Inspection Report No. 3 - AS-12(Classified)

• Document Type: CREST
• Collection: General CIA Records
• Document Number (FOIA) /ESDN (CREST): CIA-RDP78-02820A001200060006-6
• Release Decision: RIPPUB
• Original Classification: S
• Document Page Count: 5
• Document Creation Date: December 9, 2016
• Document Release Date: May 15, 2001
• Sequence Number: 6
• Publication Date: November 14, 1966
• Content Type: MF

Approved For Release 2001/07/28 : CIA-RDP78-0282OA001200060006-6
OPTIONAL FORM NO. )0 3010-107
MAY 1962 EDITION
GSA GEN. REG. NO. 27 v4w
UNITED STATES GOVERNMENT
Memorandum
25X1A5a1
TO The Files: Contract No.
__ 25X1A9a
FROM Mr.
mew
SUBJECT: Inspection Report No. 3 - AS-12 with
1. Project Description:
Approximately three months of on-the-air tests will be conducted
to determine how well the AS-12 operates,-what ionospheric phenomena
permit or prevent it from working, what changes should be included
in future units, and what are the best procedures for operating
the AS-12.
2. Contractual Information:
a. Initial Cost:
b. Request for Procurement Action: l April 1966
c. Initiation Date: 2 May 1966
d. Completion Date: 28 February 1967
e. Deliverable Items: Monthly progress letters, final report
3. Date of Meeting: 2 November 1966
I+. Place of Meeting:
~. Persons Attending:
Lgency
Contractor's Performance:
a. On schedule and expected to remain so: Yes
b. Within obligated funds and expected to remain so: Yes
c. Satisfactory technical progress: Yes
Project Status:
Security
A site survey was conducted by Messers 25X1A9a
was selected for the 2000 km tests 25X1A6a
Buy U.S. Savings
Approved For Release 2001/
25X1A5a1
25X1A5a1
25X1Ala
Non-Agency
. EP 66-241
DATE: 14 November.1966
oll Savings Plan
1200060006-6
 Approved For Release 2001107/28 : CIA-RDP78-0282OA001200060006-6
SUBJECT: Inspection Report No. 3 - AS-12
Project Status:
25X1A5a1
25X1A5a1
and , was selected for the 2 00 km tests.
There is no 2 hour State Police office in The Office
of Logistics Security Staff approved the use of city police for equip-
ment storage.
111L_ . ,_ Lb JJ V.LL U11C UVUJ1VULq.
His duties will be performed by Mr. who has been handling 25X1A5a1
security matters on this program.
Subcontract
Polaroid prints of the sounder receiver readout have been. coming
in weekly with the field log. The first contact prints were received
on 14 October. The first IBM printout (which is where the detailed
information is contained) was received on 24 October.
A transistor failed in the sounder transmitter programmer timer
during the week of 17 October. The technician at the site
accomplished the necessary repair after telephone consultation with
The equipment was down for less than one day.
25X1A6a
25X1A6a
25X1A5a1
A power supply transformer failed in the sounder transmitter 25X1A5a1
the week of 24 October. Mr. echnician
who is operating the sounder receiver, traveled to the base station
and replaced the supply with a unit shipped from the plant. Equip-
ment was down for three days.
AS-12 Base Transmitter
The output power of the base transmitter dropped significantly
on 31 October. The power amplifier is a seven stage distributed
amplifier consisting of 14 4CX350A tubes.'-Arcing was observed in
several of these tubes, and a number of cathode resistors and grid
resistors were cracked and burned. The trouble was traced to a tube
that had a grid to cathode short. Two tubes and several resistors
were replaced. The,unit was back in operation on 2 November. A
full complement of spare tubes was ordered. It is estimated that the
tubes-presently in the amplifier have been operated for about 500
hours.. It is not unusual to expect failures after that period of
time.
E1
Approved For Release 2001/07/28: CIAADP78-02820A001200060006-6
EP 66-241
 Approved For Release 2001/07/28 : CIA-RDP78-0282OA001200060006-6
""SUBJECT: Inspection Report No. 3 AS-12
7. Project Status:
AS-12 Field Team
Field equipment has been o eratin
problem has developed. Mr.
