Tektronix 1S1 Instruction Manual page 86

Amplitude Calibrator
Display
Millivolts/Cm
Input Atten
Millivolts/Cm Variable
Vc Range
Comparison Voltage
Input Coupling
(Channel A)
Input Coupling
(Channel B)
14. Adjust Memory Balance
a. Test equipment setup is shown in Fig. 5-26.
b. With the Type 1S1 DC OFFSET control, position the
trace near the center of the indicator oscilloscope crt screen.
c. Turn the SMOOTHING control rapidly from one end
of its range of rotation to the other end.
d. Check that the indicator oscilloscope trace does not
move vertically more than about 0.5 cm as the SMOOTH-
ING control is turned.
Fig. 5-27. Location of balance adjustment controls on left side of Type 1S1. (Unit is installed in indicator oscilloscope.)
Off
A-Vc
50
1
Calib (at detent)
0
4.000
Gnd
Gnd
e. Adjust R110 (MEMORY BAL) if operation of the
SMOOTHING control is not correct. See Fig. 5-27 for the
location of R110.
f. Reset the SMOOTHING control to NORM position
(fully clockwise).
15. Adjust Bridge Balance
a. Connect the test probe to the Type 1S1 OFFSET OUT-
PUT jack. (You may wish to use a banana plug tip on
the probe for this connection.)
b. Free run the test oscilIscope trace and set it for a
zero-volt dc reference level.
c. Set the test oscilloscope Input Coupling switch to Dc.
d. Adjust the Type 1S1 DC OFFSET control to position
the test oscilloscope trace at the zero reference level, in-
dicating a dc level of zero volts at the OFFSET OUTPUT jack.
e. Switch the Type 1S1 mVOLTS/CM switch to each of
its 7 positions.
f. Check that the indicator oscilloscope trace does not
move more than about ±2cm as the switch is turned throughout
its range.
g. Adjust R30 (BRIDGE BAL) if operation of the switch
is not correct. See Fig. 5-27 for the location of R30.
Calibration – Type 1S1
5-23