Vibration sensor
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Posts: 46,084
I once saw a cool demonstration where a rubber band when plucked in
the path of a laser beam, a tone is produed on a speaker. What I
want to do is so that I can take that tone into a stamp, measure the
fequence and determin the rate of vibration and possibly amplitude.
My main interest now is how to do the vibration to tone conversion.
Would it work by simply puttin a photo-resistor in front the laser
beam, the amplitude of the signal received will oscilate. I can
take this into an amp and produce the sound on a speaker. would it
work?
Al
the path of a laser beam, a tone is produed on a speaker. What I
want to do is so that I can take that tone into a stamp, measure the
fequence and determin the rate of vibration and possibly amplitude.
My main interest now is how to do the vibration to tone conversion.
Would it work by simply puttin a photo-resistor in front the laser
beam, the amplitude of the signal received will oscilate. I can
take this into an amp and produce the sound on a speaker. would it
work?
Al
Comments
mentioned on the list before. My guess is if you want to do this, you're
going to have a challenge with the stamp, since you're going to have to
query the detector and output wave changes at several thousand cycles per
second. The better way might be to leave the stamp out and tie a
photoresistor directly to an oscillator. what will happen is as the
photoresistor resistance goes up, you will have the upside of the sine
(or possibly square) wave, and as the photoresistance goes down it will be
the downside of that wave. I would also have some concerns that the
photoresistor might not react as quickly as you'd want it to, but you
could also use phototransistors, which I don't really know much about.
On Fri, 28 Dec 2001, brownstamp wrote:
> I once saw a cool demonstration where a rubber band when plucked in
> the path of a laser beam, a tone is produed on a speaker. What I
> want to do is so that I can take that tone into a stamp, measure the
> fequence and determin the rate of vibration and possibly amplitude.
>
> My main interest now is how to do the vibration to tone conversion.
> Would it work by simply puttin a photo-resistor in front the laser
> beam, the amplitude of the signal received will oscilate. I can
> take this into an amp and produce the sound on a speaker. would it
> work?
>
>
> Al
>
>
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>
Sean T. Lamont, CTO / Chief NetNerd, Abstract Software, Inc. (ServNet)
Seattle - Bellingham - Vancouver - Portland - Everett - Tacoma - Bremerton
email: lamont@a... WWW: http://www.serv.net
"...There's no moral, it's just a lot of stuff that happens". - H. Simpson
photoresistor. Perhaps a phototransistor that is pre-biased to sharpen its
response. With that, you may also need to condition the output to square it
up. Once you have a clean square wave, you can use PULSIN to measure the
period and determine the frequency of the vibration signal.
-- Jon Williams
-- Parallax
In a message dated 12/28/01 2:21:13 PM Central Standard Time,
brownstamp@y... writes:
> I once saw a cool demonstration where a rubber band when plucked in
> the path of a laser beam, a tone is produed on a speaker. What I
> want to do is so that I can take that tone into a stamp, measure the
> fequence and determin the rate of vibration and possibly amplitude.
>
> My main interest now is how to do the vibration to tone conversion.
> Would it work by simply puttin a photo-resistor in front the laser
> beam, the amplitude of the signal received will oscilate. I can
> take this into an amp and produce the sound on a speaker. would it
> work?
>
[noparse][[/noparse]Non-text portions of this message have been removed]
after amplifying & rectifying the signal and feeding it to a cap with a
resistance across it.
From: <jonwms@a>
> You'd probably want to use a component that responds faster than a
> photoresistor. Perhaps a phototransistor that is pre-biased to sharpen
its
> response. With that, you may also need to condition the output to square
it
> up. Once you have a clean square wave, you can use PULSIN to measure the
> period and determine the frequency of the vibration signal.
>
> -- Jon Williams
> -- Parallax
>
>
> In a message dated 12/28/01 2:21:13 PM Central Standard Time,
> brownstamp@y... writes:
>
>
> > I once saw a cool demonstration where a rubber band when plucked in
> > the path of a laser beam, a tone is produed on a speaker. What I
> > want to do is so that I can take that tone into a stamp, measure the
> > fequence and determin the rate of vibration and possibly amplitude.
> >
> > My main interest now is how to do the vibration to tone conversion.
