PSC-2 Digital Communications Terminal (DCT)

© Brooke Clarke 2017 - 2022
PSC-2 Digital Communications
          Terminal (DCT)

Background
Description
    Operation
    Cables
    Batteries
Photos
Manuals
Patents
Related
References
Links

Background 

The PSC-2 Digital Communications Terminal (DCT) aka Lightweight Tacfire.  Is very similar to the PSG-2 in functionality.

"The DCT is a rugged, lightweight, microprocessor controlled, handheld message processor. It provides Marine users at all echelons with point-to-point and netted data communications. It is compatible with most MAGTF radio, wire, and encryption equipment. It supports data transfer up to 2.4 kilobits per second in the analog frequency shift keying (FSK) mode and, depending on the transmission media, up to 16 kilobits per second in the digital baseband mode. The DCT allows the operator to enter and read data in both free text and fixed or variable message formats (VMFs). VMF is the tactical message standard adopted by DOD for ground forces. All of the Services have agreed to use this standard."Ch 2 Fire Support Communication Nets, MCWP 3-16 Fire Support Coordination in the Ground Combat Element (Global Security)

Works in conjunction with SINCGARS and other voice frequency radios where it's called a Digital Message Device (DMD).

Description

It turns out that there is no simple provision for external DC power.  It appears that it might be possible using an unkonwn Power Adapter.
It may be the  Litton Data Systems DC/DC Powerstick p/n: 08YX1-417985-101 

Data:
Size: 8.8" x 6.9"
Weight: 5 lbs
Power: 9V, 8 AH Li battery or 28 VDC external adapter
Modulation: Half Duplex digital
Interface: FSK, Digital Baseband and MIL-STD-188C
Xmit Rate: 175, 150, 300, 600, 1200, 2400, 8000, 9600 or 16000 bits per second
Memory: 128 k bytes
Display: 5" x 7" LED dot matrix
Com Protocol: MTS (Marine Tactical System) Broadcast
Physical Interface: MIL-STD-188-114 (Wiki)

Operation

When powered up the screen shows:
>CLOCK  00:00:10 (seconds counting up)
>LOAD FROM PED
>LOAD FROM DCT
>LOAD SPECIAL
>DUMP TO DCT
>DUMP SPECIAL
>SELF TEST
>RUN
   >PURGE
             V4.1
Front Panel buttons: (none of these has any effect, why? let me know)
<- (back space?), Space ->
DIM  BRIGHT (Controls LED display)
MISSION REVIEW, DISPLAY MSG., -ON- Function Select

Cables

W-8 5' DC Power Cable

This is a DC power cable with no data function and it does not mate with the PSC-2.
Littion PN 214552-100
NSN 5995-01-155-7777
contract: N00163-96-C-0164
ASTM D3951-90    12/96

W8  P1,  (Pwr-Adp)

MS 3475 W8-33S
Litton Data Systems, 13973, SOCN, 214552-100,  W8
54462,  1013-W8, Swr No. 3283
W8  P2, (DC Conv-J2)

MS 3475 W8-33P

Fig 1
PSC-2 W-8
                      5' data cable
Fig 2
PSC-2 W-8
                      5' data cable

W-4 Branched Data Cable

This is a "Y" cable for data only, not DC capability. Connects SINCGARS radio to PSC-2.

SINCGARS  PN 214421-100, 1013-W4, NSN 6150-01-155-7961

The cable is labeled:  54462-1013-W4,  Ser No. 2121
The base of the "Y" is labeled W4  P2, (Radio/Comsec)
The branches are labeled:
W4  P1, (DCT)  and W4  P3, (Handset)

Fig 1
PSC-2 W-4
                      Data Cable
Fig 2
PSC-2 W-4
                      Data Cable

CX-13308 PSC-2 DMD to SINCGARS AUD/DATA Cable, 8 foot, NSN : 5995-01-303-0308

looking for it.  Note "TF" refers to Tac Fire or Tactical Fire Control

DC Power Supply PP-8034/PSC-2, NSN 5895-01-146-6739

Have not found yet.

Batteries

Main

The main battery is the BA-5600 LiSO2.
1.5" dia x 7.25" long.  Both contacts on bottom end.  See Fig 12.

