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New Pvore

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  • David
    Hey, do you guys think this circuit will work? Wilf? Bruce? It seems like it should, using the inverters as buffers and the photodiodes to create a bias- any
    Message 1 of 12 , Feb 14, 2002
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      Hey, do you guys think this circuit will work? Wilf?
      Bruce? It seems like it should, using the inverters
      as buffers and the photodiodes to create a bias- any
      feedback? it's only 3 parts.

      Thanks,
      David

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    • David
      I forgot to add the schematic- here it is. David ... __________________________________________________ Do You Yahoo!? Send FREE Valentine eCards with Yahoo!
      Message 2 of 12 , Feb 14, 2002
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        I forgot to add the schematic- here it is.

        David
        --- David <dsg123456789@...> wrote:
        > Hey, do you guys think this circuit will work?
        > Wilf?
        > Bruce? It seems like it should, using the inverters
        > as buffers and the photodiodes to create a bias- any
        > feedback? it's only 3 parts.
        >
        > Thanks,
        > David
        >
        > __________________________________________________
        > Do You Yahoo!?
        > Send FREE Valentine eCards with Yahoo! Greetings!
        > http://greetings.yahoo.com
        >


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      • César Blum Silveira
        This is like an iVore, but more complex :-). I ve designeed this too once, thinking it was a kinda new pvore. César ... From: David To: beam@yahoogroups.com
        Message 3 of 12 , Feb 14, 2002
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          This is like an iVore, but more complex :-). I've designeed this too once, thinking it was a kinda new pvore.
           
          César
          ----- Original Message -----
          From: David
          Sent: Thursday, February 14, 2002 4:09 PM
          Subject: Re: [beam] New Pvore

          I forgot to add the schematic- here it is.

          David
          --- David <dsg123456789@...> wrote:
          > Hey, do you guys think this circuit will work?
          > Wilf?
          > Bruce?  It seems like it should, using the inverters
          > as buffers and the photodiodes to create a bias- any
          > feedback?  it's only 3 parts.
          >
          > Thanks,
          > David
          >
          > __________________________________________________
          > Do You Yahoo!?
          > Send FREE Valentine eCards with Yahoo! Greetings!
          > http://greetings.yahoo.com
          >


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        • Wilf Rigter
          The PDs should be reversed. I recommend a small cap from the midpoint of the PDs to the second inverter output. It will work fine as is but the left inverter
          Message 4 of 12 , Feb 14, 2002
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            The PDs should be reversed. I recommend a small cap from the midpoint of the
            PDs to the second inverter output. It will work fine as is but the left
            inverter can be omitted.

            wilf


            -----Original Message-----
            From: David [mailto:dsg123456789@...]
            Sent: Thursday, February 14, 2002 11:09 AM
            To: beam@yahoogroups.com
            Subject: Re: [beam] New Pvore


            I forgot to add the schematic- here it is.

            David
            --- David <dsg123456789@...> wrote:
            > Hey, do you guys think this circuit will work?
            > Wilf?
            > Bruce? It seems like it should, using the inverters
            > as buffers and the photodiodes to create a bias- any
            > feedback? it's only 3 parts.
            >
            > Thanks,
            > David
            >
            > __________________________________________________
            > Do You Yahoo!?
            > Send FREE Valentine eCards with Yahoo! Greetings!
            > http://greetings.yahoo.com
            >


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          • David
            Could you draw that up please? Also, what s the iVore schcematic? Thanks, David ... __________________________________________________ Do You Yahoo!? Send
            Message 5 of 12 , Feb 14, 2002
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              Could you draw that up please? Also, what's the iVore
              schcematic?