> > Would it work by simply puttin a photo-resistor in front the laser
> > beam, the amplitude of the signal received will oscilate. I can
> > take this into an amp and produce the sound on a speaker. would it
> > work?
> the path of a laser beam, a tone is produed on a speaker. What I
> want to do is so that I can take that tone into a stamp, measure the
> fequence and determin the rate of vibration and possibly amplitude.
>
> My main interest now is how to do the vibration to tone conversion.
> Would it work by simply puttin a photo-resistor in front the laser
> beam, the amplitude of the signal received will oscilate. I can
> take this into an amp and produce the sound on a speaker. would it
> work?
I seem to recall reading about using an accelerometer for measuring
vibration. If I'm not mistaken, Analog Devices has an appnote on doing just
that with their ADXL series of accelerometers. There have been plenty of
discussions on this list about connecting the ADXL parts to the Stamp as
well so you should be able to find some code to get you started as well.
Mark Hillier, VE6HVW
President, HVW Technologies Inc.
Canadian Distributors of Parallax Products and other Neat Stuff
Tel: (403)-730-8603 Fax: (403)-730-8903
See our NEW FPGA Experimenter Board
http://www.hvwtech.com/intro-fpga.htm
publications: 1) Techical Note: Using the ADXL202/ADXL210 with the
Parallax Basic Stamp Module to speed algorithm development; 2)AN-411:
Acceleration to Frequency Circuits, which describes V/F conversion.
Note that the ADXL202e is in a very small chip scale package.
Dennis
WSR
Pasadena CA
Original Message
From: Mark Hillier [noparse]/noparse]mailto:[url=http://forums.parallaxinc.com/group/basicstamps/post?postID=q22xO9m9_9Zhzf8d0mLwjOALUlJ_oIonGtOp70-McoItCmSTJrGWHLxiaAixFIQAtIIDg6duJgFV]Mark@H...[/url
Sent: Friday, December 28, 2001 3:34 PM
To: basicstamps@yahoogroups.com
Subject: Re: [noparse][[/noparse]basicstamps] Vibration sensor
> I once saw a cool demonstration where a rubber band when plucked in
> the path of a laser beam, a tone is produed on a speaker. What I
> want to do is so that I can take that tone into a stamp, measure the
> fequence and determin the rate of vibration and possibly amplitude.
>
> My main interest now is how to do the vibration to tone conversion.
> Would it work by simply puttin a photo-resistor in front the laser
> beam, the amplitude of the signal received will oscilate. I can
> take this into an amp and produce the sound on a speaker. would it
> work?
I seem to recall reading about using an accelerometer for measuring
vibration. If I'm not mistaken, Analog Devices has an appnote on doing
just
that with their ADXL series of accelerometers. There have been plenty of
discussions on this list about connecting the ADXL parts to the Stamp as
well so you should be able to find some code to get you started as well.
Mark Hillier, VE6HVW
President, HVW Technologies Inc.
Canadian Distributors of Parallax Products and other Neat Stuff
Tel: (403)-730-8603 Fax: (403)-730-8903
See our NEW FPGA Experimenter Board
http://www.hvwtech.com/intro-fpga.htm
To UNSUBSCRIBE, just send mail to:
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I am a new member, I am working on a school project and need a
sensor to detect the vibration of vocal cords, for example when we
are screaming or a bark of a dog. Does anyone have a suggestion or
experience working with a good reliable, cheap sensor???
Thanks
Nima
More details about what you mean by "detect the vibration" would be
helpful. Since sound is usually produced, a low-cost microphone would
be the obvious answer.
Dennis
Original Message
From: nima_jahedi [noparse]/noparse]mailto:[url=http://forums.parallaxinc.com/group/basicstamps/post?postID=q9Nob28yTZJfMQkjKLKrhQ6UpGiq4zG5HxBoLdbMRR-g1oX8KesSMqQ23mM18dDKNj6fBDoBS4SKjE8]nima_jahedi@y...[/url
Sent: Monday, March 22, 2004 12:16 PM
To: basicstamps@yahoogroups.com
Subject: [noparse][[/noparse]basicstamps] Vibration Sensor
Hi Everyone
I am a new member, I am working on a school project and need a
sensor to detect the vibration of vocal cords, for example when we
are screaming or a bark of a dog. Does anyone have a suggestion or
experience working with a good reliable, cheap sensor???
