Tektronix 1S1 Instruction Manual page 12

10 k ohms. Measurement of offset voltage
should be made with high-impedance de-
vice.
SMOOTHING Reduces random display noise amplitude
Control when control is turned counterclockwise.
Noise may be decreased to approximately
rd of the value present at normal re-
sponse position (NORM). If display dot
density is low, smoothing reduces appar-
ent transient response of system.
PROBE POWER Provides filament and plate voltages and
Connector ground return for operation of cathode-
follower probe.
SIGNAL IN Provides 50-ohm environment for applying
Connector signal to input circuit of vertical system.
Connector is followed by trigger takeoff,
delay line, 50-ohm termination and sam-
pling gate. Dynamic operating range is
up to ±2 volts and maximum short-time
overload
(higher with reduced duty factor).
VERT OUTPUT Provides real-time replica of signal applied
Jack to oscilloscope vertical amplifier. Output
amplitude (through 10k ohms) is 200mv
per cm of calibrated display amplitude.
Includes dc offset voltage. If vertical signal
is driven out of dynamic range of sam-
pling amplifiers, signal at VERT OUTPUT
jack is distorted. Output signal can be
used in conjunction with horizontal output
to drive
oscilloscope.
VERT GAIN Adjust display amplitude to correspond to
Adjustment deflection factor indicated by mVOLTS/CM
switch,
control is at CAL position.
VAR BAL Adjusts vertical balance so that with zero
Adjustment offset voltage trace does not move verti-
cally when mVolts/Cm VARIABLE control
is rotated.
TRIGGER Selects triggering signal level that starts
SENSITIVITY trigger circuit operation. Adjusts frequency
Control of synchronizing circuit for operation on
highfrequency triggering signals when
RECOVERY TIME control is switched into
SYNC position.
RECOVERY TIME Adjusts duration of trigger holdoff interval
Control and SYNC so that recovery occurs between cycles of
Switch input triggering signal, thus providing
stable triggering regardless of triggering
signal repetition rate. Sets circuit for
synchronized operation when control is
switched to SYNC detent position at
counterclockwise end of rotation.
TRIGGER Selects triggering signal from vertical
SOURCE channel trigger takeoff or from EXT TRIG
Switch input connector. Also selects either posi-
tive-going ( + ) or negative-going ( - )
is approximately ±5
pen recorder or monitor
when mVolts/Cm VARIABLE
TRIGGERING
EXT TRIG
Connector
TIME/CM
volts
(MAGNIFIER)
Switch
Time/Cm
VARIABLE
Control
TIME
POSITION
RANGE
Indicator
TIME
POSITION
And
FINE
Controls
Operating Instructions – Type 1S1
slope of triggering signal. Disconnects
triggering signal and permits free run op-
eration of triggering circuit when switch is
set to FREE RUN position.
Permits application of external signal (ac-
coupled) for triggering sampling operation.
Primarily for use with small amplitude trig-
gering signals (from 5 mv to 200 mv) and
for obtaining time positioning not possible
with internal triggering. Also permits trig-
gering from a single source to retain time
relationships between different vertical in-
put signals and to avoid readjusting trig-
gering controls. One trigger is required
for each sample. For slowrise signals, 1
mv/µsec minimum rate of rise is required.
If triggering signal amplitude exceeds 200
mv, be sure to attenuate signal.
SWEEP
Operates with TIME POSITION RANGE
indicator to select display equivalent-time
sweep rate and time magnification. Cali-
brated steps range from 50 µsec/cm to 0.1
nsec/cm. Time magnification up to X100
is possible on sweep rates from 50 µsec/cm
to 1 nsec/cm, with no change in display
dot density. Magnification takes place
following a time reference point that re-
mains fixed at the left edge of the screen.
White dot on MAGNIFIER knob always
indicates display equivalent-time sweep
rate, even when magnified. Display is cali-
brated only when Time/Cm VARIABLE con-
trol is at CAL position and oscilloscope
horizontal deflection factor is adjusted to
1 volt/cm. Display repetition rate also
depends on display dot density and on
triggering signal repetition rote.
Varies equivalent-time sweep rate con-
tinuously between steps
switch. Sweep speed is increased from rate
indicated by TIME/CM switch as VARI-
ABLE control is turned clockwise. Can ex-
tend fastest sweep rate (.1 nSEC/CM) to
about 33 psec/cm. When making time
measurements from display,
VARIABLE control is set to CAL position
(counterclockwise detent).
Indicates time range through which TIME
POSITION and FINE controls can move
start of crt display "time-window." Range
is read on blue TIME POSITION RANGE
scale, as indicated by blue tab on clear
skirt of knob.
Position start of sweep through time range
indicated by TIME POSITION RANGE
indicator to move display time window
and to position time-reference point for
magnification. Fully clockwise
of each control provides minimum sam-
pling delay (maximum lead time).
of TIME/CM
be sure
position
2-3