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Old June 5th 09, 04:52 AM posted to rec.radio.amateur.antenna
dykesc dykesc is offline
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First recorded activity by RadioBanter: Apr 2007
Posts: 53
Default Using Tuner to Determine Line Input Impedance

On Jun 4, 12:29*pm, "Jerry" wrote:

* I may be missing something. *But, if the objective it to learn if the
local 105 MHz signal is actually introducing error into your impedance
measurement, only a few Smith Chart Polts are needed. *You know the path (on
the Chart) the shunt reactance will have taken while being adjusted to make
a "match". * You also know the path the series reactance took. * Start from
the Chart center and move the impedance along the circles of constant
resistance for the series reactor. *Move along the circles of constant
admittance for the shunt reactance. * When the Xc and Xl are both known, and
you know which is closest to the "transmitter", it seems that a "program" is
unnecessary. *What am I mising?

* * * * * * * *Jerry * KD6JDJ


Thanks Jerry. No you aren't missing anything other than the fact that
my familiarity with Smith Chart analysis is limited to working through
a few exercises in the last chapter of the ARRL Antenna book. I will
be looking for more Smith Chart tutorial info on the web and am
certain I can get myself up to speed enough to start working with
conductance, suseptance, admittance, etc.

Thanks again. From your post it appears it will be a straight forward
exercise once I get my head around it.

73
Dykes AD5VS