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'[PIC]: Need some help with a PIC monotoring system'
2001\04\17@152431 by Richard

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Hi everyone.

I need to build a system for me to monitor my guards. What I need this
system to do is:
   ~ every hour (or 1/2 hr) notify the guard that he has to patrol
   ~ the guard has to 'check-in' at various check points (there are four of
them, I was thinking about using long range remotes with a receiver in the
guard room. The guard has to check-in, in a sequence, so that he cannot
stand in one place and 'press the button' four times.)
   ~ Once the guard has completed his patrol, he has to 'reset' the system
by pressing a button inside the guard room.
   ~ If the patrol was a success (there where no problems and the guard
checked-in in the specified time limit) then the system must notify the
control room which is located at different premises, either by radio via a
repeater or through telephone lines using a tele-dialler, that the patrol
was successful and that all is ok.
   ~ If something happened on the patrol (if the time limit expired or the
guard pressed his panic remote) then the system must notify the control room
that there is a problem and that someone must be sent out to the site.

Firstly, what is the best way to get the signal to the control room. If the
system sends and audio signal (through the use of a voice chip) with a
pre-recorded message or some form of data. If it is data, then something
must be at the receiving end to decode it, maybe a PC running a program
which answers a modem upon detection of a ring and then decodes the data,
this will require some programming skills which I mostly lack. But can it be
done?

Also what PIC would be most suited to this? Could it be possible to use a
16f84?

I would appreciate any help that you guys can give.

Thanks,
Richard

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2001\04\17@153958 by Thomas N

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Wow!!! You have the money to pay the guards?!  I don't think you have any
problem paying someone to build the system for you!

Thomas


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2001\04\17@155601 by Drew Vassallo

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{Quote hidden}

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2001\04\17@155804 by Andrew Warren

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Richard <.....PICLISTKILLspamspam.....MITVMA.MIT.EDU> wrote:

> I need to build a system for me to monitor my guards.

Richard:

What you've described is a "watchman's clock", various versions of
which have been in use for centuries.

It'll be much cheaper to buy a system than to build it; if you search
the web for "watchman's clock" or "guard tour", I'm certain that
you'll find a vendor who has exactly what you need.

-Andy


=== Andrew Warren --- EraseMEaiwspam_OUTspamTakeThisOuTcypress.com
=== IPD Systems Engineering, CYSD
=== Cypress Semiconductor Corporation
===
=== Opinions expressed above do not
=== necessarily represent those of
=== Cypress Semiconductor Corporation

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2001\04\17@155812 by Drew Vassallo

picon face
Sorry for the repost... accidentally hit "send" instead of cancel.

>I need to build a system for me to monitor my guards. What I need this
>system to do is:

This sounds like a major undertaking.  EE's would spend months (if not more)
developing something like this.  Why not just see what's available on the
market for timecard-style monitoring?

There are a number of access-control manufacturers who may have similar
products that may suit your needs.

--Andrew
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2001\04\17@161514 by Richard

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lol. Actually its a security company. The guards are at one of our clients
premises. There is a system available commercially which does something
similar to this, but it doesn't offer the sending of the notifications in
'real-time. What it does is logs the time the guards get to the check
points, which can be download the next day and printed. But this is not what
I want. I need it tell the people in the control the instant there is
something wrong(i.e. the guard presses his panic button or something
similar).

Also, that system has a price tag of over R 6 000.00 (To give you an idea,
the average salary of a guard here in South Africa is approx. R 1 500 to R 2
000 a month, so you can see that it is quiet expensive).

I would prefer to build one myself at say, tops R 2 500.00 Also over here a
PIC16f84 goes for around R 80.00 a piece. That's why I would like to know if
that chip will do.

Richard.

{Original Message removed}

2001\04\17@161732 by Richard

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Ok, thanks. I'll do some searching on the net and see what I can get.

Richard

----- Original Message -----
From: "Andrew Warren" <aiwspamspam_OUTCYPRESS.COM>
To: <@spam@PICLISTKILLspamspamMITVMA.MIT.EDU>
Sent: Tuesday, April 17, 2001 9:50 PM
Subject: Re: [PIC]: Need some help with a PIC monotoring system


{Quote hidden}

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2001\04\17@164553 by Richard

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I must admit, it sounds like a huge project. But the real trouble is getting
the system to communicate with the control room.

