Tektronix 1401A Instruction Manual page 77

Calibration/Adjustment Procedure—1401A
7. Adjust Balance of Gating Circuit
a. Apply a signal to the 1401A INPUT. Tune the
CENTER FREQ to the signal frequency and open the
display to about 1 MHz/DIV with the FREQ SPAN
selector.
b. Switch the VERTICAL DISPLAY to LOG. Adjust
the signal level and/or GAIN of the 1401A so the signal
amplitude is full screen.
c. Connect a DC termination (50 {2 to 100 2) to the
GATE input connector and switch the GATE function
d. Adjust C948 and C949 (Fig. 6-16) for minimum
signal amplitude.
This concludes the Calibration procedure. The instru-
ment should now meet all requirements called for in the
Performance section.
NOTES