TM 11-6625-2575-14
NOTE
In some cases, the adjustment and alignment procedures may require a compro-
mise between two or more characteristics. When the procedures in section V
are completed, perform the test procedures in section IV.
g. Return the CRT display to the horizontal
7-12. Power Supply Adjustment
positions obtained in d and e above.
CAUTION
h. Set the SWEEP RATE switch to the .05 to
Adjustment of power supply voltages
5 Hz position. Do not change oscilloscope con-
may cause major misalignment. Do not
trols.
adjust voltage before checking both
LOW and HIGH BAND CENTER
tracing a rectangular pattern counterclockwise.
j. Adjust the lower trigger point control
(R108) so the upper left-hand corner of the rec-
tor the voltages as in table 7-1. Do not make ad-
tangle is visually aligned at the upper left-hand
justments if voltages are within tolerances.
corner of the graticule.
b. If required, adjust R7 to obtain a voltage
k. Adjust the upper trigger point control
reading of +30 volts dc 1. The peak-to-peak rip-
(R101) so the upper right-hand corner of the rec-
ple as measured with an at-coupled oscilloscope
tangle is visually aligned at the upper right-
is 6 mV (typical).
hand corner of the graticule.
c. If required, adjust R14 to obtain a voltage
l. Repeat j and k above as required until both
reading of -30 volts dc 1. The peak-to-peak
conditions of alignment occur simultaneously. Do
ripple as measured with an at-coupled oscillo-
.
not change the oscilloscope controls.
scope is 4 mV (typical).
m. Set the SWEEP RATE switch to LINE.
d. If required, adjust R21 to obtain a voltage
n. Adjust the line trigger amplitude control
reading of +200 volts dc 5. The peak-to-peak
(R119) and the line DC level control (R106) un-
ripple as measured with an at-coupled oscillo-
til a rectangular pattern of the same size as that
scope is 15 mV (typical).
obtained in j through e above is displayed.
7-13. Rate Generator Alignment
o. Repeat the alternate adjustments of R119
and R106 until the rectangular pattern is aligned
To align the rate generator, perform the proced-
with the respective graticule corners.
ures in a through o below.
7-14. Frequency Dial Alignment
b. Set the SWEEP RATE switch to MANUAL.
c. Misalignment may be caused by dial slippage,
by aging of components, or by incorrect settings
c. Adjust the SWEEP RATE vernier control
of the regulated power sources.
from one extreme to the other.
a. Dial Slippage.
d. Adjust the horizontal gain and horizontal
(1) Check the HIGH BAND.
(2) If the dial error is greater than one di-
the CRT display is visually aligned with the ex-
vision at 1200 MHz and is either constant or
treme left-hand vertical graticule line when the
erratic cover the HIGH BAND, slippage may
SWEEP RATE vernier control is fully counter-
have occurred.
clockwise.
(3) Adjust the two #6 setscrews that se-
e. In combination with d above, adjust the os-
cure the dial-venier collar to the oscillator shaft.
cilloscope controls so the dot on the CRT display
Use a 1/16-inch hex key. The collar is located
is visually aligned with the extreme right-hand
vertical graticule line when the SWEEP RATE
vernier control is fully clockwise.
(4) Position the shaft as required to release
f. The SCOPE HORIZ voltage should be 1.0
and then properly reposition the dial for fre-
volt 0.5 in d above and 18 volts 2 in above.
quency alignment.