Racal Instruments 3156B, Руководство пользователя

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3156B User Manual
Racal Instrument © 2005 WaveCAD 4-23
Run Mode
The Run Mode group provides access to the various trigger modes of
the modulation functions. Note that the run modes that are shown on
this panel behave differently than the Main Panel run mode. For
example, placing the 3156B in triggered FM, the instrument idles on
carrier frequency until triggered. None modulated functions do not
output any signal until triggered.
The burst parameter in this group programs the burst count for the
modulation functions. To change burst count value, point and click on
the burst parameter. The value that is associated with the lit LED is
displayed on the digital display. You can use the dial, keyboard, or the
[
↑
] [
↓
} keys to adjust the readout to the required setting. After you
modify the reading, press Execute to update the 3156B with the new
reading.
Note
Normal color of the digital reading is dark blue. If you
modify the reading, the color changes to a lighter shade of
blue, indicating that the 3156B has not been updated yet
with the new parameter. Pressing Execute will update the
instrument and will restore the color of the digital readout
to dark blue, indicating that the displayed value is the
same as the generator setting.
Also note that the digital readout has an autodetect
mechanism for the high and low limits. You cannot exceed
the limits if you are using the dial but only if you use the
keypad. In case you do, the program will not let you
download an illegal parameter and you’ll be requested to
correct your setting.
FM
The FM Group is divided to two sub groups: Standard FM and
Arbitrary FM. The difference between the two FM types is that with the
standard FM, one can select between built-in standard waveforms to
modulate the carrier. For arbitrary FM, the modulating waveforms are
designed in the FM composer and can take any arbitrary shape as
required by the application.
Press on Sine, Triangle, Ramp, or Square to modulate the carrier
waveform with one of the built-in waveforms. Press Arbitrary to allow
the FM composer generate custom waveforms to modulate your
carrier signal.