              Thanks,
              David
              --- Wilf Rigter <wilf.rigter@...> wrote:
              > The PDs should be reversed. I recommend a small cap
              > from the midpoint of the
              > PDs to the second inverter output. It will work fine
              > as is but the left
              > inverter can be omitted.
              >
              > wilf
              >
              >
              > -----Original Message-----
              > From: David [mailto:dsg123456789@...]
              > Sent: Thursday, February 14, 2002 11:09 AM
              > To: beam@yahoogroups.com
              > Subject: Re: [beam] New Pvore
              >
              >
              > I forgot to add the schematic- here it is.
              >
              > David
              > --- David <dsg123456789@...> wrote:
              > > Hey, do you guys think this circuit will work?
              > > Wilf?
              > > Bruce? It seems like it should, using the
              > inverters
              > > as buffers and the photodiodes to create a bias-
              > any
              > > feedback? it's only 3 parts.
              > >
              > > Thanks,
              > > David
              > >
              > > __________________________________________________
              > > Do You Yahoo!?
              > > Send FREE Valentine eCards with Yahoo! Greetings!
              > > http://greetings.yahoo.com
              > >
              >
              >
              > __________________________________________________
              > Do You Yahoo!?
              > Send FREE Valentine eCards with Yahoo! Greetings!
              > http://greetings.yahoo.com
              >
              > To unsubscribe from this group, send an email to:
              > beam-unsubscribe@egroups.com
              >
              >
              >
              > Your use of Yahoo! Groups is subject to
              > http://docs.yahoo.com/info/terms/
              >
              >


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            • Wilf Rigter
              Here you are. These 3 circuits have the same logic and behavior. Your configuration isolates the light sensing circuit from the motors. It should give a nice
              Message 6 of 12 , Feb 14, 2002
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                Here you are. These 3 circuits have the same logic and behavior. Your
                configuration isolates the light sensing circuit from the motors. It should
                give a nice crispy (efficient) switching action. Note that 3 inverters are
                wired in parallel for each of motor drivers.

                wilf

                -----Original Message-----
                From: David
                To: beam@yahoogroups.com
                Sent: 2/14/02 5:13 PM
                Subject: RE: [beam] New Pvore

                Could you draw that up please? Also, what's the iVore
                schcematic?

                Thanks,
                David
                --- Wilf Rigter <wilf.rigter@...> wrote:
                > The PDs should be reversed. I recommend a small cap
                > from the midpoint of the
                > PDs to the second inverter output. It will work fine
                > as is but the left
                > inverter can be omitted.
                >
                > wilf
                >
                >
                > -----Original Message-----
                > From: David [mailto:dsg123456789@...]
                > Sent: Thursday, February 14, 2002 11:09 AM
                > To: beam@yahoogroups.com
                > Subject: Re: [beam] New Pvore
                >
                >
                > I forgot to add the schematic- here it is.
                >
                > David
                > --- David <dsg123456789@...> wrote:
                > > Hey, do you guys think this circuit will work?
                > > Wilf?
                > > Bruce? It seems like it should, using the
                > inverters
                > > as buffers and the photodiodes to create a bias-
                > any
                > > feedback? it's only 3 parts.
                > >
                > > Thanks,
                > > David
                > >
                > > __________________________________________________
                > > Do You Yahoo!?
                > > Send FREE Valentine eCards with Yahoo! Greetings!
                > > http://greetings.yahoo.com
                > >
                >
                >
                > __________________________________________________
                > Do You Yahoo!?
                > Send FREE Valentine eCards with Yahoo! Greetings!
                > http://greetings.yahoo.com
                >
                > To unsubscribe from this group, send an email to:
                > beam-unsubscribe@egroups.com
                >
                >
                >
                > Your use of Yahoo! Groups is subject to
                > http://docs.yahoo.com/info/terms/
                >
                >


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              • Bryan Yeung
                Could someone please explain how this works? Bryan ... name=simple pvore1.gif __________________________________________________ Do You Yahoo!? Got something
                Message 7 of 12 , Feb 15, 2002
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                  Could someone please explain how this works?

