Alt-BEAM Archive

Message #12427



To: beam@sgiblab.sgi.com
From: "Timothy Flytch" flytch@hotmail.com
Date: Thu, 23 Mar 2000 20:17:19 PST
Subject: [alt-beam] Re: Cricket


Me too...

Timothy...

>
>That sounds pretty cool. Could you send me the schematic?
>
>Rusty Jones
>
>email- toby503@aol.com

______________________________________________________



12428 Thu, 23 Mar 2000 23:11:10 -0700 [alt-beam] Re: Dumb newbie Q. beam@sgiblab.sgi.com Dave Hrynkiw At 03:33 PM 3/23/00 , CORBIT GIBERSON wrote:
>Before I really get goin I think I should get myself a multimeter. But
>my experiance with electronics is nill ( in fact I think I'm pretty
>dense) and I don't know what to look for in a multi, any help would be
>greatly appreciated. I'd like something basic enough that I can jump
>right in, but not so basic that as I improve I don't have to replace
>it. Thanks all!

Y'know, the Rat-Shack stuff is pretty good for inexpensive, well-featured
meters. I've got/gone through 3? 4? (Not because of failures, just better
features)

Basic digital model is worth about $30. The really good ones are about
$100-$140 (Canadian), and cheaper if you wait for a sale (which they are
GUARANTEED to be featured in on a monthly rotation, saving about 20%).

If you think you'll be into electronics a while, spend the extra $70 and
get a meter with more features than you think you'll need. As you get more
knowledge, you'll be able to better use it.

I suggest either the 22-174 (auto-ranging, cap test, diode test, nifty
transistor test) or the 22-168A (manual-ranging, cap test, basic transistor
test, frequency, logic, and data interface to PC).

Regards,
Dave
---------------------------------------------------------------
"Um, no - that's H,R,Y,N,K,I,W. No, not K,I,U,U, K,I,_W_. Yes,
that's right. Yes, I know it looks like "HOCKYRINK." Yup, only
2 vowels. Pronounciation? _SMITH_".
http://www.solarbotics.com



12429 Thu, 23 Mar 2000 23:53:41 -0700 [alt-beam] Re: Dumb newbie Q. "Hyndman" [snip]
>hey we newbys gotta start sometime
>fluke is a good name brand but $$$
[snip]
Fluke is a good brand, but unless your planning on using your DMM on your
roof checking solar cells, just happen to fall off and want your DMM to be
unscratched....
Devin



12430 Fri, 24 Mar 2000 17:52:18 +1100 [alt-beam] Re: Logic puzzle - I need to built a new gate... :-) beam@sgiblab.sgi.com "Ben Hitchcock"
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content-transfer-encoding: 7bit

Sorry about that, I just had to crow a little bit :-)

I was sure that you wouldn't let a clanger like that go uncorrected so I had
to quickly hit the reply button before you fixed it up. In my haste I made
an equal mistake, so my previous circuit won't work. Here's my corrected
version. It's interesting that a problem like this one can generate so many
different solutions!

I get the logic to be output 1 is S2 OR(NOT S1). Output 2 = 0 of course :)
Using some convolution you get (NOT S2) AND (S1), which rearranged gives
your logic!


Ben

----------
>From: Wilf Rigter
>To: "'beam@sgiblab.sgi.com'"
>Subject: RE: Logic puzzle - I need to built a new gate... :-)
>Date: Fri, 24 Mar 2000 14:09
>

