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The percentages for CT, L and CA show what part of the coil and capacitor resource
was used for this frequency to achieve the tune. The resource is the maximum useful
inductance L and capacitance C depending on the frequency.
If CT is not zero, then CA is zero and the configuration of the matching network is “L”
(typical for low impedances at the antenna output).
If CA is not zero, then CT is zero and the configuration of the matching network is “re
-
verse L” (typical for high impedances at the antenna output).
In some cases, it may be that both CT and CA are zero (or a very low percentage on
one side). If the inductance is also a low percentage, then the load is with impedance
close to 50 Ohm.
This data may lead you to conclude:
-
What reserves you have left for compensating possible fluctuations in antenna
impedance as a result of external effects in the future, such as a change in weather
conditions, change in antenna environment, e.g. newly installed or removed antennas,
bulky conducting objects in antenna vicinity, etc.
-
If you record the data of the tuner resource used in the frequency bands for
your antennas, you can use their changes in the future to determine the stability of the
antenna impedance in time, thus you can prevent possible failures in an antenna or
feeder, and you can promptly take precautions to improve the reserve resource before
it is too late.
The ANTENNA or ANTENNA
buttons can be used to review the resource table
for another antenna in the same band.
The SEGMENT or SEGMENT
buttons are used to select (highlight) a different
frequency segment in the table. Simultaneously pressing the two
SEGMENT
but
-
tons for more than 1s selects the next BAND for review (the preceding band cannot be
selected).
Simultaneously pressing and holding for more than 2s the two
ANTENNA
buttons
deletes the shaded segment tuning, and “- - - -” is displayed in place of the hours.
6.4 MEASUREMENTS IN THE TUNER – ATU MEASURE MENU
This menu allows remote measurements of some RF values directly at the antenna
outputs of the tuner (without the transformation action of the matching circuit). This
data can be used to troubleshoot and diagnose the status of the antennas and feeders
(see S. 7.4).
Five values are measured for the current operating frequency segment and current
antenna output, as well as three general tuner values:
Summary of Contents for ACOM 04AT
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