5.Panel Operation
35
source.
(5)
If you select
Internal
, the modulating wave is set as a Square with 50% duty
cycle.
Press
the
FSK Rate
softkey to set the FSK rate. The rate at which the
output frequency shifts between the carrier frequency and the hop frequency is
determined by FSK rate (for internal source only). The range is 2 mHz – 1 MHz.
If you select
External
, use the
Mod/FSK/Trig
connector at the rear panel to
input the external modulating signal. Press the
Slope
softkey to switch between
Positive
and
Negative
polarity of the modulating wave to control the output
frequency. Set the slope to
Positive
, the generator would output the carrier
frequency when the external input signal is logic low level, and output the hop
frequency when the external input signal is logic high level. The situation is the
opposite when the slope is set to
Negative
.
(6)
Set hop frequency
:
Press the
Hop Frequency
softkey to set the hop frequency. The carrier wave
frequency shifts to the hop frequency with the specified FSK rate, and then
returns to the original frequency.
PSK (Phase Shift Keying)
Phase Shift Keying modulation is a modulation technique that shifts the output
signal phase between two phases: the carrier phase and modulating phase. Carrier
wave phase shifts to the modulating phase with the specified PSK rate, and then
returns to the original phase. The PSK user interface is shown below.
Figure 5-18: PSK user interface