                  Bryan

                  --- Wilf Rigter <wilf.rigter@...> wrote:
                  >
                  > Here you are. These 3 circuits have the same logic
                  > and behavior. Your
                  > configuration isolates the light sensing circuit
                  > from the motors. It should
                  > give a nice crispy (efficient) switching action.
                  > Note that 3 inverters are
                  > wired in parallel for each of motor drivers.
                  >
                  > wilf
                  >
                  > -----Original Message-----
                  > From: David
                  > To: beam@yahoogroups.com
                  > Sent: 2/14/02 5:13 PM
                  > Subject: RE: [beam] New Pvore
                  >
                  > Could you draw that up please? Also, what's the
                  > iVore
                  > schcematic?
                  >
                  > Thanks,
                  > David
                  > --- Wilf Rigter <wilf.rigter@...> wrote:
                  > > The PDs should be reversed. I recommend a small
                  > cap
                  > > from the midpoint of the
                  > > PDs to the second inverter output. It will work
                  > fine
                  > > as is but the left
                  > > inverter can be omitted.
                  > >
                  > > wilf
                  > >
                  > >
                  > > -----Original Message-----
                  > > From: David [mailto:dsg123456789@...]
                  > > Sent: Thursday, February 14, 2002 11:09 AM
                  > > To: beam@yahoogroups.com
                  > > Subject: Re: [beam] New Pvore
                  > >
                  > >
                  > > I forgot to add the schematic- here it is.
                  > >
                  > > David
                  > > --- David <dsg123456789@...> wrote:
                  > > > Hey, do you guys think this circuit will work?
                  > > > Wilf?
                  > > > Bruce? It seems like it should, using the
                  > > inverters
                  > > > as buffers and the photodiodes to create a bias-
                  > > any
                  > > > feedback? it's only 3 parts.
                  > > >
                  > > > Thanks,
                  > > > David
                  > > >
                  > > >
                  > __________________________________________________
                  > > > Do You Yahoo!?
                  > > > Send FREE Valentine eCards with Yahoo!
                  > Greetings!
                  > > > http://greetings.yahoo.com
                  > > >
                  > >
                  > >
                  > > __________________________________________________
                  > > Do You Yahoo!?
                  > > Send FREE Valentine eCards with Yahoo! Greetings!
                  > > http://greetings.yahoo.com
                  > >
                  > > To unsubscribe from this group, send an email to:
                  > > beam-unsubscribe@egroups.com
                  > >
                  > >
                  > >
                  > > Your use of Yahoo! Groups is subject to
                  > > http://docs.yahoo.com/info/terms/
                  > >
                  > >
                  >
                  >
                  > __________________________________________________
                  > Do You Yahoo!?
                  > Send FREE Valentine eCards with Yahoo! Greetings!
                  > http://greetings.yahoo.com
                  >
                  >
                  > To unsubscribe from this group, send an email to:
                  > beam-unsubscribe@egroups.com
                  >
                  >
                  >
                  > Your use of Yahoo! Groups is subject to
                  > http://docs.yahoo.com/info/terms/
                  >
                  >
                  >

                  > ATTACHMENT part 2 application/octet-stream
                  name=simple pvore1.gif



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                • conan_the_librarian_2002
                  Gang, Somehow this really sounded familiar when I first saw it -- turns out David has reinvented (simplified, really) one of Wilf s circuits from three years
                  Message 8 of 12 , Feb 15, 2002
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                    Gang,

                    Somehow this really sounded familiar when I first saw it -- turns out
                    David has reinvented (simplified, really) one of Wilf's circuits from
                    three years back. I have it all written up now:

                    http://library.solarbotics.net/circuits/bot_popper_240.html

                    Conan

                    --- In beam@y..., Wilf Rigter <wilf.rigter@p...> wrote:
                    >
                    > Here you are. These 3 circuits have the same logic and behavior.
                    Your
                    > configuration isolates the light sensing circuit from the motors.
                    It should
                    > give a nice crispy (efficient) switching action. Note that 3
                    inverters are
                    > wired in parallel for each of motor drivers.
                    >
                    > wilf
                    >
                    > -----Original Message-----
                    > From: David
                    > To: beam@y...
                    > Sent: 2/14/02 5:13 PM
                    > Subject: RE: [beam] New Pvore
                    >
                    > Could you draw that up please? Also, what's the iVore
                    > schcematic?
                    >
                    > Thanks,
                    > David
                    > --- Wilf Rigter <wilf.rigter@p...> wrote:
                    > > The PDs should be reversed. I recommend a small cap
                    > > from the midpoint of the
                    > > PDs to the second inverter output. It will work fine
                    > > as is but the left
                    > > inverter can be omitted.
                    > >
                    > > wilf
                    > >
                    > >
                    > > -----Original Message-----
                    > > From: David [mailto:dsg123456789@y...]
                    > > Sent: Thursday, February 14, 2002 11:09 AM
                    > > To: beam@y...
                    > > Subject: Re: [beam] New Pvore
                    > >
                    > >
                    > > I forgot to add the schematic- here it is.
                    > >
                    > > David
                    > > --- David <dsg123456789@y...> wrote:
                    > > > Hey, do you guys think this circuit will work?
                    > > > Wilf?
                    > > > Bruce? It seems like it should, using the
                    > > inverters
                    > > > as buffers and the photodiodes to create a bias-
                    > > any
                    > > > feedback? it's only 3 parts.
                    > > >
                    > > > Thanks,
                    > > > David