EP 66-24+1
.,
25X1A5a1
25X1A5a1
satisfactorily
but a staffing
25X1A5a1
,,
25X1A6a
has had to return to
for medical reasons and will be unable to return to the field. 25X1A5a1
has not found a cleared technician who is willing to assume Mrs 25X1A5a1
field assignment on a permanent basis. This will result in unanticipated
travel costs by rotating personnel to the field. appeared
only marginally concerned over this, and offered no alternative. 25X1A5a1
AS-12 Base Receiver
A serious problem has developed. The noise level at the receiver
site, as measured by the interference detection unit (IDU), has risen
to the extent that operation is virtually suspended. (AS-12 system
operation permits soundings only on channels that are clear at the
base. No clear channels equate to no operation.) The type of inter-
ference being experienced is QRM from distant locations. Several
weeks ago the probability of sounding on given channels was being
measured as typically .9. Now this probability on these same channels
has dropped to .4 and less. - is trying to attribute this to
the change of season with attendant new propagation conditions and
would like to stop the tests, call back the team from the field, and
spend several weeks monitoring frequencies. They would then change
the frequencies of the 20 bands to clear channels and resume testing.
This could take many weeks, since a two month lead time for new crystals
is not unusual.
The change in system performance was so sudden as to cause
suspicion of an equipment malfunction. It was agreed that we would
suspend operation for several days (but leave the team in the field)
while a detailed investigation of the 2DU.would be made. The results
of this investigation will determine the next step.
General System Performance
Because of the interference problem that exists at the base, the
amount of data that has accumulated is very small and its accuracy is
suspect. Much of the data concerns frequencies that are far from the opti-
mum frequency for AS-12 operation, and consequently compilation of this
data could lead to erroneous conclusions about the AS-12. It is,
therefore, imperative that the interference problem be resolved before
further tests resume.
Approved For Release 2001/07/28 : CIA-l DP78-02820A001200060006-6
 Approved For Release 2001/07/28: Cl
EP 66-21f1
iJBJECT: Inspection Report No. 3 - AS-12 with 25X1A5a1
25X1A5a1
Project Status:
1900 -
-+21OO
GMT
1300 -
-130 dbw
1400
"'GMT
-140 dbw
w/10 db pad .7
Some of the data can result in at least relative conclusions.
Consider the period of 13 September to 16 September, daylight hours
at the 500 km range. There were 110 first transmissions within
a sequence. (This is a fairly small sample size, and 500 km is
not a particularly good range; consequently, absolute conclusions
should not be drawn.) Of these transmissions, 35 resulted in con-
firmations at the field set, indicating that the message was received
with less than one percent error rate. As analysis of the data
indicates that if we were to lower the acceptance criteria to three
percent, the number of confirmations would increase to 54. A second
transmission frequently resulted when the first transmission was not
confirmed. Including these and considering the three percent error
rate raises the number of confirmations to 60. Data gathered at the
1000 km range indicates that the confirm to transmission ratio is
higher at the longer range.
iloue
By 8 November - had not yet re-run the acceptance tests on 25X1A5a1
the interference detection receiver. They did, however, vary the
method of establishing the IDU threshold. This threshold is controlled
by a potentioneter located after the last IF. It is adjusted so that
no sounding will occur in a channel with a signal greater than -130 dbw.
(This value is based on the power of the field set. It has been varied at
times during these tests to -125 dbw and. -120 dbw.) This potentioneter
was adjusted to a threshold of -140 dbw and a 10 db attenuator was
placed between the antenna and antenna terminal. The measured probability
of sounding on five bands is given below.
THRESHOLD
BAND 10
BAND 11
B4ND 12
BAND 13
BAND 11
-130 dbw
0 ?
0
0.
0
-58
-140 dbw
w/10 db pad
.26
.06
.97
.01
.85
.01
0
0
.i.6
-54
.2!-
.98
.5
.41
SET.
Approved For Release 2001/07128 : CIAIRDP78-0282OA001200060006-6
 Approved For Release 2001/07/28: CIA-RDP7~-O28{OA001200060006-6
EP 66-241
.000
SUBJECT: Inspection Report No.
25X1A5a1
- AS-12 with
Project Status:
This indicates that the receiver generates much intermodulation
distortion which is no great surprise since it has a 3.5 Me front
end). will perform additional tests to further identify
receiver deficiencies.
25X1A5a1
25X1A5a1
25X1A9a
Distribution:
R&D Subject File
OL/PD/PCB/CAS
R&D Lab
OC-OS
ESB
Monthly (3)
EP Chrono
OC-E/R&D-EP:
9
qS r44