Tektronix 1A5 Instruction Manual page 55

d. CHECK — Vc AMPLITUDE index is within 1 line width
of 0-0-0.
e. Switch POLARITY to +.
f. CHECK — Comparison voltage under each setup given
in Table 5-2.
TABLE 5-2
AMPLITUDE
0-0-0 (CCW)
1-0-0
2-0-0
3-0-0
4-0-0
0-0-0 (CW)
Switch POLARITY to -
0-0-0 (CW)
4-0-0
3-0-0
2-0-0
1-0-0
0-0-0 (CCW)
g. Switch VOLTS / CM to 5 V and rotate AMPLITUDE clock ­
wise to 0-0-0.
h. CHECK ------ 0 . 5 V ± 5 mV MO
i. S w itch POLARITY to + .
j. CHECK — + 0. 5 V ± 5 mV MO
k. Use of the voltmeter has been completed. Disconnect
the cable from the MO N I TOR jack.
7. Check POSITION Control Range
REQUIREMENT — 12 cm or more range.
a. Rotate POSITION fully clockwise.
b. Rotate Vc AMPLITUDE counterclockwise until the trace
is positioned to the +3 cm line.
c. Using the POSITION control, move the trace down 6 cm
to the — 3 cm line.
d. Switch the DISPLAY control to Vc — B.
e. Again rotate the Vc AMPLITUDE control counterclock ­
wise until the trace is positioned to the +3 cm line.
f. CHECK-POSITION range.
fully counterclockwise. Trace should move to or below the
— 3 cm line for a total of 12 cm or more POSITION con ­
trol range.
g. Switch POLARITY to 0.
8. Check STEP ATTEN BAL Control Range
REQUIREMENT — 20 mV or more range.
a. Switch VOLTS/CM to 5 mV.
Volts
0 ± 0.005
+ 1 ± 0.005
+2 ± 0.010
+3 ± 0.015
+4 ± 0.020
+ 5 ± 0.025
– 5 ± 0.025
– 4 ± 0.020
– 3 ± 0.015
– 2 ± 0.010
– 1 ± 0.005
0 ± 0.005
N I TO R ou t pu t.
NI TOR output.
Rotate POSITION control
Performance Check — Type 1A5
b. Using the POSITION control, set the trace to graticule
vertical center.
c. CHECK — Rotate STEP ATTEN BAL from limit to limit.
4 cm (20 mV) or more trace movement should result.
d. Using the STEP ATTEN BAL, reset the trace to graticule
vertical center.
9. Check Microphonics
REQUIREMENT — 100 μ V or less microphonics.
a. Switch B Input AC-GND-DC control to GND, VOLTS/
CM to 1 mV and DISPLAY to A-B.
b. CHECK — 1 mm or less oscillation or ringing results in
response to tapping finger tips against the front panel.
10. Check Input Transistor Gate Current
REQUIREMENT — 0.1 nA or less gate current.
a. Attach a 50-Ω GR-to-BNC termination to the center of
the flexible T connector.
b. CHECK — 1 mm or less trace shift occurs at the instant
the A Input AC-GND-DC control is switched to AC.
turn the control to the GND position.
c. CHECK — 1 mm or less trace shift occurs at the instant
the B Input AC-GND-DC control is switched to AC.
turn the control to the GND position.
d. Remove the flexible T connector from the A and B IN ­
PUT connectors.
11. Check Noise
REQUIREMENT — 50 μ V RMS or less.
a. Connect the following components to the A INPUT con ­
nector in the sequence listed:
GR-BNC 50-Ω Termination
GR 5 ns Cable
2-101 50-Ω GR Attenuators
1 - 5:1 50-Ω GR Attenuotor
Type 106 Square Wave Generator Fast Rise + Output
b. Set the oscilloscope Time/CM control to lOµSec and
the Triggering Level fully clockwise.
c. Set the Type 1A5 A Input AC-GND-DC control to DC.
d. Set the Square Wave Generator controls as follows:
Repition Rate Range
Multiplier
Hi Amplitude/Fast Rise
e. Adjust the Square Wave Generator + Transition Ampli ­
tude to provide 2 separate traces. (Caused by the upper
and lower excursions of the square wave being presented
on an untriggered sweep.)
Re ­
Re ­
1 kHz
CCW
Fast Rise
5-3