Alt-BEAM Archive

Message #11827



To: beam@sgiblab.sgi.com
From: Ben Hitchcock beh01@uow.edu.au
Date: Wed, 15 Mar 2000 11:08:22 +1100 (EST)
Subject: [alt-beam] Re: 1000k pots


This message is being sent for the second time. Apologies if you get it
twice. I wonder what happens to all the e-mails that get sent but don't
go to where they're going? Do they end up in the electronic equivalent
of the 'back store'?

Anyway,

> Alas and alack, the Shack doesn't sell photodiodes. In most apps, the
> resistors will not work. Are you making a FLED pvore? Ben Hitchcock's
(sp)
> works without doiodes. Try that. URL?
> (http://wollongong.apana.au.com/~ben)?? I dunno.

Close but no cigar.
http://wollongong.apana.org.au/~ben/fred/ should get you to the main page
for that solar engine.

> > Are 1000k pots too high to make a standard photovore? I couldn't find
any
> > small 100k's at radio shack, I think they were all out.

I would think that 100k would work fine for your purposes. You may need
to
lower the 0.22 uF caps to 0.022, but I would try it regardless.

> >Also, can
> > photoresistors be used in the place of photodiodes? I got something at
> radio
> > shack called cadmium photocells. I'm not sure if they are the same as
the
> > photodiodes or resistors? Any help would be appreciated.

The way to make a popper be affected by light is to make a pair of solar
engines, where a component in the solar engine is affected by light.
It doesn't matter what the component is: it could be a photocell, a
photodiode,
a solar panel, a FLED, a photoresistor, it doesn't matter. Just so long
as a
change in light level equals a change in the characteristics of the SE,
then the
popper will either turn towards or go away or scuttle sideways in relation
to
the brightest light source.

I used this to my advantage in the FRED popper. I knew that FLEDs are
affected
by changes in ambient light, so I made two solar engines, hooked them up
to the
one solar panel and cap, added some motors and some wire and voila! Some
people
on the list have made a popper out of a pair of two-transistor solar
engines,
replacing one of the transistors on each side with a phototransistor!

In answer to your question: Yes you can use photoresistors. You can also
use
your cadmium photocells, and I bet you could use standard red LEDs (with a
clear
case) as well.

Go forth and experiment!

Ben



11828 Tue, 14 Mar 2000 16:37:23 -0800 [alt-beam] Re: Beam Web Index - circuits section Beam mailing list Bruce Robinson Yes, it's here already.

Thanks to a little goading, and a LOT of research on Justin's part, the
new circuit section on the BEAM Web Index is up and running. This
section may need to be reorganized as it grows, but it's certainly a
good start. All the links have been checked, and appropriate credit
given (to the best of my ability to find out).

http://www3.telus.net/rfws/bwi/index.html

I also added a link in the Walker section to Robert Stein's tutorial on
making a gearmotor out of a walkman motor and a Kitchen timer unit.

As always, let me know about anything that isn't working right.

Regards,
Bruce



11829 Tue, 14 Mar 2000 17:07:18 -0800 (PST) [alt-beam] Re: possible motors beam@sgiblab.sgi.com Daniel Grace I'm in Alabama, way on the other end of the US (but
not nearly as far as some people on this list), and we
have general stores, but we don't call them liqueur
stores. Anyway, I know what you mean now. Just for an
update to this list:

I have a friend in a gas station, and she agrees with
me, they're gone off the face of the earth! I went to
at least 20 stores today, just looking for those (I
did wind up going to the rat shack and getting the
rest of what I need for the head, but still no decent
motors!), and they're gone! I'll try a web search.
Maybe I can locate the manufacturer. Anyone else able
to find these? Anyone trying?

