Fluke DDS Function Generator 271 - Manual (Page 26)

271
Getting Started Manual
instrument's AUX OUT socket in order to see the phase
effects more clearly.
There are some limitations on using the phase control at
frequencies above 30 kHz - chapter 5 of the Users Manual
explains these in detail.
Generating Swept Signals
The instrument has an independently-controlled internal
trigger generator which produces a square wave with a
period from 20 µs to 200 s (in 20 µs steps), corresponding
to a repetition frequency from 0.005 Hz to 50 kHz. In most
modes the signal is made available at the rear panel
TRIG/SWEEP OUT
socket.
In sweep mode, the sweep begins on the negative edge of
the signal (the transition from +4 to 0 V; if you include
markers in the sweep set-up then each marker produces
an additional narrow +1 V pulse on the
TRIG/SWEEP OUT
signal.
For this tutorial we will generate a logarithmic sine wave
sweep from 261.6 to 1108.7 Hz. This 2-octave range is
well within the limits of audibility, so you can listen on
headphones if you wish. Set the amplitude to about -
10 dBm or you may be surprised by the intensity.
The description "logarithmic" means that the sweep
spends an equal period at each note of the scale (and is a
misnomer because the rate of frequency increase with
time is in fact exponential).
The set up process is as follows:
Press RECALL, 0, ENTER to reset to the factory defaults.
Then press EDIT and SWEEP.
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