Tektronix 221, Инструкция по эксплуатации

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FUNCTIONS OF
CONTROLS AND CONNECTORS
Section 2 —221 Service
A ll controls and connectors necessary for operation of
the 221 are located on the right side panel of the
instrument. See Fig. 2-1. A brief description of each control
and connector is given here.
V O LT S /D IV —selects vertical deflection factor (VAR
VO LTS/DIV must be in the CAL position for indicated
deflection).
STEP ATTEN B A L—screwdriver adjustment to balance
the vertical system for minimum trace shift when changing
deflection factors.
Vertical POS—controls the vertical position of the trace.
VERT G A IN —screwdriver adjustment to set the gain of
the vertical system.
VAR V O LT S /D IV —provides a continuously variable
deflection factor between the calibrated settings of the
VO LTS/DIV switch.
INPUT COUPLING—selects method used to couple the
input signal to the vertical amplifier system.
AC—blocks dc components of input signal. Low
frequency lim it (—3 dB point) is about two hertz.
GND—Input circuit is grounded. The applied signal is
connected to ground through a large resistor to provide a
precharge path for the AC input coupling capacitor.
DC—A ll components of the input signal are passed to the
vertical amplifier system.
SEC/DIV selects the sweep rate (VAR SEC/DIV must be
in the CAL detent; HORIZ MAG must be in X I position,
for indicated sweep rate). 1 V position allows fo r X-Y
operation w ith the horizontal deflection provided by the
signal connected to the EXT TRIG OR HORIZ INPUT
jack.
Horizontal POS—controls the horizontal position o f the
trace.
VAR SEC/DIV—provides continuously variable sweep
rates between calibrated settings of the SEC/DIV switch.
Extends the minimum sweep rate to about
0.5 second/division.
HORIZ MAG—X10 magnifier to increase the maximum
sweep time to 0.1 microsecond/division and provides a
horizontal sensitivity of 0.1 volt/division in X-Y operation.
Fig. 2-1 Side panel showing controls and connectors.
REV. B, FEB. 1977
2-1