Fluke 271 manual Generating Swept Signals, TRIG/SWEEP OUT signal

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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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