Palstar ZM-30, Руководство пользователя

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allow you to prepare for a special scan and
they will be in effect when you exit from the
Band function.)
,
Pressing the SCAN pushbutton will
automatically sweep the antenna analyzer
test signal across the band range previously
selected, incrementing from the lower
frequency limit to the upper frequency limit,
in steps of 100 Hz, 1 kHz, 10 kHz, or 100
kHz, as preset in the Setup menu. The red
BUSY LED is turned on during the scan and
the following message is displayed:
~~Scanning~~
(please wait)
The reflectometer signals are sampled after
each step change and are used to compute
the SWR and complex impedance at each
frequency step. Each SWR value is
compared to previous value in order to
determine if a minima, or a “dip”, has
occurred at this point in the scan. If so, that
data point is stored for later display. The
Scan takes approximately 6 seconds at the 1
kHz step rate. At the end of the scan, the
Impedance mode is automatically entered
and the SWR and impedance data at the
frequency of resonance is displayed.
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Pressing the MODE pushbutton presents
sub-displays representing the four modes
available in the instrument: Impedance,
Capacitance, Inductance and VFO. To enter
a specific mode, press the dial pushbutton
when that mode name is displayed.
"7 $
This is the main operational mode for the
antenna analyzer. Impedance mode is
entered automatically during the power-on
sequence, and can be re-entered from any
other mode by pressing the dial pushbutton
when Impedance is displayed. Upon entry
to the Impedance mode, you will see the
following typical display:
SWR 10,345.00
2.1 49 + j 23
•
The top line indicates the frequency.
•
The first number on the second line is
the SWR. In this case it indicates 2.1:1
•
The middle value is Resistance, the real
part of Impedance. In this case it is 49
ohms.
•
The rightmost value is the Reactance, or
the reactive part of Impedance. In this
case it is 23-ohms inductance.
(Capacitive reactance would be indicated
as a negative number.)
2 ! 3 5
In the Impedance mode, you have the ability
to manually adjust the frequency and see the
SWR, resistance and reactance values at
whatever frequency is dialed up.
Frequency is changed by adjusting a single
digit indicated at the point in the display
where the cursor
( _ ) is. Upon power-up of the instrument,
the 10 kHz digit is the adjustment point, as
shown by the digit with the cursor in the
display above.
To move the cursor to a different digit to be
adjusted, press the dial pushbutton while
simultaneously turning the dial. The cursor
will move to any of the seven available
digits, allowing subsequent up/down
adjustment of that digit with the dial
pushbutton is released.
Rotating the dial clockwise will increase the
digit value and, correspondingly, the signal
generated by the unit. Counter-clockwise
rotation will decrease the digit and the
generated signal.
When the digit is incremented past 9, or
when it is decremented past 0, the digits
above the selected adjustment point are
rolled up or down, respectively.
Using this frequency adjustment scheme, the
user can conveniently pick an “increment”
digit and manually scan frequencies with the
desired granularity. Rough scans can