DEVELOPMENT OF A MICRO-MINIATURE RECEIVER

• Document Type: CREST
• Collection: General CIA Records
• Document Number (FOIA) /ESDN (CREST): CIA-RDP78-03424A000800010006-8
• Release Decision: RIPPUB
• Original Classification: C
• Document Page Count: 8
• Document Creation Date: December 22, 2016
• Document Release Date: February 8, 2012
• Sequence Number: 6
• Content Type: MISC

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Declassified in Part - Sanitized Copy Approved for Release 2012/02/08: CIA-RDP78-03424A000800010006-8
DOC ~ REV DATE IO Ar*~n BY ~ 73
ORIG COMP ~3 _ OPI _J _ - TYPE _~~ .~
ORIG CLASS ~ FaGES ~ R?Y GEaSS C--
JUST ~ NEXT REY~L--~ AUTHs HR lil?2
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This proposal. briefly outlines the objectives of a development program
which would. be undertaken by the
The overall. objective of the program would be the de-
velopment of a micro-miniature solid-state receiver. The proposed oper-
ating characte.rist:ics of the receiver, as indicated i.n Secti.on 3 of this
proposal, a:re tentative and may be mod.i.fied or expanded as required by
the customer.
Sect.i.on 2 of this proposal briefly outlines the objectives and ac-
complishments of the micro-miniature program currently in progress at t:b.e
Section 3 includes a description of 'the three
units which make up the complete receiver system. The first unit is a
plug-in assembly consisting of a tuned RF stage, crystal controlled local.
oscillator and mixer. The second. unit incorporates the IF stages, a
detector, beat frequency osci.l.lator and audio amplifier. The last un:i.t
is a plug-in selective call circuit designed to meet specifications similar
to those used for the development of the unit which was delivered. in the
latter part of 1.958
Throughout the development program, effort wil.1. be directed towards
the use of the latest circuit techniques and components consistent with
.reliable operation of the receiver.
BY
TYPE
AUTHt HR 10-Z
25X1
25X1
Declassified in Part - Sanitized Copy Approved for Release 2012/02/08: CIA-RDP78-03424A000800010006-8
 Declassified in Part - Sanitized Copy Approved for Release 2012/02/08: CIA-RDP78-03424A000800010006-8
2.0 MICRO-COMPONENT TECHNIQUES
have been pursuing a joint program in the
field of Solid State Microelectronics. The approach taken has been both
practical and versatile.. The essential form factor is two-dimensional.
leading to the generic designation thin circuits.
The thin circuit approach involves the utilization of a thin insu-
lating substrate upon which the circuit is fabricated. Some elements are
formed directly on the substrate by vacuum deposition or other means;
these include such passive elements as resistors and capacitors as well
as conducting runs for interconnections. Additional elements are packaged
separately and subsequently incorporated in the circuit; these include
active and passive elements such as micro-transistors micro-diodes,
micro-tunnel diodes, some capacitors and inductors. This fabrication
philosophy allows pre-selection of critical components of demonstrated
ability and reliability.
The result of this program has been the development of the equipment
and techniques necessary for the fabrication of the micro-components.
Transistors diodes and reference diodes have been packaged in small
pillbox enclosures. The dimensions of these enclosures are 50 mils
diameters 15 to 25 mils high. Since tunnel diodes are much less affected
by surface conditions than any other semiconductor devices they do not
require a hermetic package for most applications. Peak currents for the
tunnel diodes can be obtained in the 1 to 10 ma range with a tolerance of
5~ or better.
Thin film resistors using a nickel chromium alloy have been deposited
by evaporation techniques. This alloy has a relatively high resistivity
and enjoys a low temperature coefficient of resistivity. Furthermore,
when properly processed, it is stable against aging. The lower practical
limit of film resistance that has been reached is approximately 20 ohms
per square. The upper practical limit is about 250 ohms per square which
means that a 25,000-ohm resistor can be made by using a film strip 10 mils
wide and one inch long.
Declassified in Part - Sanitized Copy Approved for Release 2012/02/08: CIA-RDP78-03424A000800010006-8
 Declassified in Part - Sanitized Copy Approved for Release 2012/02/08: CIA-RDP78-03424A000800010006-8
Thin film capacitors have been fabricated using various dielectric
materials such as silicon monoxide and anodized tantalum. Capacitors in
the range from 20,000 to 80,000 ??f per square inch have been made with
dissipation factors less than 2~ at 10 mc.
Typical micro-miniature circuits fabricated anal evaluated during the
present effort are illustrated in Figures 1 and 2. Figure 1 shows arrays
of micro tunnel diodes in resistance-coupled shift register circuits.
One of the circuits shown is a three-phase, three-stage shift register
with nine tunnel diodes and 18 evaporated resistors. The other circuit
is a shift register stage on a Signal Corps Micro-Module wafer, containing
three tunnel diodes and seven evaporated resistors.
Figure 2 is a double NOR circuit containing four evaporated resistors,
two titanate wafer capacitors, two transistors, two voltage reference
diodes, and four diodes. The two transistors are located at center-top;
the four diodes; upper right and left side; and the two reference diodes,
right and left center.
