Alt-BEAM Archive

Message #02505



To: "BEAM Mail" beam@corp.sgi.com
From: "Nigel Joyce" nigel.joyce@qr.com.au
Date: Tue, 20 Apr 1999 11:01:55 +1000
Subject: [alt-beam] Fw: component identifcation and SE Comparison



> Thanks Wilf,
> I was going to use a 1000uF cap for the timing cap on
> the LM3909 circuit and a 4700uF cap for storage. Sound right?
>
> With the NPN, PNP transistors, I am looking for a good combination that
will
> power a photopopper off a calculator solar panel, as these don't give out
> much current (I think) and it will fit in the screen area of the pager,
and
> I cannot locate 1381 components here in Australia.(yet)
>
> Can LM3909 SE's be used in photopoppers? How would you wire up the eyes?
>
> [snip from below]
> > > >
> > > > > On another note, I am building my first photopopper in the case of
1
> > > > > of the pagers as a tribute to the source of these great motors.
A
> > > > > calculator solar panel will fit perfectly where the LCD screen
was.
> so
> > > > > the only visible parts will be the motor shafts and the holes
where
> > > > > the eyes get the light. What sort of Voltage and Current can I
> expect
> > > > > from a calculator solar cell? I've read that a 1381 SE needs
about
> > > > > 3v, is there a SE design that uses less?
> > > >
> > > > I only use calcuslator cells cause that's all I can get. They're
> great,
> > > > usually put out about 2.8 volts. I use FLED SE's because they
trigger
> at
> > > > around 2.1v, but aren't as effecient as the 1381's. You can get
1381's
> > > > that will trigger at 2.1v, so yes, you can use your cells with a
1381
> > > > SE.
>
> thanks &
> Blue Skies
> ---Buzz---
>
>
> > An LM3909 SE would work ok although it needs quite a bit of current.
Want
> me
> > to design one for you?
> > 2N3906 is a PNP small signal transistor, almost any other small signal
> PNP
> > is the same. As a rule for SE appliactions you need sensitive devices so
> > look for HFE 100-300 at 10mA (for low current apps) For a little higher
> > current use a 2N2907A PNP transistor and it's equivalent NPN, the
> 2N2222A.
> >
> > enjoy
> >
> > Wilf Rigter mailto:wilf.rigter@powertech.bc.ca
> > tel: (604)590-7493
> > fax: (604)590-3411
> >
> > > -----Original Message-----
> > > From: Nigel Joyce [SMTP:nigel.joyce@qr.com.au]
> > > Sent: Wednesday, April 14, 1999 4:53 PM
> > > To: BEAM Mail
> > > Subject: Re: component identifcation and SE Comparison
> > >
> > > Thanks Kyle for the info, I was hoping for a bit more about this bit
> here
> > > from the rest of the board.
> > >
> > > > > I just got my first electronics catalogue from
> > > > > dick smith electronics, (our local electronics store, also stocks
> the
> > > > > cybug and higher function add-ons) and I cannot find the 1381's or
> the
> > > > > 3906's in it, the 3904's are there as well as a heap of other
stuff
> > > > > but as I am new to this stuff, are there other names these
> components
> > > > > are known as?
> > >
> > > Is there equivalent transistors for the
> > > a. 3906 PNP's = =
?
> > > b. 3904 NPN's = 2n2222 ? = ?
> > > c. 1381 Voltage Detectors = ?
> > >
> > >
> > > Has there been a discussion previously on the advantages/disadvantages
> of
> > > each of the SE's?
> > > I got a couple of the LM3909's from the shop, Yet to build SE's from
> them
> > > though,
> > >
> > > I don't understand why they aren't used more, they seem very simple to
> me,
> > > and perhaps smaller? easier to tune?
> > >
> > > With regards to the standard solarbotics photopopper circuit, Isn't
> there
> > > a
> > > bit of redundancy there? I mean, all it is 2 SE's that are biased so
> the
> > > 1
> > > receiving less light fires first right?
> > >
> > > Wouldn't it be simpler to have just 1 SE and then have some sort of
> simple
> > > circuit to decide which side gets the current. Is there any sort of
> chip
> > > that flips a switch depending on which input has a larger/smaller
> > > resistance?
> > >
> > > I am new to this so I still don't understand what is possible and what
> is
> > > not possible. I guess it's the programmer in me trying to remove the
> > > redundancy.
> > > Blue Skies
> > > ---Buzz---
> > >
> > > I didn't just kiss death, I slipped it the tongue!
> > >
> > > nigel.joyce@usa.net
> > >
> > > > > Hey everyone,
> > > > > I just got my first electronics catalogue from
> > > > > dick smith electronics, (our local electronics store, also stocks
> the
> > > > > cybug and higher function add-ons) and I cannot find the 1381's or
> the
> > > > > 3906's in it, the 3904's are there as well as a heap of other
stuff
> > > > > but as I am new to this stuff, are there other names these
> components
> > > > > are known as?
> > > >
> > > >
> > > > Hmm, don't know about this. They probably don't carry the 1381
> though,
> > > > you'll most likely have to get it from DigiKey.
> > > >
> > > >
> > > > > Also, I have sofar pulled apart 1 old computer, 1 old video
player,
> > > > > about 20 old pagers (16 great motors) and a bunch of other old
> > > > > electronics that had been collecting dust under the house (I knew
> > > > > there was a reason I didn't chuck it all out). anyway, I have a
> bunch
> > > > > of IC's that are marked with 74****** something, something. I was
> > > > > wondering which ones of these are handy for BEAM?
> > > >
> > > > These are useful:
> > > > 74**14 - Microcore
> > > > 74**245 - Microcore
> > > > 74**00 - Suneater 2,3
> > > > 74**02 - Suneater 3
> > > >
> > > > ** = hc, als, hct, etc.... Soem are better than others, check the
> > > > schematics.
> > > > Info on the Suneaters series (They're great) can be found on Steven
> > > > Bolt's (He's cool) site:
> > > > http://www.xs4all.nl/~sbolt/e-index.html
> > > >
> > > > It's on there somewhere....
> > > >
> > > > > Also, I pulled apart a mouse that was stuffed, what do the led's
in
> > > > > them detect, and emit? is it IR?
> > > >
> > > > >From what I know, yes.
> > > >
> > > > > On another note, I am building my first photopopper in the case of
1
> > > > > of the pagers as a tribute to the source of these great motors.
A
> > > > > calculator solar panel will fit perfectly where the LCD screen
was.
> so
> > > > > the only visible parts will be the motor shafts and the holes
where
> > > > > the eyes get the light. What sort of Voltage and Current can I
> expect
> > > > > from a calculator solar cell? I've read that a 1381 SE needs
about
> > > > > 3v, is there a SE design that uses less?
> > > >
> > > > I only use calcuslator cells cause that's all I can get. They're
> great,
> > > > usually put out about 2.8 volts. I use FLED SE's because they
trigger
> at
> > > > around 2.1v, but aren't as effecient as the 1381's. You can get
1381's
> > > > that will trigger at 2.1v, so yes, you can use your cells with a
1381
> > > > SE.
> > > > Adios,
> > > > Kyle
> > > >
> > > > -
> > > > "If you can..."
>


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