Tektronix 310A, Instruction Manual, Page: 12 / 132

Operating Instructions-Type 310A
Trigger
TRIGGER
Trigger Coupling-
Mode (AUTO AC
DC)
TRIG LEVEL
STA BILITY
PRESET ADJUST
Selects the source and slope of the
trigger signal which starts the sweep.
The sweep can be triggered from either
the positive-going or negative-going
portion o f the trigger signal in each of
the follow ing source positions;
+ EXT —: Trigger signal obtained
from an external signal applied to
the EXT TRIG INPUT binding
post.
+ I N T T r i g g e r signal obtained from
vertical deflection system.
+ LINE —: Trigger signal obtained
from a sample of the line voltage
applied to this instrument.
Determines the method of coupling
the trigger signal to the trigger circuit,
or the trigger mode.
AUTO ; Sweep automatically triggered
at the average level o f the applied
trigger signal when the trigger signal
repetition rate is above about 60
hertz. For lower repetition rates or
when an adequate trigger signal is
not applied, the sweep free runs at
a b o u t a 50 hertz rate. TRIG
LEVE L control is inoperative.
AC: Rejects DC and attenuates signals
below about 30 hertz. Accepts sig­
nals between about 30 hertz and
four megahertz. Triggering point
determined by TRIG LEVEL con­
trol.
DC: Accepts all trigger signals from
DC to fo ur megahertz or greater.
Triggering point determined by
TRIG LEVEL control.
Selects amplitude point on trigger sig­
nal where sweep is triggered.
Sets the time-base generator fo r trig­
gered or free-running operation. In the
fu lly counterclockwise PRESET posi­
tion, the time-base is automatically set
fo r triggered operation.
EXT TRIG INPUT Input binding post fo r external trigger
signal.
Sweep
T IM E /D IV Selects sweep rate of the time-base
generator (Variable T IM E /D IV control
must be in C ALIB R A TE D position fo r
indicated sweep rate).
Variable T IM E /
D IV (not labeled-
red knob concen­
tric w ith TIM E/
DIV switch)
Provides continuously variable uncali­
brated sweep rates between the cali­
brated settings selected by the T IM E /
DIV switch. UNCALIBRATED TIME
BASE light at lower right corner of
fro n t panel indicates when Variable
T IM E /D IV control is not in C A L I­
BRATED position.
Horizontal Display Determines horizontal mode o f opera-
(MAG-EXT HORIZ) tion.
X I MAG: Normal sweep at sweep rate
selected by the T IM E /D IV switch.
X5 MAG: Magnified sweep at sweep
rate five times faster than setting of
T IM E /D IV switch.
EXT HORIZ: Horizontal deflection
provided by an external signal con­
nected to the rear-panel EXT
HORIZ INPUT binding post.
Other
VER TICAL Controls vertical position o f the trace.
POSITION
H O R IZO N TAL Controls horizontal position of the
POSITION trace.
CALIBRATO R Selects the peak-to-peak amplitude of
the square wave available at the CAL
OUT binding post.
C AL OUT Calibrator output binding post.
UNCALIBRATED TIM E BASE: Light indicates that the
horizontal sweep rate is uncalibra­
ted.
VE R TIC A L: Light indicates that the
vertical deflection factor is uncali­
brated.
Screwdriver adjustment to provide cor­
rect operation of the instrument in the
PRESET position of the S T A B ILIT Y
control.
Rear Panel
VERT GAIN ADJ Screwdriver adjustment to set the gain
of the vertical amplifier.
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