> In the space of a few minutes I read the puzzle, drew the schematic, posted
> it and hit the road and then it dawned on me that I had made a grapho (like
> a typo) in the drawing. I arrived home and sent the correction within 10
> minutes of my original post but strangely it never arrived on the list. So
> here again is the corrected drawing still only 3 components (sorry Ben):
>
> <>
> BTW the logic is OUTPUT1 = S1 AND NOT S2 and OUTPUT2 = 0
>
> enjoy
>
> wilf
>
>
>
>> -----Original Message-----
>> From: Ben Hitchcock [SMTP:beh01@uow.edu.au]
>> Sent: Thursday, March 23, 2000 5:39 PM
>> To: beam@sgiblab.sgi.com
>> Subject: Re: Logic puzzle - I need to built a new gate... :-)
>>
>> My initial thoughts on this were: Wilf beat me to the best solution again.
>> So I plodded through all the possible states, and I think that maybe
>> Wilf's circuit might need some modifications...
>>
>> Let's consider the case of both switches closed. Justin said that when
>> both switches were closed, he wanted output 1 to be high.
>>
>> So to Wilf's diagram:
>> Switch 1 will allow current through to the 3904, turning it 'on'.
>> Switch 2 will ground the emitter, which because the transistor is on will
>> drag the output 1 down to ground.
>>
>> This results in a closed,closed = low output, which I think should be
>> closed,closed = high.
>>
>> In my circuit I neglected to mention that both switches should be
>> connected to Vcc.. details details.
>>
>> Have I out-designed the almighty Wilf? :-) *hoping but not believing*
>>
>> Ben
>>
>> > Three components are needed as shown below:
>> >
>> > enjoy
>> >
>> > wilf
>> >
>> > <>
>> > > -----Original Message-----
>> > > From: Justin [SMTP:JAF60@student.canterbury.ac.nz]
>> > > Sent: Thursday, March 23, 2000 2:04 PM
>> > > To: beam@corp.sgi.com
>> > > Subject: Logic puzzle - I need to built a new gate... :-)
>> > >
>> > > Hiya,
>> > > For the turning system of a walker I'm designing, I ran into an
>> engaging
>> > > logic problem that I thought I'd share will you (mainly in the hope
>> that
>> > > someone could solve it in a more elegant manner than I have :-).
>> > >
>> > > The problem: (As illustrated below) I have a 4-state truth table and
>> > > want to build a circuit to give these outputs at the appropriate
>> input.
>> > > It's easy if I use an XOR gate, but that would mean adding an entire
>> > > extra IC and I'll be trying to build small. My current solution when
>> > > freeformed would be slightly smaller than a chip, trouble is, it needs
>> > > adjusting when the voltage changes, and the voltage will change a lot
>> > > (solar walker) thus ruling out my design. I have no idea what the
>> > > circuit for an XOR gate is, and I think that could give someone who
>> does
>> > > a big advantage.
>> > > The outputs are connected to the enable pins of a HC240, so that's the
>> > > kind of HIGH/LOW requirements the outputs have to meet.
>> > >
>> > > If someone could see a way to fix the sensitivity of my circuit, that
>> > > would also be great :-)
>> > >
>> > > Here is the guff: << File: puzzle1.gif >>
>>
>> [Attachment, skipping...]
>>
>>
>> --
>> Nothing is foolproof to a sufficiently talented fool.
>


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Attachment: puzzle2.gif

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12431 Fri, 24 Mar 2000 18:21:18 +1100 Re: Nu/Nv smt boards "Richard Piotter"
> Sounds cool! Have you tracked down a source to purchase the single
> inverter chip (in quantities of course)?
>
> I think most people can solder capacitors and resistors on. Did you use
> the design with the two sockets, that lets you plug resistors and
> capacitors in? If so, great!
>
> Can you send an image of the layout over. I'm afraid to dig for my
> images! in my 1822 messages (that's just the inbox!!! :)
>
>
> Steve Jones wrote:
> >
> > Hi Richard,
> >
> > I am just double checking everything now. I should have them in my hands
in
> > about a week. The boards are un populated, but they are cool in the fact
> > that they are super thin I think only 1/16 or less thick. I will let you
now
> > more later. Obviously the more orders the cheaper thay are. Cheers for
now
> > Steve.
> > ----- Original Message -----
> > From: Richard Piotter
> > To:
> > Sent: Wednesday, March 22, 2000 7:04 PM
> > Subject: Re: Nu/Nv smt boards
> >
> > > Wow! That's cool! I'd consider 50-100 myself.
> > >
> > > Are they PCBs only, or are they fully populated boards?
> > >
> > > Sounds great. Have you verified the design with the actual pin outs of
> > > the chip? I'd hate to have made a mistake and someone copy it. I
beleive
> > > it's right, but it's always wise to double (or quadruple :) check
stuff.
> > >
> > > How long would it be till you recieved them, after you order?
> > >
> > > This is great! I look forward to seeing these boards become a reality!
> > >
> > >
> > > > Steve Jones wrote:
> > > >
> > > > Hello All,
> > > >
> > > > This is an old subject but I had need for a single inverter Nu/Nv
and
> > > > having seen Richard Poiters I made up the dip package on my
schematic
> > > > layout program the same as Richards. Any ways I am having 100 made
up
> > > > for myself at a cost of about $1.50 U.S. a piece and I thought I
would
> > > > send an offer out to the list to see if any one else would like some
> > > > at the same time. Please send your replies to me privately at
> > > > skylift@ora.auracom.com attention Steve Jones
> > >
> > > --
> > >
> > >
> > > 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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