LM324 light chaser
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I'm trying to build a light chaser to compete in the trinity fire fighting
contest. I've got a uvtron sensor already, however, I want to add an
additional light detector using a photo-transistor and LM324 op-amp. I'm told
that radio shack has the photo-transistor, but I couldn't find it on the shelf
and the attendant was not help.
I'm also told that the LM324 op-amp coupled with the photo transistor is
required. Put the who mess in a black tube and scan using a servo will pin
point the fire is my plan. It turns out that the uvtron is just too sensitive
to pinpoint the fire.
With all that said, can someone help me design the circuit for this
photo-transistor LM324 op-amp light chasing circuit?
Thanks,
Dave Cousins
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contest. I've got a uvtron sensor already, however, I want to add an
additional light detector using a photo-transistor and LM324 op-amp. I'm told
that radio shack has the photo-transistor, but I couldn't find it on the shelf
and the attendant was not help.
I'm also told that the LM324 op-amp coupled with the photo transistor is
required. Put the who mess in a black tube and scan using a servo will pin
point the fire is my plan. It turns out that the uvtron is just too sensitive
to pinpoint the fire.
With all that said, can someone help me design the circuit for this
photo-transistor LM324 op-amp light chasing circuit?
Thanks,
Dave Cousins
__________________________________________________
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Get email at your own domain with Yahoo! Mail.
http://personal.mail.yahoo.com/
Comments
the 'bot or turn the sensor with a servo?
Original Message
> I'm trying to build a light chaser to compete in the trinity fire fighting
> contest. I've got a uvtron sensor already, however, I want to add an
> additional light detector using a photo-transistor and LM324 op-amp. I'm
told
> that radio shack has the photo-transistor, but I couldn't find it on the
shelf
> and the attendant was not help.
>
> I'm also told that the LM324 op-amp coupled with the photo transistor is
> required. Put the who mess in a black tube and scan using a servo will
pin
> point the fire is my plan. It turns out that the uvtron is just too
sensitive
> to pinpoint the fire.
>
> With all that said, can someone help me design the circuit for this
> photo-transistor LM324 op-amp light chasing circuit?
Have you heard of a magazine called "Robot Science & Technology" ? It is a
great magazine devoted to hobby robotics and is a wealth of information. In
the premier edition, which was about 2 years ago, there were several articles
dealing with firefighting robots and techniques for detecting flames.
One article dealt with the Hamamatsu UVtron phototube and UVtron driving
circuit. He set the sensitivity as as high as he could get it then did the
background discrimination in software. I think this article may be available
from the magazines website http://www.robotmag.com.
I hope this can help you, good luck.
Rodent wrote:
> Why not mount the UVTRON in a housing with a small vertical slit and turn
> the 'bot or turn the sensor with a servo?
>
>
Original Message
>
>
>
> > I'm trying to build a light chaser to compete in the trinity fire fighting
> > contest. I've got a uvtron sensor already, however, I want to add an
> > additional light detector using a photo-transistor and LM324 op-amp. I'm
> told
> > that radio shack has the photo-transistor, but I couldn't find it on the
> shelf
> > and the attendant was not help.
James E. Merritt N0SRB
Electrical Engineer
(H)515-733-4463
(W)515-956-7077
FAX: 515-956-2401
______________________________________________________
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exclusive NBCi electronic greeting cards.
Have you heard of a magazine called "Robot Science & Technology" ? It is a
great magazine devoted to hobby robotics and is a wealth of information. In
the premier edition, which was about 2 years ago, there were several articles
dealing with firefighting robots and techniques for detecting flames.
One article dealt with the Hamamatsu UVtron phototube and UVtron driving
circuit. He set the sensitivity as as high as he could get it then did the
background discrimination in software. I think this article may be available
from the magazines website http://www.robotmag.com.
I hope this can help you, good luck.
Rodent wrote:
> Why not mount the UVTRON in a housing with a small vertical slit and turn
> the 'bot or turn the sensor with a servo?
