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Old March 10th 06, 05:41 AM posted to rec.radio.amateur.antenna
Wes Stewart
 
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Default Current through coils

On Fri, 10 Mar 2006 04:23:03 GMT, Cecil Moore wrote:

Jerry Martes wrote:
I have a HP8405A Vector Voltmeter I'll give you and even pay the shipping
if that is of any help with the measurements.


Wow, thanks for the offer. That would certainly be more
accurate than eyeballing an o'scope. Do you think the
use of such would prove me right or wrong? Does the
VV compare two signals and report the phase difference?
Are the probes differential or coaxial? I've never used


The VVM probes are comprised of a quad diode sampling bridge followed
by an FET amplifier. They are nominally coaxial, although without the
BNC adapters, they have an exposed pin (very delicate) and at lower
frequencies they can be used much as a high impedance scope probe is
used.

The instrument uses a phase-locked oscillator to drive the samplers
with the "A" probe being the reference. One meter can be switched to
display the amplitude of either channel and the second meter reads the
phase difference between them.