----- Original Message -----
From: "PY3CRX PY2PLL" <[email protected]>
To: "LF Group" <[email protected]>
Sent: Thursday, February 08, 2001 2:49 AM
Subject: LF: SWR X phase X reactive components
I need a help:
I have an SWR bridge - 2 X 1:40 transformers on a conventional circuit and
from this bridge I have two rectified voltages: forward and reflected.
On the other side, if I have any reactive component at load side, there
will
be difference between source signal phase and load signal phase.
Using a DBM I'm able to convert this phase difference into voltage.
The question is: how can I convert degrees in reactive component value? My
phase measurement ranges from -180 to +180 degree on a linear basis, e.g
the
phase comparator delivers some mV proportional to degrees.
Knowing this I'll be able to measure SWR, R and J at the same time.
Thanks in advance for any help ...
73
Marcus
PY3CRX/PY2PLL
S. B. do Campo - GG66rf
http://py.qsl.br
Active from "DC" to 24GHz
Marcus,
You are venturing into the "operating impedance bridge" (OIB) idea. An
article with some information is "Building an Operating Impedance Bridge" in
QST, Nov 1979, pp 11-17. I gather that the OIB can work while the
transmitter is in normal service, and R and jX can be read from calibrated
knobs on pots on the secondary side, after a null is found by adjustment.
73, Bob ZL2CA
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