LETTER (SANITIZED) FROM (SANITIZED)

• Document Type: CREST
• Collection: General CIA Records
• Document Number (FOIA) /ESDN (CREST): CIA-RDP78-03330A004200080009-4
• Release Decision: RIPPUB
• Original Classification: C
• Document Page Count: 2
• Document Creation Date: December 27, 2016
• Document Release Date: May 8, 2014
• Sequence Number: 9
• Publication Date: November 11, 1960
• Content Type: LETTER

Declassified in Part - Sanitized Copy Approved for Release 2014/05/08: CIA-RDP78-03330A0042-00080009-4
UUNtiumiliAL50X1
November 11, 1960
Dear
P1,414-e-
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- DC - E
_
Enclosed please find Technical Report Number 2 on the
development of AP-3 and PS-10 power supplies.
Very truly yours,
Enclosure
ORIGINAL: et. BY g 3 5 q
DEM. it REIM ON
EXT BYND 6 YRS BY
REASON 3
OC REV DATE JULNa_ BY elEYEE0
ORM COMP OPI 4276? TYPE
?RIO CLASS AL_ PAGES REV CLASS
JUST NEXTP41- NEXT REV AUTH: 70.1
CONFIDENTIAL
Declassified in Part - Sanitized Copy Approved for Release 2014/05/08: CIA-RDP78-03330A004200080009-4
50X1
50X1
50X1
50X1
50X1
50X1
Declassified in Part -Sanitized Copy Approved for Release 2014/05/08: CIA-RDP78-03330A004200080009-4
luriutil 1 IHL
November 8, 1960
Report of progress on development of AP-3 and PS-10 Power Supplies
In the last 2 1/2 weeks we have finally been able to make substantial progress
on the development of these power supplies. Prior to this time we had been
waiting for delivery of a prototype miniature power transformer from both
suppliers (Malmac and United Transformer Co.) with whom we had placed
orders. Both transformers arrived nearly simultaneously. The Malmac unit
is the smaller of the two and we spent about one week working on a design
based upon its use, since the package size if we used this transformer would
be smaller. A careful investigation, however, showed that this transformer
was not satisfactory and that the manufacturer had gone too far in miniaturi-
zation. It did not meet the necessary electrical requirements. The trans-
former from U. T. C. was then tried in our circuit and was found to perform
satisfactorily. However, this transformer was designed using a "C" core
and results in a certain amount of wasted space. We have now determined that
a compromise between these two transformer types is possible and will result
in our obtaining the required performance in this smaller possible transformer
size, and we are having the compromise transformer built for us at the present
time. Using this transformer, the package size for the miniature supply will
be 7.5" X 4.6" X 2.5".
In this package size, no compromise with the original electrical performance
specification is required. The 2 Ampere regulated output can be delivered
continuously and the 5 Ampere unregulated output can be delivered on a con-
tinuously occurring 50% duty cycle. In the battery charging mode of operation,
4 Amperes can be delivered continuously. With the test battery we have here,
this results in fully charging the battery in less than two hours. It should be
pointed out that charging the battery at this rate can be dangerous if the opera-
tion is not monitored and charging discontinued when the battery is fully charged,
because the final charging current is about 2 Amperes. There is no meter in-
dication that the battery is charged. The condition of the battery will have to
be monitored visually and the power supply disconnected when the battery is
fully charged.
The electrical performance, as far as ripple, regulation and stability is con-
cerned, is excellent and well within the original specifications. Delivery of
the final version of the transformer is expected in ten days, and the final packag-
ing of the supply will then take place.
50X1
50X1
Vice President
CONFIDENTIAL
Declassified in Part - Sanitized Copy Approved for Release 2014/05/08: CIA-RDP78-03330A004200080009-4