Alt-BEAM Archive
Message #09844
To: beam@sgiblab.sgi.com
From: Blumojo13@aol.com
Date: Sun, 6 Feb 2000 16:17:32 EST
Subject: [alt-beam] CAPACITORS
http://leonardo.eeug.caltech.edu/~ee14/capacitor_guide.html
TRY HERE.
BLUMOJO13
9845 Sun, 6 Feb 2000 13:49:47 -0800 (PST) [alt-beam] Re: Capacitor Identification beam@sgiblab.sgi.com "Leonardo Boulton F." The easyest is to get a multimeter that meassures capacitance.
The way to get it from calculations is a bit harder, you need an
oscilloscope. I could tell you the eq. (I = C*dV/dt), but i sincearlly
don't know how to do it with an old RCT oscilloscope.
I recomend you get the multimeter...
--- David Stafford wrote:
>
> I've been dismantling some electronic junk for the parts.
> I have a bunch of caps but I don't know the values. Is
> there an easy way to check?
>
> I know I could look at the amount of time it takes to
> charge to a given voltage on a Scope. Then do some fancy
> calculations to determine the farad value. But I don't
> remember the equations (please tell me the equation to save
> me the effort if you happen to have it handy), and I don't
> have easy access to a scope. Any other suggestions?
>
> Also if anyone knows how to decipher the capacitor markings
> that would help me tremendously.
>
> Thanks
> Dave
> __________________________________________________
> Do You Yahoo!?
> Talk to your friends online with Yahoo! Messenger.
> http://im.yahoo.com
>
=====
I'm here... http://geocities.com/l.boulton
__________________________________________________
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Talk to your friends online with Yahoo! Messenger.
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9846 Sun, 6 Feb 2000 15:12:59 -0800 (PST) [alt-beam] Re: Capacitor Identification beam@sgiblab.sgi.com David Stafford Thanks,
I'll go shopping, and price out the meter.
Dave
--- "Leonardo Boulton F." wrote:
> The easyest is to get a multimeter that meassures
> capacitance.
> The way to get it from calculations is a bit harder, you
> need an
> oscilloscope. I could tell you the eq. (I = C*dV/dt), but
> i sincearlly
> don't know how to do it with an old RCT oscilloscope.
> I recomend you get the multimeter...
>
>
> --- David Stafford wrote:
> >
> > I've been dismantling some electronic junk for the
> parts.
> > I have a bunch of caps but I don't know the values. Is
> > there an easy way to check?
> >
> > I know I could look at the amount of time it takes to
> > charge to a given voltage on a Scope. Then do some
> fancy
> > calculations to determine the farad value. But I don't
> > remember the equations (please tell me the equation to
> save
> > me the effort if you happen to have it handy), and I
> don't
> > have easy access to a scope. Any other suggestions?
> >
> > Also if anyone knows how to decipher the capacitor
> markings
> > that would help me tremendously.
> >
> > Thanks
> > Dave
> > __________________________________________________
> > Do You Yahoo!?
> > Talk to your friends online with Yahoo! Messenger.
> > http://im.yahoo.com
> >
>
> =====
> I'm here... http://geocities.com/l.boulton
> __________________________________________________
> Do You Yahoo!?
> Talk to your friends online with Yahoo! Messenger.
> http://im.yahoo.com
>
__________________________________________________
Do You Yahoo!?
Talk to your friends online with Yahoo! Messenger.
http://im.yahoo.com
9847 Sun, 6 Feb 2000 19:25:55 EST [alt-beam] Re:Capacitor Identification-->Tutorial on reading caps beam@sgiblab.sgi.com CIRCITZ@aol.com ok, for reading caps that don't have any markings, you'll need a capacitance
meter, which I believe is becoming quite common on multi-meters now & days.
But for caps that have any markings it's pretty easy to do. Electrolytic
caps (tubular cases) have thier values along with thier tolerances written
right on the side. For disk type capacitors it's a little more difficult(but
not too hard, so don't give up on me just yet). Many caps of this type do
not define the unit of capacitance; in this situation locate a decimal point,
if there is a decimal point the true value is that number in microfarads
(uF), however if no decimal point exists the value is in picofarads (pF) and
needs to be analyzed a little more. If there is no decimal place and 3
digits are expressed and the last digit is a zero that is the true value in
pF. If the third digit is a number between 1 & 9, that is the multiplier
number and is the number of zeros that needs to be added to the pF value of
the cap. I'll give some examples@the end of the letter. NOW, any letters on
the end of the disk caps is for tolerances, and those values are as follows:
F = +/- 1%
g = +/- 2%
j = +/- 5%
K = +/- 10%
M = +/- 20%
Z = -20% + 80% <---never seen any of these though
470 <---470pF
473 <---47,000pF (47 nF)
475 <---4,700,000 (4.7 uF)
476 <---47,000,000pF (47 uF)
HOpefully that clears it up pretty well, if you need any clarification on
this, just post it to the group
9848 Sun, 06 Feb 2000 16:47:03 PST [alt-beam] A cool locomotion idea. alt-beam@egroups.com "Jonathan Smolders" Hi,
I was doing biology in school and I got to the part about bacteria. As I
was reading how the bacteria get around I thought that this form of
transportation might be able to be used in a beam robot. If you are not
familiar with how bacteria move around then I will try and summarize it for
you.
