 4 - “Crew Box 3 Set” (or CB3)
The Pressel Unit For Audio Headsets, Microphones, etc

The Pressel unit fits between the 7 pin “audio” socket on any Clansman audio
equipment (including radios, CB2, CB3, etc) and the 7 pin headset / helmet /
handset. See Figure 5. It allows the headset user (etc) to :

a)    listen to the radio and intercom traffic that is available on the Harness,

b)    to transmit his voice on the selected radio,

c)   to speak over the intercom.

When the headset user wishes to speak, he presses the rubberised side-bar
on the pressel, then releases when done. There are headset users who have
difficulty with this since both of their hands are busy – for example the driver.
For this case, there is a two position “Microphone Live – ON/Off Switch”,
lockable with a screw, that selects between a permanently live mike and side-
bar switch operation.




Figure 5 - “Pressel Unit”

They are available in the original black and the newer green. This is not just a
cosmetic issue – the green units supply an output voltage which is a
requirement of the new generation ANR “Acoustic Noise Reduction”
headsets. It is safe to operate any combination of headset (etc) with either
pressel type, but the ANR headset / black pressel combination provides
headphone facilities only (no mike).

Note that some headsets / helmets / handsets have a pressel built-in, to
either the cable or handset.
The Commander’s Special Audio Equipment

Instead of using a CB2-type box to connect to the Harness, the commander
uses the “Commander’s Box Fixed” or (CBF) (see figure 6) mounted on the
underside of the roof to the right of his shoulder (when seated). The unit has a
pair of 12 pin sockets for Harness connection, as normal. This unit is difficult
to operate as it faces downwards, and like the other boxes, has recessed
controls. A large 10-way curly cable connects the unit to the “Commander’s
Personal Unit” (or CPU) (see figure 7) which fits around the neck, and into
which the commander’s 7 pin headgear is connected. Between them, the two
units provide the commander with CB2-type facilities, with the important and
frequently used controls being on the CPU.

The CPU only allows selection of radios A and B, so is not ideal for the 3
Radio installation. It is however fine for private owners not needing to operate
three radios simultaneously! Whilst using one radio, it allows the commander
to monitor the other It also allows the commander to use the intercom
system.

One oddity of the CBF/CPU combination is that it does not supply an output
voltage to the Headset, this being a requirement of the new generation ANR
“Acoustic Noise Reduction” headsets. This is a shame since the 432 is a loud
girl by any measure, and the driver / commander need all the noise reduction
that they can get.




Figure 6 - the “Commander’s Box Fixed” or (CBF)

I have found the commander’s long curly cable very very useful since my 432
has to be reversed-parked into a tight spot, and the commander can stand on
the roof at the back of the vehicle to give the driver instructions over the
intercom.
Figure 7 - the “Commander’s Personal Unit” or (CPU)

A rather worn example, but shown with the curly cable and neck strap.
The “Crew Box 2 Set” (or CB2)

The “Crew Box 2 Set” (or CB2), as shown in Figure 8, is the main unit by
which the troops can plumb-into the audio system. It allows up to two
headsets (with Pressel) to use the intercom system. It also allows the operator
to select and operate either radio A or B and to monitor the other. The unit
has a pair of 12 pin sockets for Harness connection, as normal. There are
several locations for these boxes, and most FV432s have three of them, with
an option of one for the driver – the driver can use a different type of unit, see
the next section for details.




Figure 8 - the “Crew Box 2 Set” (or CB2)

The CB2 shown here has the yellow face-plate, indicating the newer noise-
reduction generation.

These units are sighted (a) centrally above the rear troop door, (b) just above
the NBC fan control switch, (c) slightly right-of-centre on the crew side of the
power pack compartment's bulkhead just below roof height

Some folks attempt to fit them either-side of the rear troop door, since the
mounting studs and cabling happen fit the CB2 unit. However, these locations
are reserved for two ARFAT units that have nothing to do with the Clansman
Cabling Harness – more of this radio related info later.
The “Drivers Box”

Although many installations of the Clansman Harness within FV432s use a
CB2 box for the driver, to be strictly correct the Driver’s Box should be used.
The substitution is possible because the hull mounting studs and the
Clansman Harness connections are identical. The unit has a pair of 12 pin
sockets for Harness connection, as normal.

The unit is shown in Figure 9 and provides the driver with intercom
communications ONLY – i.e., no radio access! I can only think that drivers are
not classed as being responsible enough to TX/RX over the air-waves.
Perhaps someone can enlighten me here.

One puzzle is why it serves two crew since it provides a pair of 7 pin audio
connections instead of one. This may be for use in a tank where there is
loader crew-member, also needing a headset but no radio access




Figure 9 - the “Drivers Box”
The “Amplifier AF Loudspeaker” (or AAFL)

The audio amplifier sits on a right-angled bracket on the bulkhead of the
offside fuel tank just above the track sill, as shown in Figure 10. It has a pair
of 12 pin sockets for Harness connection, as normal, plus a 2 pin socket for
connection to the vehicle’s 24/28 volt power system.




Figure 10 - The “Amplifier AF Loudspeaker” (or AAFL) unit in its FV432
location

For sources of audio input, the operator can select between Intercom, Radios
A & B, or the external source – the latter is connected to the amp via a
standard 7 pin audio socket (matches the headsets) or a pair of connector
posts. The connector posts can accept input from a wide variety of sources,
including the “Remote Personal Unit” RPU, the “Handset Remote Control”
HSR, and the two-wire battery powered field telephones, or a civilian radio
receiver if you fancy some Radio 2.