                    -----------------------------------------------------------------
                    Conan the Librarian (conan.librarian@...)
                    Custodian of the BEAM Reference Library at http://solarbotics.net
                  • David
                    Wilf- What are the capacitors for? And how exactly does a capacitor work? Can they conduct between there two terminals? B/c I only understood the R/C time
                    Message 9 of 12 , Feb 15, 2002
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                      Wilf-
                      What are the capacitors for? And how exactly does a
                      capacitor work? Can they conduct between there two
                      terminals? B/c I only understood the R/C time
                      constants. And also, is there any other value then
                      100pf for the caps? Like, .22uf or .47uf?

                      Thanks,
                      David

                      P.S. I couldn't get my circuit to respond to light, so
                      i cut off the pd's and then left the first inverter
                      floating, it went to ground and then when i tapped
                      positive to the first inverter the other motor would
                      spin for a short time even though the input was
                      floating then it would switch back. Is this like a
                      volitile memory device?
                      --- Wilf Rigter <wilf.rigter@...> wrote:
                      >
                      > Here you are. These 3 circuits have the same logic
                      > and behavior. Your
                      > configuration isolates the light sensing circuit
                      > from the motors. It should
                      > give a nice crispy (efficient) switching action.
                      > Note that 3 inverters are
                      > wired in parallel for each of motor drivers.
                      >
                      > wilf
                      >
                      > -----Original Message-----
                      > From: David
                      > To: beam@yahoogroups.com
                      > Sent: 2/14/02 5:13 PM
                      > Subject: RE: [beam] New Pvore
                      >
                      > Could you draw that up please? Also, what's the
                      > iVore
                      > schcematic?
                      >
                      > Thanks,
                      > David
                      > --- Wilf Rigter <wilf.rigter@...> wrote:
                      > > The PDs should be reversed. I recommend a small
                      > cap
                      > > from the midpoint of the
                      > > PDs to the second inverter output. It will work
                      > fine
                      > > as is but the left
                      > > inverter can be omitted.
                      > >
                      > > wilf
                      > >
                      > >
                      > > -----Original Message-----
                      > > From: David [mailto:dsg123456789@...]
                      > > Sent: Thursday, February 14, 2002 11:09 AM
                      > > To: beam@yahoogroups.com
                      > > Subject: Re: [beam] New Pvore
                      > >
                      > >
                      > > I forgot to add the schematic- here it is.
                      > >
                      > > David
                      > > --- David <dsg123456789@...> wrote:
                      > > > Hey, do you guys think this circuit will work?
                      > > > Wilf?
                      > > > Bruce? It seems like it should, using the
                      > > inverters
                      > > > as buffers and the photodiodes to create a bias-
                      > > any
                      > > > feedback? it's only 3 parts.
                      > > >
                      > > > Thanks,
                      > > > David
                      > > >
                      > > >
                      > __________________________________________________
                      > > > Do You Yahoo!?
                      > > > Send FREE Valentine eCards with Yahoo!
                      > Greetings!
                      > > > http://greetings.yahoo.com
                      > > >
                      > >
                      > >
                      > > __________________________________________________
                      > > Do You Yahoo!?
                      > > Send FREE Valentine eCards with Yahoo! Greetings!
                      > > http://greetings.yahoo.com
                      > >
                      > > To unsubscribe from this group, send an email to:
                      > > beam-unsubscribe@egroups.com
                      > >
                      > >
                      > >
                      > > Your use of Yahoo! Groups is subject to
                      > > http://docs.yahoo.com/info/terms/
                      > >
                      > >
                      >
                      >
                      > __________________________________________________
                      > Do You Yahoo!?
                      > Send FREE Valentine eCards with Yahoo! Greetings!
                      > http://greetings.yahoo.com
                      >
                      >
                      > To unsubscribe from this group, send an email to:
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                      >
                      >
                      >
                      > Your use of Yahoo! Groups is subject to
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                      >
                      >
                      >

                      > ATTACHMENT part 2 application/octet-stream
                      name=simple pvore1.gif



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                    • David
                      Wilf- why are the pd s reverse biased? Thanks, David ... name=simple pvore1.gif __________________________________________________ Do You Yahoo!? Yahoo! Sports
                      Message 10 of 12 , Feb 16, 2002
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                        Wilf- why are the pd's reverse biased?