Here it goes (this was half copied from my text book):
Locomotion is accomplished with the flagellum. It is composed of three
parts: the filament, the hook, and the basal body. The filament (which is
all you see in the very crude picture I drew) attaches to the hook, a small
tube shaped like an "L". The hook slides onto a rod that sticks through the
cell wall. This rod, and all of the structures that attach it to the cell
wall make up the basal body. The rod and the hook fit together so smoothly
that the hook can actually spin around the rod in circles. When the
bacterium wants to move, a series of amazingly complex chemical reactions
make the hook spin. Since the filament is attached to the hook, it begins to
spin as well. The design of this marvelous structure looks remarkably
similar to the design of a jet engine.
Now you might think that the filament acts like a propeller and pushes a
bacterium around. That wouldn't work well because the filament is very light
weight. As a result, it does not make a great propeller.
However, when the flagellum spins in one direction, the rest of the cell
spins in the other direction! When I take physics, it said I would learn
that this is a consequence of the Law of Angular Momentum Conservation. The
cell then becomes it's own propeller.
Does anybody see the potential of a very cool mode of locomotion in Beam
robots? Although I haven't researched/thought about it much myself, it seems
like it would be relatively easy to build. Anyway just thought I'd share the
idea. If anybody want's to look more into this then I'd suggest picking up a
biology or physics book and start researching. What does everybody think
about this?
c ya,
Jonathan Smolders
beamrobotics@hotmail.com
p.s. I attached a very crude diagram of a bacterium with a flagellum.
______________________________________________________
9849 Sun, 06 Feb 2000 16:56:13 PST [alt-beam] Re: A cool locomotion idea. alt-beam@egroups.com "Jonathan Smolders"
format="flowed"
Sorry, I forgot to attach the diagram on the last message so here it is.
Jonathan Smolders
beamrobotics@hotmail.com
>From: "Jonathan Smolders"
>Reply-To: alt-beam@egroups.com
>To: alt-beam@egroups.com
>Subject: [alt-beam] A cool locomotion idea.
>Date: Sun, 06 Feb 2000 16:47:03 PST
>
>Hi,
> I was doing biology in school and I got to the part about bacteria. As I
>was reading how the bacteria get around I thought that this form of
>transportation might be able to be used in a beam robot. If you are not
>familiar with how bacteria move around then I will try and summarize it for
>you.
>Here it goes (this was half copied from my text book):
>
> Locomotion is accomplished with the flagellum. It is composed of three
>parts: the filament, the hook, and the basal body. The filament (which is
>all you see in the very crude picture I drew) attaches to the hook, a small
>tube shaped like an "L". The hook slides onto a rod that sticks through the
>cell wall. This rod, and all of the structures that attach it to the cell
>wall make up the basal body. The rod and the hook fit together so smoothly
>that the hook can actually spin around the rod in circles. When the
>bacterium wants to move, a series of amazingly complex chemical reactions
>make the hook spin. Since the filament is attached to the hook, it begins
>to
>spin as well. The design of this marvelous structure looks remarkably
>similar to the design of a jet engine.
>
> Now you might think that the filament acts like a propeller and pushes
>a
>bacterium around. That wouldn't work well because the filament is very
>light
>weight. As a result, it does not make a great propeller.
>
> However, when the flagellum spins in one direction, the rest of the
>cell
>spins in the other direction! When I take physics, it said I would learn
>that this is a consequence of the Law of Angular Momentum Conservation. The
>cell then becomes it's own propeller.
>
>
> Does anybody see the potential of a very cool mode of locomotion in
>Beam
>robots? Although I haven't researched/thought about it much myself, it
>seems
>like it would be relatively easy to build. Anyway just thought I'd share
>the
>idea. If anybody want's to look more into this then I'd suggest picking up
>a
>biology or physics book and start researching. What does everybody think
>about this?
>
>c ya,
>Jonathan Smolders
>beamrobotics@hotmail.com
>
>p.s. I attached a very crude diagram of a bacterium with a flagellum.
>
>
>
>
>
>______________________________________________________
>
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Attachment: Bacterium.jpg
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