Atec Tektronix-1502 - Manual (Page 54)

TM 9-4935-601-14-3&P
Adjustment Procedure
Fig. 4-12. Reflected-Fall Time Check.
106. Remove the 50 n terminator and check
that the trace shift is less than 1/2 division.
107. Adjust-R1659(DC BAL) located on the
MAIN board, for the minimum trace shift between
the terminated and unterminated pulse.
Vertical Attenuation
108. Turn the 1502 top side up on the
bench.
109. Set the mp/DIV to 500, and turn ZERO
REF fully clockwise.
110. Set the DM 501 RANGE/FUNCTION
switch to 2 on the DC VOLTS scale.
111. Connect the lead from the DM 501 LO
terminal to the ground braid of P21 (on the VERT
AMP/SLOW RAMP board).
112. Connect the lead from the HI terminal
to the left end of R2229. See Fig. 4-13 for the
proper connection points.
113. Set the 1502 ZERO REF and
POSITION controls so that the DVM reads 1.000
0.008 volt. If the POSITION control cannot be
adjusted to obtain this reading on the DVM, adjust
R1659 (DC BAL) located on the MAIN board, for a
fully counterclockwise setting. Then adjust the
POSITION control for a DVM reading of 1.000
±
0.008 volt.
Figure 4-11. Loop Gain Adjustment.
REV D JUL 1980
4-16