Check Step Atten Bal (R129) Range - Tektronix 1A5 Instruction Manual

12. Check STEP ATTEN BAL (R129) Range

a. Equipment setup is shown in Fig. 6-11, except as follows:
No connections to the A INPUT connector are required; A
Input AC-GND-DC control is at GND.
b. Switch POLARITY to 0.
c. Set VOLTS/CM to 5 mV and set STEP ATTEN BAL to
midrange. Check that the UNCAL lamp is off.
d. Using POSITION control, set trace to vertical center of
graticule.
e. CHECK — Rotating STEP ATTEN BAL from limit to limit
moves the trace 4 cm or more (20 mV).
f. Return STEP ATTEN BAL to midrange and VOLTS/CM to
20 mV.
Calibration — Type 1A5
6-13