I built a quick one for the mean time (took almost a day to build and
install) it consists of a few timers and four long range remotes and a voice
module.
The timers are connected to the module and to a relay which PTT's a two-way
radio working through a repeater. The thing is that it is a 'community
repeater' (from a 2-way radio company) and the audio level is set a bit high
so that the repeater rejects sounds (which is normally noise) with levels
below the setting. And with the output from the voice module being a bit low
it most of the message gets rejected and it comes out sounding like a
scratched CD.

Now the only way I can think of is to set the levels lower, which would
upset the other users on the repeater.

If I use the radio on a simplex channel (I.E. not through a repeater), then
it works fine, but the distance it has to transmit is to far for simplex.

If I can get this communicating thing to work, then I'm sure it becomes a
simple task getting the check points and everything to work fine utilising a
micro such as a PIC?

Richard
{Original Message removed}

2001\04\17@165222 by Douglas Wood

picon face
You might try using a Dallas Semi iButton for the ID tag. That should
simplfy the ID part of the project.

Douglas Wood
Software Engineer
spamBeGonedbwoodspamBeGonespamkc.rr.com

Home of the EPICIS Development System for the PIC and SX
http://epicis.piclist.com

{Original Message removed}

2001\04\17@170502 by Bob Blick

face
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If you can do without the "panic" feature, you could just have fixed
stations and a traveling unit. Plug the traveling unit into the fixed
units and there you go.

Of course Dallas semi makes iButtons that they'd be happy to sell to
you. Even though they are horridly expensive, you wouldn't have to do it
yourself.

Really it sounds like you have way too much spare time on your hands - I'm
jealous.

-Bob

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2001\04\17@170645 by Richard

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I've heard of the iButton. Ok I'll look into it.

Thanks Douglas,

Richard
----- Original Message -----
From: "Douglas Wood" <TakeThisOuTdbwoodEraseMEspamspam_OUTKC.RR.COM>
To: <RemoveMEPICLISTspamTakeThisOuTMITVMA.MIT.EDU>
Sent: Tuesday, April 17, 2001 10:57 PM
Subject: Re: [PIC]: Need some help with a PIC monotoring system


{Quote hidden}

levels
{Quote hidden}

simplex.
> >
> > If I can get this communicating thing to work, then I'm sure it becomes
a
> > simple task getting the check points and everything to work fine
utilising
{Quote hidden}

this
> > > >system to do is:
> > >
> > > This sounds like a major undertaking.  EE's would spend months (if not
> > more)
> > > developing something like this.  Why not just see what's available on
> the
> > > market for timecard-style monitoring?
> > >
> > > There are a number of access-control manufacturers who may have
similar
{Quote hidden}

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2001\04\17@172331 by Richard

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Lol, thanks Bob.
It helps when you're your own boss.

Richard.

PS. I've just done a search on the net and found a system that could work
for me. I've emailed them for a price and some more details, so I'll see
what I can do with that system.

http://www.powies.net/gps/RFID.htm


{Original Message removed}

2001\04\18@052121 by Alan B. Pearce

face picon face
>    ~ the guard has to 'check-in' at various check points (there are four
of
>them, I was thinking about using long range remotes with a receiver in the
>guard room. The guard has to check-in, in a sequence, so that he cannot
>stand in one place and 'press the button' four times.)
>    ~ Once the guard has completed his patrol, he has to 'reset' the system
>by pressing a button inside the guard room.


How about each check in station and the ID unit the guard carries each have
a serial number device such as a Dallas i-button in it along with an RTC. To
check in the guard holds his ID device against the check in point device at
which point they exchange serial numbers and log the time of exchange. This
would be done through an RFID type technique.

When the guard gets back to the guard room he holds his ID device against
the guard room check in point, and serial numbers are exchanged again. This
does the 'reset' of the system. Once this is done, the guard room point then
downloads the log from the guards ID device, thereby providing an auditable
log of times and check ins. There is also some sort of connection from the
check in points to signify that a check in was made, but not carrying the
serial number info, although it would need to signal that it was a valid
serial number. These contact times are checked against the downloaded log to
see that they were done in correct order.

