Tektronix 323, Инструкция по эксплуатации

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Operating Instructions— Type 323
POSITION
X 10 VERT
GAIN
Horizontal
Controls
TIME/DIV
VARIABLE
VAR
(EXT HORIZ)
POSITION
Potentiometer. Sets the trace vertical DC
reference position. Determines the no-signal
vertical position of the CRT beam by set­
ting the DC voltage applied to the vertical
deflection plates.
A slide switch attached to the Vertical
POSITION shaft. It increases vertical gain
by a factor of 10 when pulled out. (The
vertical deflection factor selected by the
VOLTS/DIV-VARIABLE combination is ef­
fectively divided by 10 when this control
is pulled out.) A yellow band around the
switch shaft becomes visible to indicate
that X 10 VERT GAIN is in effect.
Rotary switch. Selects calibrated sweep
rates from 5 /xS/DIV to 1 S/DIV. Value in­
dicated only applies when VARIABLE
(TIME/DIV) is set at CAL and the X 10
HORIZ MAG is pushed in. At EXT HORIZ
position it permits horizontal trace deflec­
tion as a result of a horizontal input signal,
the EXT TRIG OR HORIZ ATTEN control
setting, and the horizontal amplifier de­
flection factor. The approximate EXT
HORIZ deflection factor is 0.25 V /div and
changes to about .025 V /div when the
X 1 0 HORIZ MAG knob is pulled out.
These values can be increased 10 times by
using the VAR (EXT HORIZ) control.
Potentiometer. Can be varied to select
any sweep rate between the value se­
lected by the TIME/DIV switch-XlO
HORIZ MAG combination and 40% off
that value.
Any sweep rate between
.5 /xS/DIV and more than 2.5 S/DIV can
thus be selected. When at CAL position
it provides calibrated sweep rates as se­
lected by the TIME/DIV— X 1 0 HORIZ
MAG combination.
Potentiometer connected to same control
knob as VARIABLE (TIME/DIV). With EXT
HORIZ selected by the TIME/DIV switch,
the VAR control can vary the external hori­
zontal deflection factor from approximately
0.25 V /div to 2.5 V /div with the EXT TRIG
OR HORIZ ATTEN switch in the 1 Xposition
and the X 1 0 HORIZ MAG knob pushed in.
Placing the EXT TRIG OR HORIZ ATTEN
switch to the 10X position increases these
values by a factor of fen; pulling the X 10
HORIZ GAIN control out decreases the
values by a factor of 10.
Potentiometer. Sets the starting point of
the horizontal sweep. When the TIME/DIV
switch is at the EXT HORIZ position, if
determines the horizontal position of the
CRT beam by setting the DC voltage ap­
plied to the CRT horizontal deflection
plates. Coarse and fine control potenti­
ometers with a 10:1 ratio are connected to
the POSITION shaft. The fine control has
30° of rotation independent of the coarse
control. This back-lash arrangement per­
mits the use of a single knob for coarse
and fine adjustments, with the coarse ad­
justment during X I HORIZ MAG being
equal to the fine adjustment during X 10
HORIZ MAG operation.
X 10 HORIZ A slide switch attached to the Horizontal
MAG POSITION shaft. When it is pulled out, the
horizontal sweep rate selected by the TIME/
DIV-VARIABLE combination is effectively
divided by 10. The 1 division of trace
that previously straddled the graticule
vertical center is thus expanded to cover
the full length of the graticule. Any 1
division of the sweep can be displayed as
a 10 division trace by combined use of the
Horizontal POSITION control and the X 10
HORIZ MAG.
With the TIME/DIV switch at EXT HORIZ
position, pulling the X I 0 HORIZ MAG out
increases the deflection caused by a
HORIZ INPUT signal by a factor of 10.
A yellow band around the switch shaft
becomes visible to indicate that X10
HORIZ MAG is in effect.
TRIGGER
Trig/Horiz
Coupling
Switch
A combination of rotary switch wafers and
a center tapped potentiometer. Selects
positive (+ ) slope triggering level when
the knob's indicator spot is to the left
of the knob’s vertical center; selects neg­
ative (—) slope triggering level when the
knob's indicator spot is to the right of the
knob’s vertical center. The indicator spot
versus the plus and minus waveform slopes
(which appear alongside the TRIGGER
knob) indicates the approximate point on
the waveform at which triggering occurs.
When the control is at the counterclock­
wise ( + AUTO) or clockwise (— AUTO)
limit, a baseline of relatively constant
brightness is automatically provided dur­
ing the absence of triggering signals. In­
put signals whose frequencies are higher
than that of the automatic base line gen­
erator override it to trigger the baseline.
Four position lever switch; selects the
source and type of triggering; also selects
EXT HORIZ INPUT coupling mode.
INT TRIG Selects Internal AC triggering signal; the
ACLF REJ triggering circuit is de-sensitized to signals
below about 30 kHz.
AC Selects Internal AC triggering signal.
EXT TRIG Refers to External Horizontal input cou-
OR HORIZ pling when TIME/DIV is in EXT HORIZ
position; refers to External Trigger cou­
pling mode in all other positions of TIME/
DIV switch.
AC Selects external AC triggering signal.
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