Racal Instruments 3156B, Руководство пользователя

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3156B User Manual
Using the Instrument 3-32 Racal Instrument © 2005
4 – selects Sweep. Depending on the modulation run mode, the
output idles on carrier frequency until a valid enable signal is
applied to the generator. The following Sweep parameters are
available for modification: Start and Stop frequency range, Sweep
type and direction, Sweep time and marker frequency. The Sweep
function calls are described in Chapter 4.
5 – selects Frequency hops. Depending on the modulation run mode,
the output idles on last hop frequency until a valid enable signal is
applied to the generator then the frequency hops from frequency
to frequency at a rate determined by the baud rate and sequenced
in the hop table. The following Frequency hops parameters are
available for modification: Hop mode, dwell time and marker
position. Hop table is programmable as well. The Frequency hops
function calls are described in Chapter 4.
Hints
1) The carrier waveform in modulation is always
sinewave
2) Modulation run modes are separate and different than
the non-modulated run modes
3) An operate enable command initiates modulation
however, once the output on command is used,
carrier is immediately available at the output
4) Following completion of trig or burst cycles, the
output resumes carrier frequency
As was hinted above, the modulation run modes are different than the
run modes for the non-modulated waveforms. The difference is in the
way the output generates the modulated waveforms. Use the following
function call to program the modulation run mode:
ri3156B_set_modulation_run_mode ()
The following options are available as modulation run modes:
Continuous – sine waveform idles on carrier frequency, modulation
starts after an enable command and continues
indefinitely till terminated
Triggered – sine waveform idles on carrier frequency. Each trigger
generates a single modulation cycle. The trigger
source is selected using the
ri3156B_set_trigger_source() function