[ot] use of a long coaxial cable <OT>

[Rick Bowers]

At 1/22/2007 01:03 AM, you wrote:
>On Sun, 2007-01-21 at 22:16 -0600, Alma J Wetzker wrote:
> > Ric Moore wrote:
> > > On Sun, 2007-01-21 at 06:53 -0500, David Bandel wrote:
> > >> On 1/21/07, Ric Moore <wayward4now at gmail.com> wrote:
> > >>> On Sat, 2007-01-20 at 20:38 +0800, Man-wai CHANG wrote:
> > >>>>> 10base2 is 50 Ohm.. period.
> > >>>>> 75 Ohm is probably (cable) TV or radio.
> > >>>> Do we need special equipment to measure impedance? I have forgotten my
> > >>>> A-Level physics... :)
> > >>> Just an Ohm meter...
> > >>>
> > >>> E = I times R
> > >>> Energy = Impedence times Resistance  which translates to:
> > >>> Volts = Amperage times Ohms.
> > >>>
> > >>> I've always wondered why they changed all the words?? Who and When?
> > >>>
> > >> They may have changed some of the words at some point, but resistance
> > >> and impedance are not the same.  Resistance is static.  Impedance,
> > >> however, is not static, it changes depending on frequency.  You don't
> > >> just measure impedance with an ohm meter.  Consider yourself gonged.
> > >> Show's over for you.  Please leave the planet.  Resistance is futile.
> > >
> > > JEEEEZZZ! Dang me. You measure resistance (ohms) with an ohm meter and
> > > the impedance (amperage) with an ampprobe. Why they changed up the words
> > > is beyond me.
> > >
> > > Man-wai, the deal is when that Ohm's Law equation came out, they used
> > > the words Energy, Impedance and Resistance.  Now they are:
> > >     Voltage, Amperage and Ohms.
> > >
> > > Yet, Ohms law is still written as  E = I X R ...out of respect for the
> > > old geeze who figured it all out for us. You're supposed to be
> > > enlightened to the point of doing the conversion in your head. Thanks to
> > > Meester Senor Bandel of Panama for pointing out my faux paux. <smiles
> > > grimly> At least he'll be old and grey someday too... falling face first
> > > into his oatmeal. I get no small measure of satisfaction from that fact.
> > > <smirks> Ric
> >
> > True, you do measure resistance with an Ohm meter.
> >
> > You *cannot* measure impedance with an Ohm meter.  You need some special
> > equipment.  In lab, we did it with a frequency generator and and
> > oscilloscope.  VERY simply, Ohms work for DC and impedance is for
> > everything else.  Impedance is a function of frequency. [R(f)]
> >
> > In my current class, even Ohm's law is not fixed.  Thanks to a guy named
> > Maxwell.  The 'E' in Ohm's law stands for Electro-Motive Force, or EMF,
> > what we usually now call voltage.
> >
> > We need to stop this thread before one of my professor's sees it and
> > goes back to change my grade.  That would be bad, I am done in May.
>
>They call me Sparky, 220 440 880 is the voltage ranges I play with, not
>this little itty bitty etched stuff... oh hell nah, double ought. I eat
>nails and pass lightning.  Ohms work just fine in a series circuit.
>Covert the wattage rating (PIE) so I can get the ohms I expect to read
>in a coil and that works for me. The winding will be good, shorted or
>open. Nice and simple. I like my electronics to make really big sparks
>and blow the tip of my screwdriver off... "real good". Everyone else
>runs for cover.
>
>When I was in my 20's my soon-to-be "step-dad", the MASTER Electrician
>had strung 4 light sockets over head in a pole barn.
>"Rick-ah-ey" (ALabama) One of these sockets ain't workin'... can you
>check 'em?" Not volt meter anywhere in sight. Right, I'm seeing this
>picture. So, I walked along sticking two fingers into each one and got a
>jolt on #'s 1,2,4 with 3 being a no shocker. I just kept my finger in
>number 4 and calmly told him "...this must be it, nothing." I got the
>eyeball for several seconds and so Mr. MASTER Electrician comes up and
>sticks his finger in number 4, just like I planned. "YEOW!" I said,
>"Damn, I didn't get anything at all on that one." and looked all
>innocent. He said that he thought it was number 3. <sly grin> The juice
>has just never bothered me, not that I'm gonna jump into a substation
>with a running garden hose, a bag of rock salt and a trampoline. Nah...
>I'm not a MASTER Electrician either. 30 some years later, he still gives
>me this sideways look. Go figure. Ric
>
>
>Ric aka Sparky
>

Hee Hee! A man after my own heart.
I've got some customized tools as well. One of my favorites is an old 
pair of dikes that now serve equally well for stripping 14 guage 
wire. I burned a nice 14 ga hold in 'em when I cut the wrong wire.
It was kinda funny. I was up in the attic movin' some wires out of 
the way to put in a whole house fan. The dang contractor rn all the 
wires in the attic down the center of the hallway, right where I 
needed to install the fan. So I had to move a few. Thought I had 'em 
all turned off, but missed one.
So, I'm in the attic, cut the wire, and POW! Burned a 14ga groove in 
the dikes.
I'm a bit stunned for a second, and the wife yells from the living 
room "Hey, the TV just went off" LOL!!

I usually don't bother trying to find which danged circuit breaker 
controls the circuit I need to work on. I change plugs and switches 
"live". And if I need to cut power, I just short out the circuit I 
need off. It tells me real quickly which breaker it is. ;-)

'Been working with 'lectricity nearly all my life. Not a MASTER 
electrician either. Or even licensed. It's more fun this way.

~Rick


>================================================
>My father, Victor Moore (Vic) used to say:
>"There are two Great Sins in the world...
>..the Sin of Ignorance, and the Sin of Stupidity.
>Only the former may be overcome." R.I.P. Dad.
>Linux user# 44256 Sign up at: http://counter.li.org/
>http://www.sourceforge.net/projects/oar
>http://www.wayward4now.net
>================================================
>
>
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