~Daniel

--- Timothy Flytch wrote:
> well Daniel... when I say "liqueur store" I mean the
> little corner store
> that sells candy,ice cream, soda, beer, and wine...
> I don't know were you
> are... but here on the central coast of California
> they are everywhere...
>
> Timothy...
>
> >I _just_ turned 16, so I don't know how to get to
> most
> >of these places, and definately can't check the
> >liqueur store! thanks for the suggestions!
> >
> >~Daniel
> >
> >--- Timothy Flytch wrote:
> > > There sold by private venders... so like all
> things
> > > at wally word sometimes
> > > they just don't have them and may never again...
> try
> > > your local liqueur
> > > store... I've seen them in the grocery stores
> too...
> > > Albertsons... longs...
> > > K-mart... and payless...
> > >
> > > Timothy...
> > >
> > > >
> > > >I looked for the rotating suckers at the store
> > > today.
> > > >Wal-Mart doesn't carry them any more! Does
> anyone
> > > know
> > > >where they can be found?
> > > >
> > > >~Daniel
> > > >
> > > >=====
> > > >ICQ # 39402143
> > >
> >__________________________________________________
> > > >Do You Yahoo!?
> > > >Talk to your friends online with Yahoo!
> Messenger.
> > > >http://im.yahoo.com
> > >
> > >
>
>______________________________________________________
> > > Get Your Private, Free Email at
> > > http://www.hotmail.com
> > >
> > >
> >
> >=====
> >ICQ # 39402143
> >__________________________________________________
> >Do You Yahoo!?
> >Talk to your friends online with Yahoo! Messenger.
> >http://im.yahoo.com
>
>
______________________________________________________
>


11830 Tue, 14 Mar 2000 20:01:34 EST [alt-beam] Re: Beam Web Index - circuits section beam@sgiblab.sgi.com BUDSCOTT@aol.com That's pretty awesome, that has just about all the circuits and links that
anybody could possibly need for most robots. Hope the web page gets some more
hits for that!

-Spencer



11831 Tue, 14 Mar 2000 20:02:16 EST [alt-beam] Phototroph observation beam@sgiblab.sgi.com BUDSCOTT@aol.com You ever really play around with the influence of color on your photorophic
robots? I found some really cool tricks to play on phototrophs, since they
are attracted to light and white stuff, i found that they will follow a long
peice of solder streched out along my desk, or any other shiny wire, the
trick is to lay out almost a shiny road. I also have been able to get my
robots to follow a white track of paper on a black surface, kinda wierd that
it works as well as it does. Ping Pong balls can also be an interesting thing
to throw out in front of a phototroph. Thought i'd just share this with
anybody who hasn't done stuff like this yet!

-Spencer



11832 Tue, 14 Mar 2000 19:54:44 EST [alt-beam] Re: Vibration sensor from Silly Slammer beam@sgiblab.sgi.com Ld5253@aol.com The shack sells a digital component that saves 20 seconds of sound for about
$20 US. A fairly small chip that could be used record( save?) any sound or
words you like. i don't know what circuitry would be needed to support it.



11833 Wed, 15 Mar 2000 07:57:27 +1100 (EST) [alt-beam] Re: 1000k pots beam@sgiblab.sgi.com Ben Hitchcock Hi,
> Alas and alack, the Shack doesn't sell photodiodes. In most apps, the
> resistors will not work. Are you making a FLED pvore? Ben Hitchcock's (sp)
> works without doiodes. Try that. URL?
> (http://wollongong.apana.au.com/~ben)?? I dunno.

Close!
http://wollongong.apana.org.au/~ben/fred/ will get you to the relevant
page.

> > Are 1000k pots too high to make a standard photovore? I couldn't find any
> > small 100k's at radio shack, I think they were all out.

If you use a 1000k pot then you might need to replace the 0.22 uF caps
with 0.022 uF. I wouldn't think that it would be necessary. My guess is
that a 1000k pot will work fine. I haven't tried it though :)

> Also, can
> > photoresistors be used in the place of photodiodes? I got something at
> radio
> > shack called cadmium photocells. I'm not sure if they are the same as the
> > photodiodes or resistors?

Pretty much anything that is affected by light will work, it will just
change the characteristics of the popper. The only function of the 'eyes'
is to make the characteristics of one solar engine different to the other.
With the standard 1381 popper circuit, more light on one side makes the
characteristics of one side different to the other side... which means
that one side turns on in preference to the other. This is used with some
clever mechanics to make the photovore turn (more or less) towards the
side that is illuminated the most.

