Tektronix 3B5, Инструкция по эксплуатации

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SECTION
2
OPERATING INSTRUCTIONS
General Information
To effectively use the Type 3B5, the operation and capa­
bilities of the instrument must be known. This section
describes the operation of the front-panel controls and con­
nectors, gives first time and general operating information,
External Mode programming information and lists some
basic applications for this instrument.
The Type 3B5 operates with the indicator oscilloscope and
an amplifier unit to form a complete oscilloscope system.
When used with an automatic programmable amplifier unit, a
remote-seeking probe and an external programmer, a com ­
plete system is formed which has manual, automatic seeking,
remote seeking and external programming measurement
capabilities.
Installation
CAUTION
Turn off the oscilloscope power before inserting
or removing the plug-in unit.
The Type 3B5 is designed for use in the Horizontal plug
in compartment of a 560-series indicator oscilloscope. How ­
ever, the Type 3B5 can be inserted into the Vertical plug-in
compartment of the indicator oscilloscope to provide a sweep
that runs vertically on the CRT screen (no blanking provided
and instrument may not meet performance requirements given
in Section 1 if used in this manner). Since the horizontal and
vertical deflection plate sensitivities of the oscilloscope are
different, the Type 3B5 must be recalibrated to provide an
accurate display for vertical deflection use. Throughout this
manual, it is assumed that the Type 3B5 is used to provide
horizontal deflection in the conventional manner.
To install the Type 3B5 in the oscilloscope, insert it into
the plug-in compartment and push it in as far as possible.
Be sure the securing latch at the bottom of the panel is out
of the way (turn knob counterclockwise) to prevent damage
to the oscilloscope front panel. Secure the plug-in into the
compartment by turning the securing-latch knob clockwise
until it is tight. To remove the plug-in from the compartment,
turn the securing-latch knob several turns counterclockwise.
Then, pull the plug-in partially out of the compartment with
the knob and take hold of the plug-in by the support rods
to remove it from the oscilloscope.
Whenever the Type 3B5 is transferred from one oscillo ­
scope to another, the sweep calibration should be checked
and adjusted if necessary to provide accurate measurements
with the complete system. See Horizontal Gain Adjustment
in this section for adjustment procedure.
Cooling
The Type 3B5 does not require special cooling other than
that provided by the indicator oscilloscope. When operated
within the ambient temperature range given in Section 1,
the Type 3B5 provides accurate measurements (note excep ­
tion for sweep accuracy).
FRONT-PANEL CONTROLS AND CONNECTORS
Introduction
All controls and connectors required for the operation of
the Type 3B5 are located on the front panel of the unit (see
Fig. 2-1). To make full use of the capabilities of this instru ­
ment, the operator should be familiar with the function and
use of each of these controls and connectors. A brief descrip­
tion of the function or operation of the front-panel controls
and connectors follows. More detailed information on con ­
trol operation and use is given under General Operating
Information.
Trigger Controls
EXT TRIG Input connector for external trigger signal.
INPUT
Trigger Function
(not labeled)
SLOPE
Lever switch which selects the trigger
source, coupling and mode.
INT-AUTO— Permits normal triggering on
repetitive waveforms with repetition
rates higher than 50 Hz. For lower repe­
tition rates or when there is no trigger
signal, the sweep generator free runs at
the sweep rate to which it is set to pro­
vide a reference trace. Auto Trigger
light indicates when unit is in the auto
trigger mode.
INT-AC — Sweep triggered by internal sig ­
nal from amplifier unit. Trigger circuit
rejects DC and attenuates AC signals
below about 50 Hz.
EXT-AC —Sweep triggered by external sig­
nal applied to the EXT TRIG INPUT con ­
nector. Trigger circuit rejects DC and
attenuates AC signals below about
50 Hz.
EXT-DC —Sweep triggered by external sig ­
nal applied to the EXT TRIG INPUT con ­
nector. Trigger circuit accepts AC and
DC signals.
(+) and (—) lights indicate which slope of
the trigger signal starts the sweep. When
the ( — ) light is on, the sweep can be trig ­
gered on the negative-going slope of the
trigger signal; the (+) light indicates that
the sweep can be triggered on the positive­
going slope of the trigger signal. Trigger
slope is changed by pressing the CHANGE
SLOPE button in the center of the LEVEL
control.
2-1