Thanks
Nima
we used to do monthly vibration readings on all the equipment (keep noise
down so subs can't spot us from toooo far away).
As a civvy, I'm still into the mechanics and have quite a bit of light to
medium machinery that I look after. A full blown vibration analysis kit
won't make it past the bean counters but... I wonder if I could rig up
something using my BOE/BS2. Not a full spectrum analysis or anything, just
something where i could record the characteristics of a machine and compare
to previous readings.
Haven't any background in building anything like this but, I'm thinking
perhaps some form of accellerometer? Perhaps two or three to grab each axis?
Any thoughts?
I'm playing with accelerometers. Not sure if they're sensitive enough for
you (well, if you can measure a small enough value!). But they require a
static orientation!
Original Message
From: "nima_jahedi" <nima_jahedi@y...>
To: <basicstamps@yahoogroups.com>
Sent: Monday, March 22, 2004 3:16 PM
Subject: [noparse][[/noparse]basicstamps] Vibration Sensor
> Hi Everyone
>
> I am a new member, I am working on a school project and need a
> sensor to detect the vibration of vocal cords, for example when we
> are screaming or a bark of a dog. Does anyone have a suggestion or
> experience working with a good reliable, cheap sensor???
>
> Thanks
> Nima
>
>
>
>
> To UNSUBSCRIBE, just send mail to:
> basicstamps-unsubscribe@yahoogroups.com
> from the same email address that you subscribed. Text in the Subject and
Body of the message will be ignored.
>
> Yahoo! Groups Links
>
>
>
>
>
http://www.msiusa.com/piezo/
As you jiggle the film back and forth a varying voltage is generated.
You can use an ADC to measure it or a comparator setup with a trip point
to let you know when you've exceeded something.
It's pretty cool.
What I did was attach a small weight to the end of the strip to increase
it's sensitivity to small movements. With the right weight it can detect
small air movements in the room.
Original Message
From: PatM [noparse]/noparse]mailto:[url=http://forums.parallaxinc.com/group/basicstamps/post?postID=i9rW0xmJ_zzP9xLNPxRvu8UI3TCZjFOcU72UT8j5ukBY9D8P6EjW9fiIVA-lsOfoRdqu--nC8xE]pmeloy@s...[/url
Sent: Monday, March 22, 2004 7:18 PM
To: basicstamps@yahoogroups.com
Subject: RE: [noparse][[/noparse]basicstamps] Vibration Sensor
Actually - this got me thinking... When I was a Marine Engineer in the
Navy,
we used to do monthly vibration readings on all the equipment (keep
noise
down so subs can't spot us from toooo far away).
As a civvy, I'm still into the mechanics and have quite a bit of light
to
medium machinery that I look after. A full blown vibration analysis kit
won't make it past the bean counters but... I wonder if I could rig up
something using my BOE/BS2. Not a full spectrum analysis or anything,
just
something where i could record the characteristics of a machine and
compare
to previous readings.
Haven't any background in building anything like this but, I'm thinking
perhaps some form of accellerometer? Perhaps two or three to grab each
axis?
Any thoughts?
To UNSUBSCRIBE, just send mail to:
basicstamps-unsubscribe@yahoogroups.com
from the same email address that you subscribed. Text in the Subject
and Body of the message will be ignored.
Yahoo! Groups Links
vibrations because of 1) where they're located, and 2) altering their
vibrational mode characteristics. The instruments I'm familiar with use
stroboscopic video, all coupled with a thin, flexible fiberoptic scope
-- expensive little devices.
Dennis
Original Message
From: PatM [noparse]/noparse]mailto:[url=http://forums.parallaxinc.com/group/basicstamps/post?postID=dSyETiv-tthw-nrvOJl5GdXMh4cXxL0hAA0WLM3fY3-SVANPXGzP9TRdpdweqWVd5hY9TWE]pmeloy@s...[/url
Sent: Monday, March 22, 2004 5:18 PM
To: basicstamps@yahoogroups.com
Subject: RE: [noparse][[/noparse]basicstamps] Vibration Sensor
Actually - this got me thinking... When I was a Marine Engineer in the
Navy, we used to do monthly vibration readings on all the equipment
(keep noise down so subs can't spot us from toooo far away).