Perhaps too complicated for what you are trying to do?

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2001\04\18@075807 by Olin Lathrop

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> How about each check in station and the ID unit the guard carries each
have
> a serial number device such as a Dallas i-button in it along with an RTC.
To
> check in the guard holds his ID device against the check in point device
at
> which point they exchange serial numbers and log the time of exchange.
This
> would be done through an RFID type technique.

Hmm.  So a group of thieves would only need to surprise the guard on his
rounds, tie him up somewhere, then have one guy walk around as usual with
the ID tag.  Meanwhile the rest of the gang has all weekend to clean the
place out.


********************************************************************
Olin Lathrop, embedded systems consultant in Littleton Massachusetts
(978) 742-9014, EraseMEolinspamspamspamBeGoneembedinc.com, http://www.embedinc.com

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2001\04\18@081907 by Alan B. Pearce
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>Hmm.  So a group of thieves would only need to surprise the guard on his
>rounds, tie him up somewhere, then have one guy walk around as usual with
>the ID tag.  Meanwhile the rest of the gang has all weekend to clean the
>place out.

Which is why he needs to use it to log in at the guard house at the end of
the round. If he does not then an alarm should be raised to the security
company premises as originally mentioned. If the gang can get into the guard
house to do this then there is a problem in the way the system is
implemented which is beyond any logging system. If the ID unit is used as a
key system to gain access then that is also a security flaw unless used with
some sort of PIN system.

It may be that using a PIN number at each logging point would help with any
security problem, but this is still not a total solution.

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2001\04\18@085000 by Drew Vassallo

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>Hmm.  So a group of thieves would only need to surprise the guard on his
>rounds, tie him up somewhere, then have one guy walk around as usual with
>the ID tag.  Meanwhile the rest of the gang has all weekend to clean the
>place out.

Heh, good thought.  Why not implement a biometric ID system?  Well... then I
suppose you could cut off his finger or eyeball to use it for the ID... but
you'd have to have quite the stomach for that one!

Any system can be defeated, it's just a matter of to what lengths/risks
you're willing to go to do it.

--Andrew
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2001\04\18@111216 by Craig Cassin

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I do not know about the signal to the control room,
but i suggest that you use a battery powered pic
for the guard. he carries it around and plugs it into the various stations,
which will have different pins shorted inside the connector. The portable
pic can keep track of the guard's route. This will save you
transmitters or wiring.

-Craig

{Original Message removed}

2001\04\18@115926 by Alan B. Pearce

face picon face
>I do not know about the signal to the control room,
>but i suggest that you use a battery powered pic
>for the guard. he carries it around and plugs it into the various stations,
>which will have different pins shorted inside the connector. The portable
>pic can keep track of the guard's route. This will save you
>transmitters or wiring.

The problem with doing this is there is no feedback from the check point to
the guard house, so you get no "timeout" until the guard gets back to the
guard house. If the guard gets tapped on the head before the first check
point, then the burglars have the whole round time plus the "timeout" period
to do their business. If there is contact from each check point back to the
guard house, then this time can be considerably shortened, and corrective
action taken if need be.

The other problem with this arrangement is that it requires physical
contacts between the check point station and the guard's unit. If this can
be done using an RFID system then no physical contact is needed. If no
contact is required with the guard house then a system like that used by
store security systems to stop stock going out the door could be used, where
the check point station has a tuned circuit like gets attached to items in a
shop, and the guard's unit detects this.

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2001\04\18@120135 by Roman Black

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Alan B. Pearce wrote:
>
> >Hmm.  So a group of thieves would only need to surprise the guard on his
> >rounds, tie him up somewhere, then have one guy walk around as usual with
> >the ID tag.  Meanwhile the rest of the gang has all weekend to clean the
> >place out.
>
> Which is why he needs to use it to log in at the guard house at the end of
> the round. If he does not then an alarm should be raised to the security
> company premises as originally mentioned. If the gang can get into the guard
> house to do this then there is a problem in the way the system is
> implemented which is beyond any logging system. If the ID unit is used as a
> key system to gain access then that is also a security flaw unless used with
> some sort of PIN system.
>
> It may be that using a PIN number at each logging point would help with any
> security problem, but this is still not a total solution.