                        Thanks,
                        David
                        --- Wilf Rigter <wilf.rigter@...> wrote:
                        >
                        > Here you are. These 3 circuits have the same logic
                        > and behavior. Your
                        > configuration isolates the light sensing circuit
                        > from the motors. It should
                        > give a nice crispy (efficient) switching action.
                        > Note that 3 inverters are
                        > wired in parallel for each of motor drivers.
                        >
                        > wilf
                        >
                        > -----Original Message-----
                        > From: David
                        > To: beam@yahoogroups.com
                        > Sent: 2/14/02 5:13 PM
                        > Subject: RE: [beam] New Pvore
                        >
                        > Could you draw that up please? Also, what's the
                        > iVore
                        > schcematic?
                        >
                        > Thanks,
                        > David
                        > --- Wilf Rigter <wilf.rigter@...> wrote:
                        > > The PDs should be reversed. I recommend a small
                        > cap
                        > > from the midpoint of the
                        > > PDs to the second inverter output. It will work
                        > fine
                        > > as is but the left
                        > > inverter can be omitted.
                        > >
                        > > wilf
                        > >
                        > >
                        > > -----Original Message-----
                        > > From: David [mailto:dsg123456789@...]
                        > > Sent: Thursday, February 14, 2002 11:09 AM
                        > > To: beam@yahoogroups.com
                        > > Subject: Re: [beam] New Pvore
                        > >
                        > >
                        > > I forgot to add the schematic- here it is.
                        > >
                        > > David
                        > > --- David <dsg123456789@...> wrote:
                        > > > Hey, do you guys think this circuit will work?
                        > > > Wilf?
                        > > > Bruce? It seems like it should, using the
                        > > inverters
                        > > > as buffers and the photodiodes to create a bias-
                        > > any
                        > > > feedback? it's only 3 parts.
                        > > >
                        > > > Thanks,
                        > > > David
                        > > >
                        > > >
                        > __________________________________________________
                        > > > Do You Yahoo!?
                        > > > Send FREE Valentine eCards with Yahoo!
                        > Greetings!
                        > > > http://greetings.yahoo.com
                        > > >
                        > >
                        > >
                        > > __________________________________________________
                        > > Do You Yahoo!?
                        > > Send FREE Valentine eCards with Yahoo! Greetings!
                        > > http://greetings.yahoo.com
                        > >
                        > > To unsubscribe from this group, send an email to:
                        > > beam-unsubscribe@egroups.com
                        > >
                        > >
                        > >
                        > > Your use of Yahoo! Groups is subject to
                        > > http://docs.yahoo.com/info/terms/
                        > >
                        > >
                        >
                        >
                        > __________________________________________________
                        > Do You Yahoo!?
                        > Send FREE Valentine eCards with Yahoo! Greetings!
                        > http://greetings.yahoo.com
                        >
                        >
                        > To unsubscribe from this group, send an email to:
                        > beam-unsubscribe@egroups.com
                        >
                        >
                        >
                        > Your use of Yahoo! Groups is subject to
                        > http://docs.yahoo.com/info/terms/
                        >
                        >
                        >

                        > ATTACHMENT part 2 application/octet-stream
                        name=simple pvore1.gif



                        __________________________________________________
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                      • Wilf Rigter
                        The monocore capacitor is for positive feedback for fast switching between the two motors and to slow down and avoid high frequency oscillations. With average
                        Message 11 of 12 , Feb 16, 2002
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                          The monocore capacitor is for positive feedback for fast switching between
                          the two motors and to slow down and avoid high frequency oscillations. With
                          average light and 100pf, the frequency is 1KHz so there is a kind of
                          vibration as each motor rapidly turns on and off. The overall effect is
                          continuous rotation of both motors while moving straight towards the
                          balanced light condition. Larger values will slow the oscillations so that
                          each motor stays on longer (1 second on/1 second off)and the motion is a
                          "waddle" or even a twirling motion. With so much "overshoot" the motion will
                          be somewhat random but the average direction should be towards balanced
                          light. Try 1000pf or 0.01 uF for more purposeful motion.

