Waveform Amplitude; Continuous Mode; External Reference; 3.1 4.4 Waveform Offset - Wavetek 75 Instruction Manual

3.1 4.2 External Reference
An external "clock" signal can be used as the main
"sample frequency" by pressing the REF soft key(from
the Parameter menu) and using the Control knob to
select "REF EXTERNAL". The external clock signal is
connected to the "Ref In'' connector on the rear panel.
3.1 4.3 Waveform Amplitude
The waveform "amplitude" is displayed in volts peak.
This amplitude is measured from the center of the
waveform window (Y
=
0) to the top or bottom of the
waveform window (Y
=
+
2047). To set the amplitude,
press the AMPL soft key (from the Parameter menu) and
turn the Control knob as required. If the waveform does
not reach the top or the bottom of the window the
indicated amplitude will not be [he actual amplitude of
the output. The Normalize editing feature can be used
to scale the waveform to match the amplitude setting.
Move the thumbtacks to each end of the waveform and
press the "NORML" soft key (from the Edit menu). The
sum of the amplitude and offset settings automatically
determines the best output attenuator range and
therefore the offset setting will affect the resolution of
the amplitude setting. The sum of the amplitude setting
and the absolute value of the offset setting cannot
exceed 5.2V.
3.1 4.4 Waveform Offset
The waveform "offset" is the voltage from zero to the
center of the waveform window (Y
=
0). To set the
waveform offset, press the OFFSET soft key (from the
Parameter menu) and use the Control knob to set the
desired value. The sum of the amplitude and offset
settings automatically determines the best output
attenuator range and therefore the amplitude setting will
affect the resolutionof theoffset setting.Thesum of the
amplitude setting and the absolute value of the offset
setting cannot exceed 5.2V.
3.1 5 OPERATIONAL MODES
The Model 75 can operate in any one of five different
modes. These are Continuous, Triggered, Gated,
Toggled, or Burst. Adescription of each of these modes
isgiven in paragraphs 3.1 5.1 thru 3.15.5.Tochange the
operational mode, press the MODE soft key (from the
Parameter menu)and use thecontrol knob to select the
desired mode.
All of the modes except Continuous use a trigger to start
the waveform output. The trigger cancome from theTrig-
ger key on the front panel, from the "Trig In" BNC con-
nector on the front panel,or via the optional GPlB or
RS-232C interface. The polarity(s1ope) that causes the
waveform to run can be set to either positive of negative
by pressing the TRSLP soft key (from the Parameter
menu) and turning the Control knob. When the trigger
slope is set to positive, pressing the Trigger key or
inputting a rising edge on the "Trig In'' BNC will start the
waveform. When the trigger slope is set to negative,
releasing the Trigger key or inputting a falling edge on
the "Trig In" BNC will start the waveform. If the "Trig
In" BNC is held high, the polarity of the Trigger key will
be reversed.
In all modes except Continuous, the waveform will stop
and wait for another trigger only at the break points. By
default, one break point is set at the beginning of the
waveform. Break points can be set anywhere in the
waveform or the default break point can be removed if
desired. Setting and clearing break points will be dis-
cussed later.
NOTE
Ifallof the breakpointsare removedfrom the
waveform, then all of the modes will act like
the Continuous mode.
3.1 5.1 Continuous Mode
In Continuous mode, the output runs repeatedly from the
start address to the stop address. Neither the Trigger
key or the "Trig In'' BNCwill have any effect in this mode.
3.1 5.2 Triggered Mode
In the Triggered mode, the waveform stops at a break-
point and waits for a trigger from either the Trigger key
or the "Trig In" input. When a trigger is received, the
waveform runs until another break point is encountered,
then stops and waits for another trigger. With only the
default break point in the waveform, each trigger
produces one waveform cycle.
3.1 5.3 Gated Mode
I n the Gated mode, the waveform stops at a break point
and waitsfor a trigger signal. When a trigger is received,
the waveform runs until the trigger signal is removed and
then stops at the next break point. If the trigger slope
is set to negative, the waveform will start when the Trig-
ger key is released or the "Trig In'' input sees a high to
low transition and runs until the Trigger key is pressed
or the "Trig In" input goes high.
3.1 5.4 Toggled Mode
In the Toggled mode, the waveform stops at a break point
and waits for a trigger signal. When a trigger is received,
thewaveform runs until asecond trigger is received, then
stops at the next break point. In this way, each trigger
toggles the waveform "on" or "off".
Scans by ArtekMedia O 2006