. Declassified in Part - Sanitized Copy Approved for Release 2012/02/08: CIA-RDP78-03424A000800010006-8
 ~ ~_
Declassified in Part -Sanitized Copy Approved for Release 2012/02/08 :CIA-RDP78-03424A000800010006-8
(a) .One-stage Tunnel Diod.e.Shift Register. on Signal
Corp wafe"r (3 diodesy 7 res3.ators)
(b) .Three-stage Tunnel Diode .Shift Regl.ster
(3 .Diodes .and 6.resistors per stage)
Figure 1. Micro `Funnel Diod.e~ Shift Registers
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 Declassified in Part -Sanitized Copy Approved for Release 2012/02/08 :CIA-RDP78-03424A000800010006-8
(a) One-stages ~u~,nel T3iod.e Shift Regi~f,;~r on 8i.gca.al
Corp wafer (~ ~3S:c>c]~sg '~ resistors)
(~) ~rhrE~~stage ~-~~n~~ n~~~~ sr~.ft ~~g~~~~~
(3 triodes aa~.d 6 resistors per stag)
~'i.gure 1. :~Iir.ro ':ica:nn~1 pidd.e 5~+~,ft ~egi.sters
Declassified in Part -Sanitized Copy Approved for Release 2012/02/08 :CIA-RDP78-03424A000800010006-8
 Declassified in Part - Sanitized Copy Approved for Release 2012/02/08: CIA-RDP78-03424A000800010006-8
Figure 3 indicates the block diagram of the proposed micro-miniature
receiver. The tentative characteristics of the three units are described
in the following sections.
3.1 RF Circuitry (Unit No. 1)
Unit No. 1 will consist of an RF stage, a crystal controlled local
oscillator, and a mixer. The RF stage will provide amplification as well
as frequency selectivity necessary with particular emphasis on image
rejection. The crystal controlled local oscillator will provide the re-
quired signal to the mixer so that the output frequency of the unit will
be at 455 kc.
These fixed tuned units will be of the plug-in type. In this way
various plug-in units may be interchanged and thus provide for reception
at discrete frequencies over the range from 3 to 30 mc.
In the development of unit No. 1 considerable emphasis will be
placed on the possibility of utilizing tunnel diodes as the active elements.
The operating characteristics of these devices indicate the possibility
of improved performance combined with circuit simplicity when compared with
conventional transistor circuitry. This is particularly important when
micro-electronic circuitry is considered.
It is anticipated that the maximum overall volume of this plug-in
circuit will be in the order of 0.5 cubic inches.
3.2 Main Receiver Unit (Unit No. 2)
Unit No. 2 will consist of the IF stages (probably three), the
detector, the beat frequency oscillator, and an audio amplifier.
The three-stage IF amplifier will make use of the barium titanate
transformers which have been developed during previous programs. These
devices provide the required impedance matching and frequency selectivity
in a minimum amount of space. The IF amplifier will be fixed tuned at a
frequency of 455 kc. The detector will utilize a micro-diode i.n con-
junction with the beat frequency oscillator to provide an audio tone
on CW transmissions.
Declassified in Part - Sanitized Copy Approved for Release 2012/02/08: CIA-RDP78-03424A000800010006-8
 Declassified in Part - Sanitized Copy Approved for Release 2012/02/08: CIA-RDP78-03424A000800010006-8
O
RF STAGE
LOCAL OSCILLATOR
MIXER
HEADPHONES
IF AMPLIFIER
DE'ITECTOR
BEAT FREQUENCY OSCIL-
LATOR
? AUDIO AMPLIFIER
(Plug In)
SELECTIVE
CALL
CIRCUITRY
(Plug In)
Figure 3. Block Diagram of the Proposed Micro-Miniature Receiver
The latest circuit techniques and devices will be examined in the
course of the design in order to optimize reliability, receiver performance,
and minimize physical size. In particular, the possible use of a tunnel
diode as the BFO will be carefully studied.
It is anticipated that unit No. 2 will occupy a maximum overall
volume of 0.5 cubic inches. Thus units 1 and 2, which comprise a complete
fixed tuned receiver will occupy a total volume of less than 1.0 cubic
inch. The exact form factor that this volume will occupy is open to final.
determination by the customer.
3.3 Selective Call Circuitry (Unit No. 3)
The selective call. unit will be of the plug-in type and may be sub-
stituted for the earphones in the jack of unit No. 2. The operating
characteristics of this unit will be similar to those of the selective
call unit already delivered to the customer. It will provide for the
alerting of a single station out of approximately one thousand receivers.
Declassified in Part - Sanitized Copy Approved for Release 2012/02/08: CIA-RDP78-03424A000800010006-8
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Declassified in Part - Sanitized Copy Approved for Release 2012/02/08: CIA-RDP78-03424A000800010006-8
This selection will be made by the transmission of a particular code
which corresponds with a code previously set into the receiver,
Briefly when a code group is received it is compared, bit by bit
with a code previously set in the selective call unit. If both codes are
the same a signal is passed to the alarm circuit Any difference will
cause the message to be rejected and the alarm circuit will not be
allowed to function.
A plug-i.n selective call unit of this type will occupy a maximum
volume of approximately one cubic inch.
~ Declassified in Part - Sanitized Copy Approved for Release 2012/02/08: CIA-RDP78-03424A000800010006-8