You can create a photopopper using a pair of just about any Solar engine
circuit, so long as the characteristics are affected by the amount of
light falling on that side. For my FRED popper I used the fact that FLEDs
suck more current when in the dark to when they are illuminated. People
on the list have created photopoppers using nothing more than a pair of
two-transistor solar engines... but one of the transistors in the pair was
a phototransistor.

So in answer to your question, yes you can use those cadmium photocells.
You can also replace the eyes with photoresistors. They should work fine.

That being said, it probably won't work as well as your standard 1381
popper. My FRED popper doesn't perform as well as the 1381 popper because
in very bright light the solar engines won't fire. This is a design flaw
but I believe that the cheapness offsets any performance issues. So you
have to put heatshrink around the body of the FLED? Big deal. Any solar
engine that you experiment with will teach you a lot more about the
subject than any kit or plan will.

Go forth and experiment!

Ben



11834 Sun, 12 Mar 2000 19:44:32 -0500 Re: numeric symbol for a .1pf ceramic cap Richard Piotter
> Thanks for that info. I knew that one page had incorrect instructions.
>
> I'm glad it's working for you! Great job finding the calc's limits as
well!
>
> I should look into interfacing a Calc, a BASIC Stamp, and an Nv/Nu net
> system. Then I can justify that massive robotics section on my TI web
> page! Hehe! :)
>
>
> Jim Taylor wrote:
> >
> > Hey rich a little update on my turbo ti83 mod. It works, but it took
some
> > tinkering with values. I've gotten as low as 10pf, and as high as 47pf.
> > Currently I'm running a 15 pf cap on a switch with the original cap.
> > Everthing is working great. It is noticably faster, however I have no
> > concrete way of testing clock speed.
> > By the way I think you were correct, the TI page I was looking at was
way
> > off on the mod. The .1pf cap caused some nasty results on the LCD end,
> > which I was told; is normal when an 82, or 83 is accelerated beyond it's
> > limit of sorts. The correct cap to replace was also incorrect. It is
> > supposed to be C7.
> >
> > Thanks for your help
> >
> > James Taylor
> > "Edgar The Hate Bug"
> > URL: http://fly.to/springmeadows
> > ICQ 14888587
> > ----- Original Message -----
> > From: Richard Piotter
> > To:
> > Sent: Tuesday, February 29, 2000 3:00 PM
> > Subject: Re: numeric symbol for a .1pf ceramic cap
> >
> > > I was thinking 1pf. I spoke before (direct mail). The .1pf
instructions
> > > were from a web page that was hastily written, and does not follow the
> > > standard procedure for turboing calculators. a .1pf cap isn't even
> > > needed. As said before, wire and such can do the same task, for that
> > > particular upgrade anyway.
> > >
> > > Of course, Radio Shack don't sell .1pf caps. I was going bby memory of
> > > the original upgrade plans, that calls for a 1 pf. Oops.
> > >
> > > John Bachman wrote:
> > > >
> > > > At 10:42 AM 2/29/00 , you wrote:
> > > > >Not avaliable my foot! Even Radio Shack sels them!!!
> > > >
> > > > The question was about a 0.1pf. That is an order of magnitude from
12pf
> > or 15pf or 8pf.
> > > >
> > > > John
> > >
> > > --
> > >
> > >
> > > Richard Piotter The Richfiles Robotics & TI web page:
> > > richfile@rconnect.com http://richfiles.calc.org
> > >
> > > -- Make Money by Simply Surfing the Net or responding to E-Mail!!!
> > > -- Click below!!!
> > >
> > > http://www.alladvantage.com/go.asp?refid=ATL147
> > > http://www.spedia.net/cgi-bin/dir/tz.cgi?run=show_svc&fl=8&vid=329630
> > >
>
> --
>
>
> Richard Piotter The Richfiles Robotics & TI web page:
> richfile@rconnect.com http://richfiles.calc.org
>
> -- Make Money by Simply Surfing the Net or responding to E-Mail!!!
> -- Click below!!!
>
> http://www.alladvantage.com/go.asp?refid=ATL147
> http://www.spedia.net/cgi-bin/dir/tz.cgi?run=show_svc&fl=8&vid=329630
>

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