>
>
Original Message
>
>
>
> > I'm trying to build a light chaser to compete in the trinity fire fighting
> > contest. I've got a uvtron sensor already, however, I want to add an
> > additional light detector using a photo-transistor and LM324 op-amp. I'm
> told
> > that radio shack has the photo-transistor, but I couldn't find it on the
> shelf
> > and the attendant was not help.
James E. Merritt N0SRB
Electrical Engineer
(H)515-733-4463
(W)515-956-7077
FAX: 515-956-2401
______________________________________________________
Get free e-mail at http://www.email.com
Visit http://ecards.nbci.com to send
exclusive NBCi electronic greeting cards.
1. It's good to have a general fire indicator.
2. Scanning with the uvtron takes a long time, and if the fire is not in the
room, than a lot of time will be wasted. The general fire indicator, assures
that the fire is in the room, while the scanning is being done.
3. The uvtron is too sensitive, and the slit I tried, resulted in poor
direction indications.
4. Finally, I'm enjoying the process of learning this new op-amp circuit.
To bring you up to date, I purchase the op-amp and photo-transistor yesterday
and bread boarded it. I finally did get a circuit sketched up and I tried it
last night, but it didn't work. The op-amp is called a quad comparator. The
output is positive if pin 3 voltage is greater than pin 2 voltage. This is how
it was explained to me. If I've got it wrong than I appreciate a correction.
All help will be appreciated.
Dave Cousins
--- Rodent <daweasel@s...> wrote:
> Why not mount the UVTRON in a housing with a small vertical slit and turn
> the 'bot or turn the sensor with a servo?
>
>
Original Message
>
>
>
> > I'm trying to build a light chaser to compete in the trinity fire fighting
> > contest. I've got a uvtron sensor already, however, I want to add an
> > additional light detector using a photo-transistor and LM324 op-amp. I'm
> told
> > that radio shack has the photo-transistor, but I couldn't find it on the
> shelf
> > and the attendant was not help.
> >
> > I'm also told that the LM324 op-amp coupled with the photo transistor is
> > required. Put the who mess in a black tube and scan using a servo will
> pin
> > point the fire is my plan. It turns out that the uvtron is just too
> sensitive
> > to pinpoint the fire.
> >
> > With all that said, can someone help me design the circuit for this
> > photo-transistor LM324 op-amp light chasing circuit?
>
>
>
>
>
>
> Your use of Yahoo! Groups is subject to http://docs.yahoo.com/info/terms/
>
>
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I'm not an expert yet with this uvtron, however, I found that that the uvtron
is very cool. It will indeed detect a match lit across the room. With the
lights on or off, this device can detect the flame. It's output is a 10 ms
pulse, and my routine, modeled after a fellow who works at Acroname, uses a
FOR/NEXT routine to capture the pulse.
Now I'm working on a secondary light sensor using a photo-transistor. I'd
really appreciate any words of wisdom about the op-amp LM324. It compares two
voltages. I'm having some problems getting it to work, although it seems
straight forward. Eventually, I will mount this photo-transistor in a tube,
and mount that on a servo for sweeping the room.
I checked out the magazine web site and found the article summarys, but I don't
think I can read the article without registering. I take it that you recommend
this magazine?
Dave
--- "James E. Merritt" <jamesem@x...> wrote:
> Hi,
>
> Have you heard of a magazine called "Robot Science & Technology" ? It is a
> great magazine devoted to hobby robotics and is a wealth of information. In
> the premier edition, which was about 2 years ago, there were several articles
>
> dealing with firefighting robots and techniques for detecting flames.
>
> One article dealt with the Hamamatsu UVtron phototube and UVtron driving
> circuit. He set the sensitivity as as high as he could get it then did the
> background discrimination in software. I think this article may be available
>
> from the magazines website http://www.robotmag.com.
>
> I hope this can help you, good luck.
>
> Rodent wrote:
> > Why not mount the UVTRON in a housing with a small vertical slit and turn
> > the 'bot or turn the sensor with a servo?
> >
> >
Original Message
> >
> >
> >
> > > I'm trying to build a light chaser to compete in the trinity fire
> fighting
> > > contest.
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