Tektronix 2445, Instruction Manual

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Section 1—2445 Service
SPECIFICATION
INTRODUCTION
The TEKTRO NIX 2445 Oscilloscope is a portable
150-MHz instrument having a four-channel vertical deflec­
tion system. Channel 1 and Channel 2 provide calibrated
deflection factors from 2 mV per division to 5 V per
division. For each of these channels, input impedance is
selectable between two values: either 1
in parallel
w ith 15 pF, or 50 £2 internal termination. Input-signal
coupling w ith 1-M£2 impedance can be selected as either
AC or DC. Channel 3 and Channel 4 have deflection factors
of either 0.1 V or 0.5 V per division. Each of these channels
has an input impedance of 1 M£2 in parallel w ith 15 pF,
w ith DC input-signal coupling. Trigger circuits enable stable
triggering over the full bandwidth of the vertical system.
The horizontal deflection system provides calibrated
sweep speeds from 1.5 s per division to 1 ns per division.
Drive for the horizontal deflection system is obtained from
a choice of A, B delayed, A alternated w ith B delayed
sweeps, or CH 1 (for the X-Y display mode).
The 2445 incorporates alphanumeric c rt readouts o f the
vertical and horizontal scale factors, the trigger levels,
time-difference measurement values, voltage-difference
measurement values, and certain auxiliary information.
The 2445 Oscilloscope is shipped w ith the following
standard accessories:
2 Probe packages
1 Snap-lock accessories pouch
1 Zip-lock accessories pouch
1 Operators manual
1 Service manual
1 Power cord (instaiied)
1 2-A, 250-V fuse
1 Clear plastic crt filte r
1 Blue plastic crt filte r (installed)
1 Front-panel cover
1 Operators pocket reference guide
For part numbers and further information about both
standard and optional accessories, refer to either "Options
and Accessories" (Section 7) in the Operators manual or
the Accessories information at the rear of this manual.
Your Tektronix representative or local Tektronix Field
Office can also provide accessories information and
ordering assistance.
PERFORMANCE CONDITIONS
The following electrical characteristics (Table 1-1)
are valid for the 2445 when it has been adjusted at an
ambient temperature between +20°C and +30°C, has had
a warm-up period of at least 20 minutes, and is operating
at an ambient temperature between —15°C and +55°C
(unless otherwise noted).
Items listed in the "Performance Requirements" column
are verifiable qualitative or quantitative limits that define
the measurement capabilities o f the instrument.
Environmental characteristics are given in Table 1-2.
The 2445 Oscilloscope meets the environmental require­
ments of MIL-T-28800C fo r Type III, Class 3, Style C
equipment; tested as per paragraph 4.5.5.1.2.2 for hum idity,
4.5.5.1.3 for low temperature, and 4.5.5.1.4 for high
temperature.
Mechanical characteristics of the 2445 are listed in
Table 1-3.
1-1