LDG AT-200PROII, Operation Manual

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PAGE 13
The default value of SWR threshold is 2.0:1. The following example shows setting the SWR
threshold to 1.7:1.
Antenna Selection: Press the Ant button momentarily to toggle which antenna port is
currently active. The
ANT 2
LED will light when Antenna 2 is selected, and is off when
Antenna 1 is selected. When toggling the antenna selection, the previous tuning settings for the
newly selected antenna are also recalled. This is useful when comparing antenna performance on
the same frequency.
Transmitting and Receiving
During receive operation, only the antenna and bypass indicator LEDs are lit on the AT-
200ProII. During transmit, the forward RF power level is displayed on the PWR bargraph, and
the SWR is displayed on the SWR bargraph.
When reading the SWR bargraph, an illuminated LED on the graph means “The SWR is at
least this much.” In other words, if the 1.3 LED is lit, it means that the SWR is between 1.3 and
1.5:1. No LEDs lit means the SWR is less than 1.1:1.
Bypass LED
The
Bypass
LED indicates that all of the inductive and capacitive tuning elements in the
tuner are in their zero state. That is, no series inductance is being applied, nor any capacitance in
parallel. You can quickly enter into bypass by pressing the
TUNE button momentarily. Pressing
the TUNE button momentarily again will return the tuner to its previous settings.
The Bypass LED lights any time that all tuning elements are zero. This can happen also if
you manually decrease the inductance and capacitance to zero using the front panel buttons, or if
a tuning operation results in the inductors and capacitors all being zero. The
Bypass LED may
even blip on momentarily during tuning, to indicate that the combination of inductors and
capacitors being tried at that instant is all zeros.
As soon as even a single tuning element is no longer zero, the Bypass LED extinguishes.