BROADCAST JAMMING

• Document Type: CREST
• Collection: General CIA Records
• Document Number (FOIA) /ESDN (CREST): CIA-RDP78-04864A000300070002-9
• Release Decision: RIPPUB
• Original Classification: C
• Document Page Count: 2
• Document Creation Date: December 12, 2016
• Document Release Date: March 6, 2002
• Sequence Number: 2
• Publication Date: August 5, 1954
• Content Type: REPORT

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Approved For Release 0669Mk2$NTJi000300070002-9
CLASSIFICATION CONFIDENTIAL
DATE OF INFORMATION 12 July 1954 DATE DISTR.
f1 v G /,74
COUNTRY China
SUBJECT Broadcast Jamming
PLACE ACQUIRED BY SOURCE Okinawa
DATE ACQUIRED BY SOURCE 24 June - 12 July 1954
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SOURCE FBIS-Okinawa
INFORMATION REPORT
25X1A
REPORT NO.
RESPONSIVE
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NO. OF ENCLS.
(LISTED BELOW)
SUPP. TO
REPORT NO.
Observations since 24 June 1954, when the condition was first observed,
indicate that broadcasts of the Chinese International Service beamed to south
and Southeast Asia, and of the Chinese How Service which can be heard in
Taiwan., are receiving intentional interference from transmitters located on
Taiwan, The target areas of the former are Indonesia, Malaya, Indochina,
Thailand, Burma, and India.
The interference observed thus far consists of either a continuous noise-
type jammer or an over modulated transmitter., the latter sometimes broad
enough to cover a width, in kilocycles, five times that of a normally adjusted
broadcast transmitter.
The programs broadcast by these over-modulated transmitters are of one of
five Chinese Nationalist Government Services: "Taiwan Broadcasting Station.,"
controlled by the Broadcasting Corporation of China; "Voice of the Air Force,"
controlled by the Nationalist Air Force; "Voice of the Armed Forces" (BEC22),
controlled by the Ministry of National Defense; "Taiwan Provincial Police Broad-
casting Station," controlled by the Police Department; and the "Cheng Sheng
Broadcasting Station," which is under the control of a broadcasting company
owned by Chang Sheng, who is currently the Vice Premier of the Nationalist
Government.
The Chinese International Service broadcasts on three frequencies of
15083, 116509 and 700 kilocycles from 22s00 to 02000 and from 09230 to 15:30 G61T.
A continuous noise-type Jammer has been observed on 15083 ke/s, while an over-
modulated transmitter is noted transmitting on 11650 kc/s, The transmitter on
Approved For Release 2002/06/28 : CIA-RDP78-04864A000300070002-9
 Approved For Release 2002/06/28 : CIA-RDP78-04864A000300070002-9
CONFIDENTIAL
700 kc/s, which is'located in Kunming in Southern China, is heard without
interference. The programs carried during these periods are in the following
languages: Amoy, Cantonese, Chaochow, and Hakka, intended for Overseas
Chinese; and programs in the national languages directed to Burma, Inaanesja,
Thailand, and Indochina. A half-hour program directed to Japan at 11:00 t
also encounters interference, although a similar program at 21:00 (1T is not
jaused. Noteworthy is the fact that transmissions in English, Korean and
Mongolian in the International Service have not been jammed.
The Chinese Home Service programs, which are broadcast by approximately
20 transmitters from 22:00 to 23:40, from 01:30 to 05:15, and from 09:30 to
15:05 (IT, are treated somewhat differently. No interference has been noticed
as yet on 11000 ke/s, a relay station In Chungking; nor on those transmitters
whose frequencies are not easily heard on Taiwan: 3960, 3915, 1290, and
640 kc/s. Transmitters which normally encounter interference from existing
broadcasting facilities ',A the Far Bast are not molested. They are: 1525t kc/s,
which has interference from a strong transmitter in Karachi, Pakistan during
certain periods; 15130, 15057, 6103, 10400 and 820 kc/s, Frequencies which are
intentionally jammed by an over-modulated transmitter on the same frequency are
11930, 11895, 11830, 10260, 9733, 9063, 9040,7500, and 6200 kc/s.
753.636 193L
CONFIDENPIAL
Approved For Release 2002/06/28 : CIA-RDP78-04864A000300070002-9