Tektronix 442, Инструкция по эксплуатации

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Operating Instructions—442 Service
NOTE
Channel 1 (X) is the horizontal (X-axis) signal input
and Channel 2 (Y) is the vertical ( Y-axis) signal input
when the 442 is set for X-Y operation. The
TRIGGERING SOURCE switch must be set to X-Y
and the VERT MODE CH 2 button must be pressed in
for X-Y operation. The horizontal POSITION control
determines the X-axis signal display position and the
channel 2 POSITION control determines the Y-axis
signal display position when operating in the X-Y
mode.
n(f) VAR (Variable volts/divislon controls for Channel
1 and Channel 2)
When rotated out of the calibrated (fully
clockwise detent) position, these controls
provide continuously variable (uncalibrated)
deflection factors
between the calibrated
positions of the VOLTS/DIV switches. Extends
maximum deflection factors to 25 V/div with
VOLTS/DIV switches set to 10 (volt) position and
VAR rotated fully counterclockwise. VAR con­
trols must be set to the detent position for
calibrated deflection factors.
NT) CH 2 (Y) (Channel 2 or Y-axis input)
Activated when the VERT MODE CH 2 button is
pressed in. Bnc connector for the application of
external signals to the channel 2 vertical deflec­
tion system (see Note for X-Y operation).
(l? ) AC-GND-DC (Input coupling switches tor
Channel 1 and Channel 2)
Three-position lever switches that select the
method of internally coupling the vertical input
signals to the vertical amplifier input.
Yf) VOLTS/DIV (Channel 1 and Channel 2)
Switches that select the vertical def I ecti on factors
in a 1-2-5 sequence. The item 18 VAR controls
must be in the calibrated (detent) position to
obtain the deflection factors indicated by the
switch settings. The correct deflection factor
when using a IX probe or cable is read from the
IX (left) knob skirt window position, and the
correct deflection factor when using a 10X probe
is read from the 10X (right)
knob skirt window
position.
AC: Signals are coupled capacitively. Any dc
signal component is blocked. Low fre­
quencies are attenuated (3 dB down at
about 1 Hz using a 10X probe). Ac
coupling causes tilting of square waves
below 1 kHz.
GND: Grounds the input of the vertical
amplifier to provide a ground reference
display. Connects the applied signal to
ground through the input coupling
capacitor and a 1 MQ resistor to allow
the input coupling capacitor to be
precharged by the input signal.
DC: All frequency components of the input
signal are passed to the vertical
amplifier.
Figure 2-6. Controls and switches accessible through the
bottom of the
442 cabinet. Figure 2-7. Vertical system controls.
REV A MAY 1980
2-5