Tektronix 2236, Инструкция по эксплуатации

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Operating Instructions— 2236 Service
the B SEC/DIV switch setting. The start of the B
Sweep is delayed from the start of the A Sweep by
a time determined by the settings of both the A
SEC/DIV switch and the B DELAY TIME POSI­
TION control. Gated frequency, period, width, and
totalize measurements are made on the B Trigger
signal.
0 2 ) POSITION Control — Horizontally positions both the A
Sweep and the B Sweep displays and horizontally po­
sitions X-axis in the X-Y mode.
(2 3 ) A/B SWP SEP Control — Vertically positions the B
Sweep trace with respect to the A Sweep trace when
ALT HORIZONTAL MODE is selected.
(2 4 ) B DELAY TIME POSITION Control— Selects the
amount of delay time between the start of the A
Sweep and the start of the B Sweep. In
A TIME
mode, the B DELAY TIME POSITION control oper­
ates in conjunction with the
A
TIME POSITION con­
trol. The B DELAY TIME POSITION control moves
both intensified zones (reference and comparisons),
while the
A
TIME POSITION control moves only one
intensified zone (time-measurement point). Time dif­
ference between the start of the two intensified zones
is displayed on the readout. In DLY TIME mode, only
one intensified zone is displayed which is controlled by
the B DELAY TIME POSITION control. The time dif­
ference between the start of the A Sweep and the
start of the intensified zone is displayed on the
readout.
TRIGGER
Refer to Figure 2-6 for location of items 25 through 34.
A TRIGGER Mode Switches — Three section switch
that determines the trigger mode for the A Sweep.
SGL SWP RESET — Press in the spring-return but­
ton momentarily to arm the A Sweep circuit or a
single-sweep display or to reset the CTM when in
TOTALIZE mode. In CH 1 V mode, pressing the
SGL SWP RESET button will enter or cancel rela­
tive reference mode.
In single-sweep display mode, the trigger system
operates the same as NORM, except only one
sweep is displayed for each trigger signal. Another
sweep cannot be displayed until the SGL SWP RE­
SET button is momentarily pressed in again to re­
set the A Sweep circuit. This mode is useful for
displaying and photographing either nonrepetitive
signals or signals that cause unstable conventional
displays (e.g., signals that vary in amplitude,
shape, or time). It also allows the gated totalize
function to acquire signals over just one gate inter­
val for events counting.
P-P AUTO-TV LINE — Permits triggering on wave­
forms having repetition rates of at least 20 Hz and
television lines. Sweep free-runs in the absence of
an adequate trigger signal or when the repetition
rate is below 20 Hz. The range of the A TRIGGER
LEVEL control is restricted to the peak-to-peak
range of the trigger signal.
NORM — Sweep is initiated when an adequate trig­
ger signal is applied. In the absence of a trigger
signal, no baseline trace will be present.
TV FIELD— Press in both P-P AUTO and NORM
buttons. Permits triggering on television field sig­
nals. A TRIGGER LEVEL control range and auto
baseline are the same as in P-P AUTO.
0 6 ) TRIG’D-READY Indicator — LED illuminates when ei-
ther P-P AUTO or NORM Trigger Mode is selected,
when the A Sweep has been triggered (TRIG’D).
When SGL SWP RESET button is momentarily
pressed in, the LED illuminates to indicate that the A
Trigger circuit is armed (READY) for a single sweep
display.
2 6