38
The following diagrams demonstrate the differences between trigger, gate and FSK tone
switching for a list of 2 frequencies switched by a square wave (positive slope specified on
TRIGGER IN setup).
The maximum recommended tone frequencies and trigger/gate switching frequencies for the
three modes are as follows:
GATE:
Maximum tone frequency 50kHz; maximum switching frequency
<lowest tone frequency.
TRIGGER:
Maximum tone frequency 50kHz; maximum switching frequency 1MHz.
FSK:
Maximum tone frequency 1MHz; maximum switching frequency 1MHz.
Tone Switching Source
The signal which controls the frequency switching is that set by the
source
soft
−
key on the
TRIGGER IN
setup screen. The
slope
field on the same screen sets the active polarity of
that signal; when set to
positive
the rising edge of the trigger signal is active or the high
level of the gating signal is true and the reverse is true for a
negative
setting. The signal
that can be selected by the
source
soft
−
key can be the Internal Trigger Generator, an
external trigger input, the front panel MAN TRIG key, a remote command and, for mutli
−
channel
instruments, Trigger Out of an adjacent channel; a full explanation for each of these can be found
in the Triggered Burst and Gate chapter.
DTMF Testing with a Multi
−
Channel Generator
An important use of Tone mode is DTMF (Dual Tone Multiple Frequency) testing in which 2
channels are set up with equal length lists of different frequencies and are triggered from a
common signal. The outputs are summed together using the internal sum facility, see SUM
chapter. DTMF testing generally uses sinewaves in the frequency range 600Hz to 1.6kHz.
It is also possible to set up DTMF testing using two single channel instruments triggered by a
common external signal and summed using the external SUM capability.
Содержание TGA1240 Series
Страница 1: ...TGA1240 Series 40MHz Arbitrary Waveform Generators INSTRUCTION MANUAL ...
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