Military Paraphernalia
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Mine Detector Type 4C
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Contents of the box
Detector head assembly, Electronic unit, Headphones,
Headphone extension lead, Battery extension lead
Two test targets, Log book, Telescopic handle, Measuring
stick
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The log book shows it
was regularly tested from 1989 to its last operational date of
1996 by 28th Engineering Regiment, BFPO31, wherever that is *,
and a label on the box declares it was finally sold in January
1998.
* I looked it up and found BF1
0AJ, Hameln Germany (Pied Piper territory?) |
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The detector takes a 9
volt battery with a clip the same as a PP3, one of which is included,
and the box is very substantial and waterproof when closed with
its 6 clips. The seller wouldn't budge from his asking price
of £10.
Sometime I'll unpack it all
and see if it works.
I was browsing round an antique
shop the other day and noticed a large wooden box with military
markings, that looked strangely familiar.
I opened the lid and inside
was a P6 mine detector (see below). Shock... I used to manage
the Department that designed these things! Seeing it being sold
as an antique wasn't too pleasing. I asked the proprietor about
it. It's got batteries fitted and we tried it out. It works OK
he said and it'll cost you £90. I said we used to charge
MoD nearer £1200 and declined his offer. Somewhere I've
got one. I'll dig it out and add a picture. It's the same type
I demonstrated to the Swedish Army (click
to see). I also saw a P7 advertised on Ebay (see below), but
again a bit expensive for an impulse buy. The P7 was developed
by my Department at Plessey in the Thatcher days when terrorist
activity in Northern Ireland was at its peak. It was designed
for detecting the command wires to explosive devices hidden along
roads. These wires were difficult to detect as they were often
extremely thin to avoid detection, but the P7 used a section
of the command wire to link a transmitter and receiver in the
detector head. Plessey made around 120 or so (at least) and made
loads of money from the PDS contract. The reason being that the
P7 was used as a height detector by soldiers. A "height
detector" you might ask...
Well, have you noticed how heavy
anything military is? A clue to this is the P7 height detector.
When a search for command wires
was about to take place a platoon was sent by helicopter to inspect
suspect fields. Once ready to disembark a soldier would chuck
out his P7. Usually it broke. If it did he'd wait a little longer
before jumping out. Over the years we progressively strengthened
the P7 by using stronger and stronger (and of course heavier)
materials until I guess the P7 survived the drop but the odd
soldier presumably broke his leg ? I wonder if anyone reading
this knows anything about the P7 and just how successful, or
otherwise was it? It can't have been too bad because one day
an Irish policeman rang me wanting to buy a few.
One day someone had the bright
idea to make a commercial version of P7 and flog it to the local
water company to find buried pipes. An engineer turned up at
the local water board offices and went out with our new P7 to
demonstrate it. Much to his surprise the water board chap fished
out of his car a divining rod. At the end of the day we'd proved
P7 worked well, but no better than the divining rod so we abandoned
the idea.... |
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Reading the accompanying
text, the detector has two 70cm coils suspended from a bamboo
pole. A remote box, carried by a chap wearing headphones, contains
a battery, a condenser, a buzzer and a balancing circuit. In
operation, the two coils are coupled by a metal object (in this
case a large unexploded shell) inducing noise from the buzzer
radiated by one coil, into the second, where it is heard in the
headphones. The circuit is described as induction balance which
is the same method used by the Plessey P7 used for command wire
detection. |
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Pictures of the Plessey
P7 designed for use in Northern Ireland
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And here's a Plessey
P6 (L4A1)
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