                          If you connected the PDs in the direction shown in your first schematic they
                          are probably blown. That is because they act like two diodes in series
                          across the powere supply and the with a 3V battery they would last less than
                          a second before overheating and self-destructing.

                          The input of a CMOS gate has a small "stray" capacitance to ground and Vcc.
                          If the input is left floating the cap will be charged and discharged by
                          tapping the input pin to + and Gnd. Since there is almost no input current,
                          the input capacitance will maintain it's charge state and therefore the
                          inverter will keep its logic state, for quite a long time. It is a form of
                          short term memory.

                          wilf


                          -----Original Message-----
                          From: David [mailto:dsg123456789@...]
                          Sent: Friday, February 15, 2002 3:16 PM
                          To: beam@yahoogroups.com
                          Subject: RE: [beam] New Pvore


                          Wilf-
                          What are the capacitors for? And how exactly does a
                          capacitor work? Can they conduct between there two
                          terminals? B/c I only understood the R/C time
                          constants. And also, is there any other value then
                          100pf for the caps? Like, .22uf or .47uf?

                          Thanks,
                          David

                          P.S. I couldn't get my circuit to respond to light, so
                          i cut off the pd's and then left the first inverter
                          floating, it went to ground and then when i tapped
                          positive to the first inverter the other motor would
                          spin for a short time even though the input was
                          floating then it would switch back. Is this like a
                          volitile memory device?
                        • David
                          Thanks David ... __________________________________________________ Do You Yahoo!? Yahoo! Sports - Coverage of the 2002 Olympic Games http://sports.yahoo.com
                          Message 12 of 12 , Feb 16, 2002
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                            Thanks

                            David
                            --- Wilf Rigter <wilf.rigter@...> wrote:
                            >
                            > The monocore capacitor is for positive feedback for
                            > fast switching between
                            > the two motors and to slow down and avoid high
                            > frequency oscillations. With
                            > average light and 100pf, the frequency is 1KHz so
                            > there is a kind of
                            > vibration as each motor rapidly turns on and off.
                            > The overall effect is
                            > continuous rotation of both motors while moving
                            > straight towards the
                            > balanced light condition. Larger values will slow
                            > the oscillations so that
                            > each motor stays on longer (1 second on/1 second
                            > off)and the motion is a
                            > "waddle" or even a twirling motion. With so much
                            > "overshoot" the motion will
                            > be somewhat random but the average direction should
                            > be towards balanced
                            > light. Try 1000pf or 0.01 uF for more purposeful
                            > motion.
                            >
                            > If you connected the PDs in the direction shown in
                            > your first schematic they
                            > are probably blown. That is because they act like
                            > two diodes in series
                            > across the powere supply and the with a 3V battery
                            > they would last less than
                            > a second before overheating and self-destructing.
                            >
                            > The input of a CMOS gate has a small "stray"
                            > capacitance to ground and Vcc.
                            > If the input is left floating the cap will be
                            > charged and discharged by
                            > tapping the input pin to + and Gnd. Since there is
                            > almost no input current,
                            > the input capacitance will maintain it's charge
                            > state and therefore the
                            > inverter will keep its logic state, for quite a long
                            > time. It is a form of
                            > short term memory.
                            >
                            > wilf
                            >
                            >
                            > -----Original Message-----
                            > From: David [mailto:dsg123456789@...]
                            > Sent: Friday, February 15, 2002 3:16 PM
                            > To: beam@yahoogroups.com
                            > Subject: RE: [beam] New Pvore
                            >
                            >
                            > Wilf-
                            > What are the capacitors for? And how exactly does a
                            > capacitor work? Can they conduct between there two
                            > terminals? B/c I only understood the R/C time
                            > constants. And also, is there any other value then
                            > 100pf for the caps? Like, .22uf or .47uf?
                            >
                            > Thanks,
                            > David
                            >
                            > P.S. I couldn't get my circuit to respond to light,
                            > so
                            > i cut off the pd's and then left the first inverter
                            > floating, it went to ground and then when i tapped
                            > positive to the first inverter the other motor would
                            > spin for a short time even though the input was
                            > floating then it would switch back. Is this like a
                            > volitile memory device?
                            >


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