As a civvy, I'm still into the mechanics and have quite a bit of light
to medium machinery that I look after. A full blown vibration analysis
kit won't make it past the bean counters but... I wonder if I could rig
up something using my BOE/BS2. Not a full spectrum analysis or anything,
just something where i could record the characteristics of a machine and
compare to previous readings.
Haven't any background in building anything like this but, I'm thinking
perhaps some form of accellerometer? Perhaps two or three to grab each
axis?
Any thoughts?
I'm not sure if they use it to detect the heat 'flash' as the blood is fired
through yer skin....
But if you set up a litle device to reflect light off of your throat...ya
ok...whatever! !lol too much to worry about!
They have those throat mics....sure you have to push them against the voice
box to get the volume....this action also distorts the box and you get that
odd computer voice.
Piezo is good. Or put a little doppler radar 2inches from the output source
(mouth) and use th edoppler shift from the bad breath. Just be sure to get
a disclaimer signed in regards to eye damage and such!!
Original Message
From: "Earl Bollinger" <earlwbollinger@c...>
To: <basicstamps@yahoogroups.com>
Sent: Monday, March 22, 2004 9:12 PM
Subject: RE: [noparse][[/noparse]basicstamps] Vibration Sensor
> What works pretty good is piezo film sensors. Such as those from
> http://www.msiusa.com/piezo/
> As you jiggle the film back and forth a varying voltage is generated.
> You can use an ADC to measure it or a comparator setup with a trip point
> to let you know when you've exceeded something.
> It's pretty cool.
> What I did was attach a small weight to the end of the strip to increase
> it's sensitivity to small movements. With the right weight it can detect
> small air movements in the room.
>
>
>
Original Message
> From: PatM [noparse]/noparse]mailto:[url=http://forums.parallaxinc.com/group/basicstamps/post?postID=Hj-LYnxb1Uzq8kOE-co5HZkCYfkXG08FW1rJWa24rM1xAJXO8iauL9o5D04_jap5fujyVWg]pmeloy@s...[/url
> Sent: Monday, March 22, 2004 7:18 PM
> To: basicstamps@yahoogroups.com
> Subject: RE: [noparse][[/noparse]basicstamps] Vibration Sensor
>
> Actually - this got me thinking... When I was a Marine Engineer in the
> Navy,
> we used to do monthly vibration readings on all the equipment (keep
> noise
> down so subs can't spot us from toooo far away).
>
> As a civvy, I'm still into the mechanics and have quite a bit of light
> to
> medium machinery that I look after. A full blown vibration analysis kit
> won't make it past the bean counters but... I wonder if I could rig up
> something using my BOE/BS2. Not a full spectrum analysis or anything,
> just
> something where i could record the characteristics of a machine and
> compare
> to previous readings.
>
> Haven't any background in building anything like this but, I'm thinking
> perhaps some form of accellerometer? Perhaps two or three to grab each
> axis?
>
> Any thoughts?
>
>
>
>
> To UNSUBSCRIBE, just send mail to:
> basicstamps-unsubscribe@yahoogroups.com
> from the same email address that you subscribed. Text in the Subject
> and Body of the message will be ignored.
>
> Yahoo! Groups Links
>
>
>
>
>
>
>
>
>
> To UNSUBSCRIBE, just send mail to:
> basicstamps-unsubscribe@yahoogroups.com
> from the same email address that you subscribed. Text in the Subject and
Body of the message will be ignored.
>
> Yahoo! Groups Links
>
>
>
>
>
Original Message
From: "SB" <steve.brady@r...>
To: <basicstamps@yahoogroups.com>
Sent: Monday, March 22, 2004 8:17 PM
Subject: Re: [noparse][[/noparse]basicstamps] Vibration Sensor
> A Piezo? or does that require a mechanical connection??
> I'm playing with accelerometers. Not sure if they're sensitive enough for
> you (well, if you can measure a small enough value!). But they require a
> static orientation!
>
>
>
Original Message
> From: "nima_jahedi" <nima_jahedi@y...>
> To: <basicstamps@yahoogroups.com>
> Sent: Monday, March 22, 2004 3:16 PM
> Subject: [noparse][[/noparse]basicstamps] Vibration Sensor
>
>
> > Hi Everyone
> >
> > I am a new member, I am working on a school project and need a
> > sensor to detect the vibration of vocal cords, for example when we
> > are screaming or a bark of a dog. Does anyone have a suggestion or
> > experience working with a good reliable, cheap sensor???