Maybe a bar code attached to the Guard, ie ink stamp on
the forearm, could be checked at each station. Maybe in
conjunction with a new pin number for that day??

Keep in mind that any "key" devices can be removed from
the guard, even "knowlege" systems can be compromised if
they interrogate the guard. All you can do is make it
more complex to hack the system.

I watched the mafia movie "Goodfellows" the other night,
they paid off the guards and got tips and passwords that
way. Extremely easy. So how much do your guards take home
each week?? Any of them got mortgages?? Are they willing
to "look the other way" for $5,000 in cash, etc??
:o)
-Roman

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2001\04\18@123445 by Kev

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> Maybe a bar code attached to the Guard, ie ink stamp on
> the forearm, could be checked at each station. Maybe in
> conjunction with a new pin number for that day??
>

Great, now the guard looses his arm in a heist after the crooks determine
the new PIN #.

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2001\04\18@134407 by Richard

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This could be a problem, any ideas to get around this?

Richard

----- Original Message -----
From: "Olin Lathrop" <RemoveMEolin_piclistKILLspamspamEMBEDINC.COM>
To: <PICLISTSTOPspamspamspam_OUTMITVMA.MIT.EDU>
Sent: Wednesday, April 18, 2001 1:49 PM
Subject: Re: [PIC]: Need some help with a PIC monotoring system


> > How about each check in station and the ID unit the guard carries each
> have
> > a serial number device such as a Dallas i-button in it along with an
RTC.
{Quote hidden}

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2001\04\18@135218 by Richard

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hmm, that's a good idea. Something to think about.

Richard

----- Original Message -----
From: "Craig Cassin" <KILLspamcraigcasspamBeGonespamJPS.NET>
To: <EraseMEPICLISTspamEraseMEMITVMA.MIT.EDU>
Sent: Wednesday, April 18, 2001 5:11 PM
Subject: Re: [PIC]: Need some help with a PIC monotoring system


> I do not know about the signal to the control room,
> but i suggest that you use a battery powered pic
> for the guard. he carries it around and plugs it into the various
stations,
{Quote hidden}

four
> of
> > them, I was thinking about using long range remotes with a receiver in
the
> > guard room. The guard has to check-in, in a sequence, so that he cannot
> > stand in one place and 'press the button' four times.)
> >     ~ Once the guard has completed his patrol, he has to 'reset' the
> system
> > by pressing a button inside the guard room.
> >     ~ If the patrol was a success (there where no problems and the guard
> > checked-in in the specified time limit) then the system must notify the
> > control room which is located at different premises, either by radio via
a
> > repeater or through telephone lines using a tele-dialler, that the
patrol
{Quote hidden}

data,
> > this will require some programming skills which I mostly lack. But can
it
{Quote hidden}

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2001\04\18@135835 by Richard

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True, pay-offs can be very problematic. And the fact remains that if someone
really wants something, he is going to get it, one way or the other.

The only thing we can do is make it more difficult for them to get their
objective and hopefully deter them.

Richard

{Original Message removed}

2001\04\18@140415 by David VanHorn

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At 07:42 PM 4/18/01 +0200, Richard wrote:
>This could be a problem, any ideas to get around this?

Sounds like the old DTex watchclock scheme, but with "smart keys".

One possible bit of security you could add, is that they have to be punched
in some particular order.
Guards deal with this all the time. You have stations that you have to
check hourly, some twice a shift, and some once a shift.  Most guards will
fall into a pattern anyway. You can dictate that pattern and you can detect
variances from that pattern.
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2001\04\18@141047 by David VanHorn

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>
> > I watched the mafia movie "Goodfellows" the other night,
> > they paid off the guards and got tips and passwords that
> > way. Extremely easy. So how much do your guards take home
> > each week?? Any of them got mortgages?? Are they willing
> > to "look the other way" for $5,000 in cash, etc??
> > :o)
> > -Roman


More common than you might think.
However, a smart operator will have a weak link, closely monitored.

I used to do a similar approach on alarm systems.
Bell box on wall, with wire running up outside wall..
Don't cut that wire!  Bell box is empty, but the wire is an input to the
system.

Same on keyswitches. I'd use a cheap keyswitch and LED plate outside. The
LEDs are active, but the keyswitch being turned just trips the system. The
real control is a digital pad inside, where you have to trip a sensor to
get to it.

