Tektronix PFG 5105, Инструкция по эксплуатации

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Operating Instructions
USING THE SWEEP GENERATOR
The PFG 5105/5505 also provides a sweep generator
function that outputs the selected sweep waveform
at the SWEEP OUT connector. Sweep type is linear.
The sweep time is controlled by the RATE setting;
sweep width is controlled by the START and STOP
frequency settings. The PFG 5105/5505 calculates the
waveshape with a 256-point length, between the
current START and STOP frequencies. The 256-point
waveshape constitutes one sweep cycle; each point
of the 256 points in the cycle's waveshape is output
at the rate set by the RATE function.
For example, a linear sweep with a START frequency
of 1
o
kHz, a STOP frequency of 11 kHz, and a RATE
of 3.9 millisecond will generate a linear sweep between
1
o
and 11 kHz with a cycle of 1 second.
The START and STOP frequencies must be in the
same sweep range; refer to sweep specifications in
Section 1 for ranges. If START and STOP frequencies
are not in the same sweep range, an error (261) is
generated. Valid START/STOP ranges are shown in
Table 2-8.
EXAMPLE:
If the stop frequency is set to 1.2 MHz, the frequency
range will be set from 120.1 kHz to 1.20 MHz. This
allows you to set the start frequency to a minimum
of 1 kHz, a 1200: 1 ratio.
However, if the stop frequency is set to 1.21 kHz,
the frequency range will be set to 1.21 to 12 MHz.
This changes the minimum start frequency to 1 O
kHz, only a 121: 1 ratio. This must be taken into
account when figuring sweep frequencies.
To turn sweep on, set the START and STOP frequen­
cies, then press RUN.
To turn off the sweep generator, press RUN again.
Table 2-9 lists the items that must be set to generate
a sweep.
Table 2-8
VALID START/STOP RANGES
Stop Frequency Range Sweep Frequency Range
1.21 MHz - 12 MHz 10 kHz - 12 MHz
120.1 kHz - 1.2 MHz 1 kHz - 1.2 MHz
12.1 kHz - 120 kHz 100 Hz - 120 kHz
1.21 kHz - 12 kHz 10 Hz - 12 kHz
120.1 Hz - 1.2 kHz 1 Hz - 1.2 kHz
12.1 Hz - 120 Hz 0.1 Hz - 120 Hz
0.012 Hz - 12 Hz 0.012 Hz - 12 Hz
Table 2-9
Purpose
Select sweep starting
frequency:
Select sweep
stopping frequency:
Select sweep rate:
Select SWEEP mode:
2-18
Step 1
START
STOP
RATE
RUN
USING THE SWEEP GENERATOR
Step 2
Enter frequency at which sweep will start (DATA
numeric, units keys), press ENTER.
See table and example above for sweep start and
stop frequency ratios.
Enter frequency at which sweep will stop (DATA
numeric, units keys), press ENTER.
Input rate value (DATA numeric, units keys); press
ENTER
(RUN toggles the sweep on and off.)
PFG 5105/5505 Instruction Manual