Ectron 560H, Инструкция по эксплуатации

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SECTION VII
7
CALIBRATION AND MAINTENANCE
GENERAL
The calibration controls can be identified on the
circuit board by reference designation. Instructions
for their proper use and associated test procedures
are given in the following paragraphs. The Model
560H to be tested must be energized and allowed
to reach thermal stability. Ectron recommends a
warm-up period of 30 minutes.
TEST EQUIPMENT REQUIRED
POWER SUPPLY
Fluke Model 731B or equivalent 10 V dc
supply.
PRECISION VOLTAGE DIVIDER
ESI Model RV622A. The divider must have an
input impedance of 10 k

.
DIFFERENTIAL OSCILLOSCOPE
Tektronix 5110 main frame, with 5B10N time
base and 5A21 differential amplifier or equiva-
lent. Be sure the oscilloscope has been
adjusted for common-mode rejection accord-
ing to the manufacturer’s instructions as
differential measurements are used in the
following procedure.
SWITCHES
Five Single-pole two-position
One Single-pole three-position
RESISTORS (CARBON FILM OR
COMPOSITION, ¼ W)
One 100

Two 350

Three 1 k

One 100 k

NULL DETECTOR
Keithley Model 155 or equivalent.
FUNCTION GENERATOR
Wavetek Model 180 or equivalent.
RMS METER
HP Model 427A or equivalent.
MATING CONNECTOR
The mating connector for the amplifier card-
edge J1 is a Cinch 50-18-A-20 (Ectron P/N
1-314018-0) which must be keyed between
Pins 5 and 6.
DMM
HP Model 3478A or equivalent.
PRELIMINARY ADJUSTMENTS
(FIGURE 7-1 )
1. Set all switches to 1.
2. Set the voltage source PS1 to 10.000 V dc
±0.1 V dc.
3. Adjust both inputs of the oscilloscope to
10 mV/cm dc.
4. Set S3 to 2.
5. Set S1 from 1 to 2 several times and adjust
the differential input balance on the
oscilloscope for minimum deflection.
6. Restore S1 and S3 to Position 1.
ZERO ADJUSTMENTS (FIGURE 7-1 )
All of the following adjustments are made with all
switches in Position 1 and Jumper J1 installed.
RTO means referred-to-output. RTI means
referred-to-input.
RTO
1. Set the amplifier gain to 5. Connect the
DMM to A2, Pin 1 and adjust R49 for 0 V
±1 mV.
2. Connect the DMM to A3, Pin 1 and adjust
R48 for 0 V ±1 mV.
3. Set S6 on the amplifier (RTO Range Switch)
to the 0.1 position.
4. Connect the DMM to A2, Pin 7 and adjust
R107 for 0 V ±1 mV.
RTO (OPTIONS K, L, M, AND N)
The offset on the filter assembly may be
adjusted to equal the offset at the wideband
7-1