If you give them a not-too-obvious "easy-in", they'll usually use it. :)


The control box should be put in a non-obvious location, since a fire axe
will disable most systems pretty effectively.

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2001\04\18@142619 by Chris Pringle

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picon face
All very well having all this stuff, but provided you don't make the system
public knowledge, it really shouldn't be that bigger issue. If people are
that determined, they will find a way to get around the system. A PIN should
be fine, just don't make the system public knowledge. If the criminal
doesn't even know the system exists, then they won't try to circumvent it.

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{Original Message removed}

2001\04\18@143230 by Bill Westfield

face picon face
> ~ the guard has to 'check-in' at various check points (there are four of
>them, I was thinking about using long range remotes with a receiver in the
>guard room. The guard has to check-in, in a sequence, so that he cannot
>stand in one place and 'press the button' four times.)

Can you use a cell phone?  Each check-in location would be a "thing" that
matches the accessory connection on the phone.  When you plug the phone
into it, it'd dial a pre-programmed number and send appropriate
encrypted/timestamped data string using appropriate data technology (or
even touchtones, I guess.)  The "emergency" function is probably already
provided by the phone (dial a programmed number when you hold the 9 key for
five seconds on my nokia, I think.)  Depending on ecconomics, you can let
the guards keep the phone as a perk...

(all this solves is the communications issue.  Most of the watchman's
clock things I've seen that look like they might have instantaneous
communications look like they're designed to have wiring in the wall -
quite an expensive proposition for a (perhaps temporary) customer.)

BillW

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2001\04\18@152435 by Bill Westfield

face picon face
> >Hmm.  So a group of thieves would only need to surprise the guard on his
> >rounds, tie him up somewhere, then have one guy walk around as usual with
> >the ID tag.  Meanwhile the rest of the gang has all weekend to clean the
> >place out.

And this differs from having one guy drag the guard around at gunpoint and
forcing him to perform the appropriate security measures?  These are GUARDS,
right - not the sort of person one expects extraordinary heroics from?

BillW

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2001\04\18@153653 by David VanHorn

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>
>And this differs from having one guy drag the guard around at gunpoint and
>forcing him to perform the appropriate security measures?  These are GUARDS,
>right - not the sort of person one expects extraordinary heroics from?

If you do it right, he just takes them to one station out of order, or one
station that he usually dosen't go to, (how would they know?) and that sets
off the alarm, with a code that they have a guard under duress.

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2001\04\18@174333 by Bob Ammerman

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Both the ID tag and a PIN are required to check in.

There are 2 PINs:

- The normal PIN.
If used everything is 'hunky dory' and the system runs as normal.

- A panic PIN.
If used the guard is under duress and a 'silent alarm' goes out to the
control center.

Now if a bad guy gets the guard he can't use the ID tag without the PIN, and
the guard can give him the panic PIN instead of the real one.

Bob Ammerman
RAm Systems
(contract development of high performance, high function, low-level
software)


{Original Message removed}

2001\04\19@042248 by Roman Black

flavicon
face
Richard wrote:
>
> This could be a problem, any ideas to get around this?

> > > How about each check in station and the ID unit the guard carries each
> > have
> > > a serial number device such as a Dallas i-button in it along with an
> RTC.

> > Hmm.  So a group of thieves would only need to surprise the guard on his
> > rounds, tie him up somewhere, then have one guy walk around as usual with
> > the ID tag.  Meanwhile the rest of the gang has all weekend to clean the
> > place out.


OK, what about a hidden system, like a RF ID unit hidden in
the guard's clothes. Then make him visibly press a key code
also. Thieves watching would see the key code and may even
get that by interrogating a guard.

But when they try to use it, the RF ID tag is not present
and the alarm goes off. Many good alarms feature an obvious
system combined with a hidden system, for this reason.
:o)
-Roman

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2001\04\20@024711 by Peter L. Peres

picon face
$0.02: Whatever you do, build some sort of diversity into the guard tour
(don't have two successive guard tours be the same, or a predictable
pattern). The kind with the fixed guard tour enforced by clocks and
checkpoints, you can stop using and save the money for better insurance
coverage. You guess why.

Peter

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