Alt-BEAM Archive

Message #09513



To: alt-beam@egroups.com
From: TurtleTek@aol.com
Date: Mon, 24 Jan 2000 20:09:33 EST
Subject: [alt-beam] Bob's Site


Alright, let's try this again:

Does anyone have the URL to Bob Shannon's website? If so, what is it?

Thanks..I hope.

-Brien the TurtleTek



9514 Mon, 24 Jan 2000 17:29:38 PST [alt-beam] Re: perfect motor beam@sgiblab.sgi.com "Timothy Flytcher" ers. LEGO Micromotors fit perfectly into this definintion... and
>their
>small too (1cm cubed). Get them at your nearest LEGO shop at hime
>service.... just go to www.lego.com.
I went there and could not find them... could you please give a more
specific url???
Timothy...
______________________________________________________



9515 Tue, 25 Jan 2000 12:52:58 +1100 (EST) [alt-beam] Re: Beam And IR light beam@sgiblab.sgi.com (mailing list) Ben Hitchcock Hi,

----- Forwarded message from Brad Guillot -----
I had an idea for a robot that could be activated by ir.
Think about it: a carbot that activies at night when you do any number
of things, like open the door. Even cooler is of you would use a photo
diode that actives when it detects someone's body heat.

Now for the real question-What is a relay, how does it work, and how
do you read the schematic symbol. I ask this because the only ir
transmitter receiver pair of schematics i have uses a relay. I suspect
it is like an electronic pushbutton switch, but that is a guess. any
help is welcomed

Thanks,

Brad
---

A relay is a mechanical equivalent of a transistor. It consists of a coil
of wire, an iron core, and some sort of switch arrangement. When you pass
current through the coil, the iron core moves, which pulls the switch into
a different position. There's usually a spring to push the switch back
when the current is turned off.

They're clunky, big, expensive, but they can handle large currents. For
BEAM applications, they're overkill. Transistors work much better - which
is I guesss why you're interested in replacing it. To read the schematic,
look for the coil. It will usually be drawn as a coil, but is sometimes
shown as a rectangle. The switches that
the relay controls are usually drawn right next to the coil, but they can
be drawn over on the other side of the circuit diagram even though
physically they are inside the same package! You know which relay they
belong to by looking at the labelling on them.

The sense of the switches (normally open or normally closed) is
represented
by drawing all switches in the non-operating position. So when you
energise the coil, all the switches on the diagram will change over to the
other position.

hope this helps,

Ben



9516 Monday, 24 January 2000 4:10 Re: shameless plug.... (otherwise known as hey look at my great new beam@sgiblab.sgi.com Timothy Flytcher
>With all this talk about background... I would just like everyone to know
>that yes I am one of those people who find it vary hard to read from the
>computer... I often have to cut and paste into simpletext so the computer
>can read it for me...(Bad eyes) ... I also hate it when a page uses
800x600
>or 1024x768 format.... Makes the print just too small...
>So simple and lager is better :)
>Timothy...
>
>>My site (not BEAM, so I won't post it) uses a black
>>background too, so I'll have to look into that!
>>
>>~Daniel
>
>______________________________________________________
>


9517 Mon, 24 Jan 2000 20:15:38 -0600 [alt-beam] Re: Incredible gear motors beam@sgiblab.sgi.com Scott Burns At 11:33 AM 1/25/00 +1100, you wrote:
> > Can anyone tell me the how to order a LEGO Shop-At-Home Catalogue? I
> checked
> > out the LEGO site but couldn't see anything on there which mentioned
> the shop
> > at home facilities.
>
>Elmo


Order micro motors at 800-453-4652, part number 5119. $11 including
shipping (in the US).

Scott

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