> >
> > Thanks
> > Nima
> >
> >
> >
> >
> > To UNSUBSCRIBE, just send mail to:
> > basicstamps-unsubscribe@yahoogroups.com
> > from the same email address that you subscribed. Text in the Subject
and
> Body of the message will be ignored.
> >
> > Yahoo! Groups Links
> >
> >
> >
> >
> >
>
>
>
> To UNSUBSCRIBE, just send mail to:
> basicstamps-unsubscribe@yahoogroups.com
> from the same email address that you subscribed. Text in the Subject and
Body of the message will be ignored.
>
> Yahoo! Groups Links
>
>
>
>
>
>
>Don't they use IR to detect heart beats??
>
>I'm not sure if they use it to detect the heat 'flash' as the blood is fired
>through yer skin....
Most likely the IR emitter and detector measure blood density variations as
your heart beats. I don't think this would be good for measuring vocals.
>But if you set up a litle device to reflect light off of your throat...ya
>ok...whatever! !lol too much to worry about!
(snip)
-Beau Schwabe
Original Message
> From: Earl Bollinger [noparse]/noparse]mailto:[url=http://forums.parallaxinc.com/group/basicstamps/post?postID=IeglukV9K-lv85z04IPww4XmHUyuYNUxgMxU0KC6paI2ygK2dup48rSzm855aVAV4gAQyzEo-qAQp4cdcnZwOZE1T6b5]earlwbollinger@c...[/url
> Sent: March 22, 2004 6:13 PM
> To: basicstamps@yahoogroups.com
> Subject: RE: [noparse][[/noparse]basicstamps] Vibration Sensor
>
>
> What works pretty good is piezo film sensors. Such as those from
> http://www.msiusa.com/piezo/
I received my sensors from Digikey (#MSP1006-ND) yesterday. I got the tabs,
not the mass (mass at end of tab increases output voltage - more
sensitivity).
Took my o-scope and a sensor to work and tried them out on some large
machine bearings (5HP and 50HP electric motors and fans). Readings appeared
to be right in the ballpark of what these should be doing!
I've talked to two mechanical engineers in the last couple of days that have
had a lot of vibration analysis experience (one does it as his main
vocation). Both were floored when I said the sensors cost less than $2 and
told them the results I got. MSI's site is getting some heavy perusing I
think!
Just sorting out how to condition the signal so I don't fry any opamps or
ADCs over on the Electronics_101 list now.
Thanks for the pointer to these little babies!
Are we talking about the stuff made with the same plastic that's used
on the gauge for wire wrapping wire? The last I had heard it was made
by a division of AMP, now Tyco. They might have spun off the division
when Tyco glommed AMP.
On another theme, Pat, can you point me to your notes on the XPORT? I
want to see if I can get my Stamp 1 to talk to the one I have.
Gregg C Levine hansolofalcon@w...
"The Force will be with you...Always." Obi-Wan Kenobi
"Use the Force, Luke."· Obi-Wan Kenobi
>
Original Message
> From: PatM [noparse]/noparse]mailto:[url=http://forums.parallaxinc.com/group/basicstamps/post?postID=9DzGBODLXriGOxNfd_UY-MO81nryZpZiLY0Lhr1GwPDJvn8faO-sSZ5lPB3lXhnmevx3b2Az8A]pmeloy@s...[/url
> Sent: Thursday, April 01, 2004 11:07 PM
> To: basicstamps@yahoogroups.com
> Subject: RE: [noparse][[/noparse]basicstamps] Vibration Sensor
>
> >
Original Message
> > From: Earl Bollinger [noparse]/noparse]mailto:[url=http://forums.parallaxinc.com/group/basicstamps/post?postID=Z3yZr4fqROjLJGvDGRd25MK6SybOAIldmJXbhCH3nCesi73pP9ljyf6jyW8JBc1hjYtt_6sLLOgNEZfTy4fSlA]earlwbollinger@c...[/url
> > Sent: March 22, 2004 6:13 PM
> > To: basicstamps@yahoogroups.com
> > Subject: RE: [noparse][[/noparse]basicstamps] Vibration Sensor
> >
> >
> > What works pretty good is piezo film sensors. Such as those from
> > http://www.msiusa.com/piezo/
>
> I received my sensors from Digikey (#MSP1006-ND) yesterday. I got
the tabs,
> not the mass (mass at end of tab increases output voltage - more
> sensitivity).
