A CRYSTADYNE (CRYSTAL SET) ATTACHMENT

• Document Type: CREST
• Collection: General CIA Records
• Document Number (FOIA) /ESDN (CREST): CIA-RDP80-00809A000600300320-2
• Release Decision: RIPPUB
• Original Classification: C
• Document Page Count: 2
• Document Creation Date: December 22, 2016
• Document Release Date: September 7, 2011
• Sequence Number: 320
• Publication Date: April 21, 1950
• Content Type: REPORT

Sanitized Copy Approved for Release 2011/09/08: CIA-RDP80-00809A000600300320-2 ?
CLASSIFICATION CONFIDENTIA> QNFI ~ ~~`+L
CENTRAL INTELLIGENCE AGENCY REPORT
INFORMATION FROM
FOREIGN DOCUMENTS OR RADIO BROADCASTS CD NO.
COUNTRY
SUBJECT
HOW
PUBLISHED
WHERE
PUBLISHED
DATE
PUBLISHED
LANGUAGE
Scaentific - Radio
Monthly periodical
Moscow
TN' DOCININT CONTAINS OI/ONNATION AIRCTINI TNI NATIONAL 51711111
OF Tx1 ONR10 ITlv1 N17011 1x1 NIANINI 01 tOIONU[ ACT Io
I. I. C.. NI ASS 01.111111510. 111 T.A..NI11ION ON TNA SINIIATION
NI I N CIITANT. IN ANT NANN.N TO AN uNAN olINO ntlTN IS I,? TNo
ISITAP S/ LAt. S1ISOOVMON 01 TNII /OSIT IS
rNONIS111 O.
DATE OF
INFORMATION 1949
DATE DISTP Apr 1950
NO. OF PAGES 2
SUPPLEMENT TO
REPORT NO.
THIS IS UNEVALUATED INFORMATION
A CRYSTADYNE (CRYSTAL SET) ATTACHMENT
Amateurs possessing crystal sets can increase the range and volume of recep-
tion by adding an amplifier with an oscillating crystal (crystadyne) to their re-
ceiver.
An amplifier of this type does not require radio tubes or high-voltage batter-
ies and is simple to make. The only difficulty may be in obtaining the ziucite
crystal (zinc oxide), which is rarely seen on sale. An amplifier of this type does
not work so well with other crystals.
The amplifier can be made as a separate attachment mounted in a 100 x 80 x 50
millimeter box. Two small pocket-flashlight batteries connected in series are
placed inside the box. The crystal holder must be cushioned by setting it on a
rubber sheet or by suspending it on springs. /See appended circuit diagram/
The crystal for this attachment can be of the usual construction. The impor-
tant point is that it be tuned conveniently (to select a sensitive point) and that
the pressure of the spring on the crystal be adjustable. A steel spiral of 0.15-
millimeter wire with a pointed end will serve the purpose and can be made from a
field telephone cable.
To obtain greater volume it is desirable to use an external antenna about 4,0
to 50 meters long. It is also possible to use the lighting network as an antenna
by connecting one of the wires through a mica condenser of about 500 microfarads
to the antenna terminal of the -rystal set. In the latter case, it is necessary
to avoid switching the receiver on and off the network too frequently since the
current shocks thus produced will damage the crystals of both the receiver and the
attachment.
The attachment is not difficult to operate. Having switched on the receiver,
one finds a sensitive point on its crystal (if the receiver crystal has a fixed
point, it is necessary to adjust only the attachment crystal). To find the
STATE
ARMY
CLASSIFICATION CON#TBl~1PIAL
NA`.H NSRB ql IBUTION
AIR X FBI
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RETURN TO AGENCY ARCHIVES
Sanitized Copy Approved for Release 2011/09/08: CIA-RDP80-00809A000600300320-2
 Sanitized Copy Approved for Release 2011/09/08: CIA-RDP80-00809A000600300320-2
ti
CCIFIDENTIAL i, Gu~~1S
oscillating point on the zincite crystal, the variable resistor R1 is cut out com-
pletely, i.e., full voltage is applied to the crystal. When a loud rushing noise,
or whistling in the case of a local radio station, is evident, it can be assumed
that the oscillating point has been found. Then it is necessary to gradually in-
sert the variable resistor R1 into the circuit until the purest and loudest trans-
mission is obtained. If this does not give adequate volume, it is necessary to
find a new oscillating point which will give good amplification.
The receiver and attachment should be tuned at the same time. If, during this
time, oscillations cease, the pressure on the _spir_i . ing
zhould be with-
out shifting it to a new place on the crystal. Usually, this resores the oscilla-
tions. Sometimes oscillations will not start again due to the excessive voltage on
the crystal. In this case, the voltage should be lowered through R1 while search-
ing for a new point. A change-over switch may be included to make possible a com-
parison of the receiver performance with and without the attachment.
ZD-iagram follows.]
Zincite
R2 . 800-1000 ohms
R1 . 8-10,000 ohms
E . 8-12 volts (1-4 ma)
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Sanitized Copy Approved for Release 2011/09/08: CIA-RDP80-00809A000600300320-2