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[TowerTalk] coax attentuation

To: <towertalk@contesting.com>
Subject: [TowerTalk] coax attentuation
From: n8de@thepoint.net (Don Havlicek)
Date: Tue, 08 Jan 2002 19:33:57 -0500
Al,
Wrote you direct, but thought I should put it on the reflector, too.
Take the resistor OFF at the 'source' end.  You have it in parallel with
the LOAD.  Then take those measurements again!
Don
N8DE

Mike & Coreen Smith wrote:
> 
> Wanna sell some of that coax?
> ;-)
> 
> Michael, Coreen & Corey Smith
> (VE9AA,  VE9AAA & Baby-VE9)
> 271 Smith Rd
> Waterville, NB
> E2V 3V6
> Canada
> http://members.tripod.com/~ve9aa/index.html
> http://www.geocities.com/RainForest/Vines/2174/
> 
> ----- Original Message -----
> From: Al Williams <alwilliams@olywa.net>
> To: <towertalk@contesting.com>
> Sent: Tuesday, January 08, 2002 5:50 AM
> Subject: [TowerTalk] coax attentuation
> 
> >
> >
> > ----- Original Message -----
> > From: "Al Williams" <alwilliams@olywa.net>
> > To: <Topband@contesting.com>
> > Sent: Monday, January 07, 2002 11:21 PM
> > Subject: coax loss
> >
> >
> >  I have been trying to determine signal loss in coax by using a dual trace
> > oscilloscope (Tek 465) connected to the input and output of the coax.
> > However, instead of a loss I
> >  am observing a gain!
> >
> >    My setup is using a MFJ-249 SWR Analyzer as the source and a BNC 51 ohm
> >  resistor connected to the source.  The opposite end of the coax is
> > connected
> >  to the scope and a 51 ohm carbon resistor with short leads.  Both
> resistors
> >  measure low swr (<l.2) with the MFJ.
> >
> >  The waveforms on input and output of the coax appear undistorted
> sinewaves
> >  but the output is greater than the input for frequencies up to about 30
> > mhz. The output
> >  increases as the coax length increases being about 20% greater with 130'
> of
> > LM400.  The MFJ
> >  measures SWR of about 2:1 (note; the two 50 ohm resistors at input and
> > output are in
> >  parallel.
> >
> >  Has anyone used this method?  What might be wrong with my setup?
> >
> >  k7puc
> >
> >
> >
> > ________________________________________________________________________
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> 
> ________________________________________________________________________
> This list is sponsored by the new eHam.net Store.  When you buy products
> like ICE filters, Array Solutions StackMatch, or M-Squared Antennas from
> the eHam Store for the same price you pay direct, a portion of the sale
> price goes to support this list.  Check it out at http://www.eham.net.
> 
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________________________________________________________________________
This list is sponsored by the new eHam.net Store.  When you buy products
like ICE filters, Array Solutions StackMatch, or M-Squared Antennas from
the eHam Store for the same price you pay direct, a portion of the sale
price goes to support this list.  Check it out at http://www.eham.net.

-----
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