MAINTENANCE HISTORY OF CHIP COMPARATOR MODEL 405-B SERIAL NO. 1 INSTALLED IN IAD

• Document Type: CREST
• Collection: NGA Records (Formerly NIMA)
• Document Number (FOIA) /ESDN (CREST): CIA-RDP78B04747A001500030042-7
• Release Decision: RIPPUB
• Original Classification: C
• Document Page Count: 3
• Document Creation Date: December 28, 2016
• Document Release Date: January 30, 2002
• Sequence Number: 42
• Publication Date: May 18, 1966
• Content Type: MFR

Approved For Release 200 IA-RDP78BO4747AO01500030042-7
NPIC/P&D6/1)16-1375
18 may 1966
!. 10RMDUM FOR THE RECORD
SUBJECT: Maintenance History of Chip Cc parator Model 405-R
Serial No. 1 installed in IAD
25X1A
1. Subject instrument was installed in November 1965. It has required
adjustment to correct counting emirs constantly sinee that time. Adjust--
rent of both Interferometer and O Trigger circuits are necessary.
2. Maintenance requests to EPS for correction -do not accurately reflect
the actual up-time of this inatrua"t due to infrequent use. The sequence
of events preceding a service call has been as follows
a. EPS adjusts and checks instrument. LAD may or may not use
instrument the same day.
b. RPS ehecke instrument the following day. Usually it is still
counting correctly, but not always.
c. The next time IAD attemps to use the instrument (may not be
for several days), it is not counting correctly in one or both
axes.
25X1A
3. On February 8. 1966, a representative of
Inc., performed the following maintenance on the Chip Comparator. 25X1A
a. Increased the output of the high voltage circuit for both the
X and Y axis.
b. Replaced a printed circuit board in the X axis circuit.
c. Adjusted the D.C. level of interferometer output signals for
both axes.
25X1 A a. Adjusted
DECLASS REVIEW by NIMA/DOD
Trigger circuits for both axes.
now 1
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25X1A 4. 1 was questioned as to why the interferometer circuits
required frequent adjustment. Ile felt that changes in ambient temperature
or line voltage fluctuations could be the cause, however, he had not
experienced this problem at other installations.
5. Since sufficient data to isolate the problem could not be obtained
25X1A during visit, EPS -agreed to maintain a detailed record of
future counting problems. He supplied a spare line voltage regulator to
be used to determine if voltage fluctuation was responsible. PS connected
the regulator, but no improvement resulted.
6. IAD agreed to make daily tests to help determine actual up-time of
the instrument, but they did not follow through. However, spot checks by
FPS showed that the counting problem still existed.
0
25X1A
is 8. concluded that the X-axis interferometer optics
required replacement, but he would have to return later for this operation.
Both axes were operating when he left at 1615 on k March 1966. A check
by BPS at 1000 on 7 March 1966, found the X-axis to be inoperative. Adjust-
ments could not be made due to the faulty interferometer optics.
9. On 5 and 6 April 1966,
25X1 A de the following repairs on the comparator.
a. Replaced X-axis mercury lamp.
b. Replaced X-.axis corner cube.
c. Aligned interferometer optics and digitizer circuits.
25X1
7. After approximately one month, was informed that the 9 tiX1A
counting circuits still required frequent adjustment, and on 3 and. 4 March 1966,
he returned to perform a series of tests. During his checks he repaired
bad solder connections in the oscillator power supplies of both axes and
replaced a bad capacitor in the Y-axis Schmidt circuit. He then set up both
axes and, after overnight operation obtained the following results.
a. Y--axis electrical drift was within tolerances.
b, X-axis electrical drift was within tolerances.
c. X-axis interferometer optics could not be aligned to allow an
adequate safety factor.
d. X--axis mercury lamp output appeared to be low.
of 25X1 A
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CONFIDENTIAL
10. Both axes were operating when they departed on 6 A=pril, and a
cheek by BPS on 9 April shoved that the*xes were still operating correctly.
However, on 11 April both axes required adjustment of the circuits 25X1 A
to compensate for interferometer signal level shift-
11 . During the remainder of the month of April, TAD did not use the
instrument due to lack of confidehes. Spot checks three times by EPS
discovered the need for adjustment of both axes. 'PS made the necessary
adjustments.
12. On 5 May 1966, a spot check by E found both axes not counting
S correctly. The X-axis could not be adjusted due to insufficient signal
snplitude near the stage limits. was informed that the 25X1A
X-axis was still malfunctioning, and on 11 may 1966, removed 25X1A
the X-axis interferometer and took it to his plant for study.
25X1A
Equipment Performance sec P&D~',
0
Approved For Release 2002/06/17 : CIA-RDP78B04747A001500030042-7