spartans_in_darkness

f6ja SEeREli,;'e6MINf"Jj(1
(S//Sf) By the end of 1966, the 3rd RRU was
redesignated the 175th RRC and placed under the
direct control of the ASA command in Vietnam,
the 509th ASA Group. The field station had the
major coverage of the Viet Cong communications
networks in the Saigon and Mekong Delta
regions. By early 1967, the 175th was slated to
move out of the Whitebirch operations area to
Bien Hoa Air Base just outside of Saigon. The
move was accomplished in two steps. Mobile vans
from the AFSS were flown into Bien Hoa and set
up. When they were ready, the personnel packed
up their personal belongings and technical material
into trucks and drove the short distance to the
air base. Within a few hours, the new site was up
and running.
(5//51) With three field sites, the ASA headquarters
in Vietnam had to redefine the areas of
responsibility in the areas of collection management
and mission if the stations were to avoid
inefficient collection and duplicative intercept
and analytic work. In the early 1960s, the station
at Tan Son Nhut in Saigon was responsible for
collection management and reporting for all of
the South Vietnam. However, by late 1966, with
the arrival of numerous DSUs, the situation had
gotten more complex. The support units proved
to be extremely effective at their jobs, but the
overall effort suffered from coverage duplication
and an uncoordinated response to the increasingly
complex VC communications system.!"
(5//51) ASA headquarters assigned the control
of the DSUs to Saigon, but the remote units in
the Central Highlands and near the DMZ were
passed over to the 8th RRFS for supervision. This
proved to be an interim measure. Eventually, the
ASA chose to divide, along geographic regions,
the responsibility for control of tasking and processing
by the DSUs to the 8th RRFS and two
ASA battalions, the 303rd ASA Battalion at Long
Binh, and the 313th ASA Battalion at Nha Trang.
All collection, processing, and reporting efforts at
all of the DSUs and stations were now coordinated
through the three management authorities. By
1967, the system was further refined when the
1\'\10 ASA battalions ceded SIGINT operations to
their subordinate companies while retaining the
administrative functions.
(S//Sf) Phu Bai was responsible for communist
communications near the DMZ, the two
provinces south of it (Thua Thien and Quang Tri),
and all of Hanoi's military communications with
its major commands in the South. The 303rd ASA
Battalion handled all communist communications
in the provinces around Saigon south into
the Mekong Delta - equivalent to the VC military
regions VI through IX. The 313th at Nha Trang
was responsible for all communist activity in the
Central Highlands from Quang Nam province
south to Dar Lac.
(Sf/51) The major reason for all of these reorganizations
was the arrival of the numerous ASA
DSUs from 1965 through 1967. These support
units were configured to optimize the collection
of tactical voice communications. The basic unit
was a company which supported an army division.
Detachments would be formed from the
company to support the brigades or regiments of
a division. Independent army brigades carried
their own ASA detachments, such as the 404th
RR Detachment which was attached to the 173rd
Airborne Brigade.
(£//51) Each company carried a complement
of five vehicle-mounted mobile intercept positions,
known as a MRPV, and five man-pack voice
intercept equipments, known as a RTPV. Each
MRPV consisted of two HF/VHF intercept positions,
with a R-392 (HF) and R-744 (VHF)
receivers, and a PRD-1 SRDF equipment. These
companies could break down further to form
detachments which consisted of three MRPVs
and three RTPVs. Because of the predominance
of communist HF manual morse communications,
and the concurrent scarcity of voice communications,
the companies removed two HF
positions from the mobile elements and created a
TQP 6ESRET,'{SOMIN"FNJE1 Page 289