Or to put it simply, the VNA contains a highly specialized radio receiver.
On Tue, 1 Apr 2025 23:03:04 +0000
"W0LEV via groups.io" <davearea51a@...> wrote:
If you have a close-by strong source of RF energy like FM or AM
broadcasters, police, ambulance, CB'ers, hams, ....... any of those and
more could be affecting the readings. This is not all that uncommon in
cities when the VNA is connected to a large antenna.
Dave - W?LEV
On Tue, Apr 1, 2025 at 7:51?PM kellogs via groups.io <mihai0226=
[email protected]> wrote:
Is it normal for the readings to fluctuate as much as 2-3 ohms ? As in
11+/-1.5 - j(70+/-1.5)
Dipole NMHA (antenna), balun, calibrated, two ferrites: one at the balun
and one at the VNA S11 port. No body / coax inadvertent movements,
everything taped down near the antenna.
Thanks
--
73
-Jim
NU0C
Jim Shorney