Output to up to four speakers, wired in any combination of serial or parallel
(yes, honest) is via a pair of connector posts or a standard 7 pin audio socket.
The latter is used to connect the amp to the two speakers, mounted either
side of the rear troop door just below the roof height – see Figure 11.
Figure 11 – The offside “Loudspeaker Vehicle Mounting” unit in its
FV432 location, just above the troop compartment door. The amplifier is
just out-of-shot bottom left. Also shown centrally above the door is a
CB2.
Helmets and Headgear

All of the following can be connected to any of the Clansman Harness Boxes
that have an “audio” socket, like IB3, CB2, CB3. This section shows a
selection (not exhaustive) of what is available.




Figure 12

This item is usually used by the troop’s radio man since he can disconnect
from the vehicle and plug straight into his personal radio – any of the
clansman types, including PRC349, 350,351,320. It is particularly suitable for
this since it leaves one ear free. Very comfy to wear inside the standard
infantry helmet. A socket is provided for the optional NBC mask mike.
Standard Clansman 7 pin connector.




Figure 13

This is known as the “bone dome” crewman’s helmet as it usually exposes a
large area of your forehead. It is difficult to put on as it feels as if your ears are
ripping off! Very reliable unit with built-in (non-removable) audio gear but not
particularly comfortable. The headset has a manual LF noise reduction
control. Shown hear with optional NBC mask microphone. Standard
Clansman 7 pin connector.
Figure 14

This is the standard crewman’s helmet, and has presstud connected audio
gear (see Figure 15). The unit is very comfortable to wear and to get on and
off. The headset has a manual LF noise reduction control and a socket for the
optional NBC mask mikeStandard Clansman 7 pin connector.




Figure 14a

This is the side-view of the helmet shown in Figure 14. It clearly shows the
mike and one of the earphones.
Figure 15

This is the standard crewman’s headset that can be worn with helmet (as
shown in Fig 14/14a) or without. The unit is very comfortable to wear and to
get on and off. The headset has a manual LF noise reduction control and a
socket for the optional NBC mask mike.. Standard Clansman 7 pin connector.




Figure 16

This skull cap uses the same audio gear as shown in Figure 15. The mike &
earphones are sewn into the very comfortable cap and a socket is provided
for the optional NBC mask mike. Standard Clansman 7 pin connector.
Figure 17

This is the standard headset of the new “ANR” noise reduction type, without
helmet. The unit is very comfortable to wear and to get on and off. The auto
LF noise reduction feature is very impressive and useful in the FV432, but
does mean that a green pressel is needed and cant be used with the
commander’s the CBF/CPU kit. This headset can be worn under the standard
infantry helmet and has a socket for the optional NBC mask mike. Standard
Clansman 7 pin connector.




Figure 18

This is the standard Clansman 7 pin handset and can be used in a telephone
style in the FV432, but is usually connected directly to any of the radios, both
personal and vehicle mounted. It has an integral pressel switch.
Figure 19

The left-hand unit is a combined mike & speaker with built-in pressel / tunic
clip. It can be used in any standard 7 pin Clansman audio socket. Usually
connected directly to any of the radios, both personal (very good for this) and
vehicle mounted. An earphone with a 3.5mm jack can be used in place of the
speaker. Good examples cost around £15. The right-hand “Combined” unit is
functionally identical and is worn around the head on a strap. It differs in that it
is for occasional mike use only as you have to move it from your ear to your
mouth – tricky with the strap.




Figure 20

The left-hand unit is a telephone-style handset with built-in pressel and can be
used in any standard 7 pin Clansman audio socket. Usually connected directly
to any of the radios, both personal and vehicle mounted. The right-hand unit
shows one of the green pressels that supports the newer “NRZ” noise-
reduction headsets.
Figure 21

This item is usually used by the troop’s radio man since he can disconnect
from the vehicle and plug straight into his personal radio – any of the
clansman types, including PRC349, 350,351,320. It is particularly suitable for
this since it leaves one ear free. It has a pressel unit built into the cable (with a
tunic clip) and a throat mike. Very comfy to wear inside the standard infantry
helmet. It has a standard Clansman 7 pin connector.
Two-wire Audio Handsets




Figure 22

This is the two wire handset “HSR” usually connected remotely over twin
cable to the “Remote” terminals on either a Clansman Radio (like VRC353) or
on the IB2. It has a built-in pressel and a tone generator “call” button.




Figure 23

This is the standard field telephone that connects over twin cable to the
“Remote” terminals on either a Clansman Radio (like VRC353) or on the
IB2/IB3, or to another phone. It has a built-in pressel and a tone generator
“call” button and takes 4 ‘D’ cells.
Pictures Shown in this article are courtesy of Army Radio Sales
Company and Dave Norfolk.

Most of the items shown above are available from Army Radio Sales
Company.

Click on the links below to connect to their website.



http://www.armyradio.com/

http://www.armyradio.co.uk/

sales@armyradio.com



The information has been taken from an article on www.FV432.com which,
as its name suggests, is an excellent resource for those who have an interest
or are lucky enough to own one of these fine vehicles.

My interest in Clansman kit stems from my original need for an intercom in my
1954 Daimler Ferret armoured car. If you want to know more about these
vehicles and the guys who operated them check out my site :
www.FV701.com



Robert Soar
billy_ruffian@fireflyuk.net


December 2003

				
DOCUMENT INFO
Shared By:
Categories:
Stats:
views:220
posted:5/6/2010
language:English
pages:20