>
> Took my o-scope and a sensor to work and tried them out on some
large
> machine bearings (5HP and 50HP electric motors and fans). Readings
appeared
> to be right in the ballpark of what these should be doing!
>
> I've talked to two mechanical engineers in the last couple of days
that have
> had a lot of vibration analysis experience (one does it as his main
> vocation). Both were floored when I said the sensors cost less than
$2 and
> told them the results I got. MSI's site is getting some heavy
perusing I
> think!
>
> Just sorting out how to condition the signal so I don't fry any
opamps or
> ADCs over on the Electronics_101 list now.
>
> Thanks for the pointer to these little babies!
Those sensors are really neat.
I love the simplicity of it all.
Original Message
From: PatM [noparse]/noparse]mailto:[url=http://forums.parallaxinc.com/group/basicstamps/post?postID=S5jdgdEV9Le8-ePUV0cHaT_-qi2njEVFkgQydatbaD2U0bcMsZW8fq22upi-MZLSQ0qkeVjHiQ]pmeloy@s...[/url
Sent: Thursday, April 01, 2004 10:07 PM
To: basicstamps@yahoogroups.com
Subject: RE: [noparse][[/noparse]basicstamps] Vibration Sensor
>
Original Message
> From: Earl Bollinger [noparse]/noparse]mailto:[url=http://forums.parallaxinc.com/group/basicstamps/post?postID=EKZHQmCMBbCX1HCY3AzKjCWpIcLCrpdLvLL-Y89Kwu3TTgv02E4qjBFHalAUgyeODsolmwh6BIQsPqgDNTJUrL2E7Q]earlwbollinger@c...[/url
> Sent: March 22, 2004 6:13 PM
> To: basicstamps@yahoogroups.com
> Subject: RE: [noparse][[/noparse]basicstamps] Vibration Sensor
>
>
> What works pretty good is piezo film sensors. Such as those from
> http://www.msiusa.com/piezo/
I received my sensors from Digikey (#MSP1006-ND) yesterday. I got the
tabs,
not the mass (mass at end of tab increases output voltage - more
sensitivity).
Took my o-scope and a sensor to work and tried them out on some large
machine bearings (5HP and 50HP electric motors and fans). Readings
appeared
to be right in the ballpark of what these should be doing!
I've talked to two mechanical engineers in the last couple of days that
have
had a lot of vibration analysis experience (one does it as his main
vocation). Both were floored when I said the sensors cost less than $2
and
told them the results I got. MSI's site is getting some heavy perusing I
think!
Just sorting out how to condition the signal so I don't fry any opamps
or
ADCs over on the Electronics_101 list now.
Thanks for the pointer to these little babies!
To UNSUBSCRIBE, just send mail to:
basicstamps-unsubscribe@yahoogroups.com
from the same email address that you subscribed. Text in the Subject
and Body of the message will be ignored.
Yahoo! Groups Links
>Are we talking about the stuff made with the same plastic that's used
>on the gauge for wire wrapping wire? The last I had heard it was made
>by a division of AMP, now Tyco. They might have spun off the division
>when Tyco glommed AMP.
>
It is PVDF (polyvinylidene fluoride). Those sensors are bimorphs,
with PVDF bonded to a different plastic, (mylar?), so that when the
structure vibrates, it stretches and compresses the PVDF layer.
Non-piezo forms of PVDF are in fact used to make pipes and chemical
fittings and woven cloth filters and wire insulation. When the
material is rolled out at a certain elevated temperature under a high
electric field, the polymer molecules line up and the material
becomes polarized, more so than just about any other organic polymer
known. Like a crystal or piezo ceramic, it can generate a voltage
on its opposite faces when deformed, or it can deform when a voltage
is applied across it. It is also pyroelectric and will produce a
voltage in response to heat changes.
It first came out of Penwalt Corp. in about 1985, and AMP bought the
rights about 10 years later, and a couple of years ago spun of MSI,
maybe like you say in the Tyco glommuck. Penwalt produced some
really excellent, fascinating technical and application manuals.
Those are probably still available on the MSI web site.
-- Tracy