Palstar ZM-30, Руководство пользователя

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manually be done by positioning the cursor
under the 100 kHz digit or the 1 MHz digit,
giving a wide and course scan of the
frequencies with a quick twist of the dial.
The signal frequency can then be set to the
area of interest and the cursor set to a lower
granular digit (e.g., 10 kHz or 1 kHz) in
order to manually perform a detailed scan
while watching displayed results for SWR,
impedance and reactance.
An
audio tone may be configured to sound
when turning the dial in Impedance mode.
When you approach a resonance (i.e., an
SWR "dip"), the tone lowers according to
the SWR. Thus the operator will have an
audible indication of when minimum SWR
is found. The tones may be enabled or
disabled in the Setup menu, and the setting
is saved in nonvolatile EEPROM so the
selection stays in the unit when power is
turned off.
NOTE: The practical lower limit of the ZM-
30 is about 400 kHz due to the coupling
capacitors used in the internal circuitry.
Signal levels will drop to an unusable level
with frequency settings below this level, so
the instrument prohibits adjustment lower
than this frequency. The upper limit of the
instrument is restricted to 30 MHz, as this is
the highest quality signal safely obtainable
from a DDS clocked at 100 MHz.
7 $
Capacitance mode may be entered at any
time by pressing the dial pushbutton when
Capacitance is displayed. Upon entry to the
Capacitance mode, you will see the
following typical display for about ½
second:
Capacitance (pF)
Then, the capacitance display screen is
shown, as illustrated below when a 120 pF
capacitor is connected to the RF output jack.
10,000.00
C = 126.4 pF
The top line indicates the frequency.
The second line is the computed value for
the load connected to the output jack.
Capacitance values that may be displayed
must fall within the measurement range of
the instrument. Keeping in mind the 1K-
ohm maximum impedance specification for
the analyzer, the display will only indicate a
numeric value for the capacitance when its
reactance is less than that 1K-ohm spec.
The equation used to compute the
capacitance is:
XC = 1/ (2 * pi * F * C)
When the frequency and/or capacitance is
beyond the instrument’s capabilities,
producing a value for XC greater than 1,000
ohms, the display will indicate as shown
below.
10,000.00
C = (Z>1K)
$
Inductance mode may be entered at any time
by pressing the dial pushbutton when
Inductance is displayed. Upon entry to the
Inductance mode, you will see the following
typical display for about ½ second:
Inductance (uH)
Then, the inductance display screen is
shown, as illustrated below when a 2.2 uH
capacitor is connected to the RF output jack.
10,000.00
L = 2.2 uH
The top line indicates the frequency
The second line is the computed value for
the load connected to the output jack.
Inductance values that may be displayed
must fall within the measurement range of
the instrument. Keeping in mind the 1,000-
ohm maximum resistance or reactance
specification for the antenna analyzer, the
display will only indicate a numeric value
for the inductance when its reactance is less
than that 1,000-ohm spec. The equation