Memory & Clock hold up

3.9 Volt AA size but without tit. See Fig 13
Made by Electrochem Ind.
Marked: BCX72(.5g Li) AA -I think the "72" is a typo and should be "27", ie BCX27, TM 08487A-30&P/2 lists A1A2BT1 as Battery, Lithium, Size AA, 3.9 Volts,
Mfr. 62713 (Greatbatch Ltd), p/n: 3BX27XB,
Mfr. 13973 (Litton), p/n: 214477-103

p/ns: 3B27XB, 3B27XF, 3B27-XF, 850546, 6135-01-277-2562, 01-277-2562, 6135012772562, 012772562
NSN: 6135-01-277-2562

A Saft 14500 AA Li-SOCl2 3.6 Volt battery may work.  Have on order.
Battery Space:  LM-ER14505 no tab, Li-SOCl2

Installed the 3.6 Volt 14500 battery on 23 Aug 2022 at 11:46:14.
Now the clock does not reset to zero when the power is turned off or the main battery is removed.
AND the touch screen now works!!!
Note in order to install the 14500 battery the 1.3mm Hex screw in the cap needed to be backed out, the cap installed, then the screw tightened.

Photos

2017 First PSC-2
Fig 1
PSC-2 Digital
                      Communications Terminal (DCT)
Fig 2
PSC-2 Digital
                      Communications Terminal (DCT)
Fig 3
PSC-2 Digital
                      Communications Terminal (DCT)
Fig 4
PSC-2 Digital
                      Communications Terminal (DCT)



2022 Second PSC-2
Fig 10 Screen
PSC-2 Digital Communications Terminal (DCT)
Fig 11 Operating with Sun Shade
PSC-2 Digital Communications Terminal (DCT)
Fig 12 With BA-5600 Battery.
PSC-2 Digital Communications Terminal (DCT)
Fig 13 Note internal DEAD battery.
Many sub-assemblies by 27851 Spectrum Microwave.
PSC-2 Digital Communications Terminal (DCT)



Manuals & Related

AD-A257 457 Naval Postgraduate School, Monterey, California, Thesis, Evaluation of Digital Communications using the Marine Corps Communications Architecture Analysis Model by J.F. Monaghan, Sep 1992

TM 11-7440-281-12&P Operator's and Organizational Maintenance Manual Including Repair Parts and Special Tools List, Digital Message Device AN/PSG-2A (NSN 7025-01-094-5473), May 1982
TB 11-5820-890-10-9 (pdf) Operation of Digital Message Device, AN/PSG-2A with SINCGARS Ground Radio Sets, 1 Apr 1993 - has radio setup, but nothing about PSC-2 operation.
CX-13308 cable to AUDIO/DATA connector on radio.
Switch
ICOM
Radio
Non-ICOM
Radio
Function
SQ On
SQ On
Mode
SC or FH
SC or FH
Data
TF
AD2
COMSEC
CT
(TSEC/KY-57) On CT
*
Off
n/a

PSG-2A
Xmit Block:
Single
Xmit Rate:
1200
Preamble:
0.7

TB 11-5820-890-10-10 (pdf) Operation of Digital Message Device AN/PSG-5 (Fire Support Team) with SINCGARS Ground Radio Set 1 APRIL 1993 - uses CX-13308 cable (the same cable as the PSC-2).

TB 11-5820-890-10-12 Lightweight Tacfire AN/PYC-1 (BCT) and AN/PSC-2 (DCT) with SINCGARS Ground Radio Sets, April 1, 1993
Cable: W32

PSC-2 Lightweight Tacfire
Tone Pair:
1200/2400 Hz
Xmit Block:
Single
Xmit Rate:
1200
Preamble:
0.7 (1.4 or greater when operating with PSG-5)
KY:
Off
Modem:
-18 dBm
TM 9-1220-248-12&P 27 August 1985 Mortar Ballistic Computer, M23 - uses CX-13308 cable (the same cable as the PSC-2).


TM 11-5895-1325-12&P-6-1
TM 11-5895-1325-12&P-7-2-1
TM 11-6625-3132-24
TM 11-6625-3132-40P
TM 11-7440-281-12&P
TM 11-7440-281-30&P
TM 11-7440-326-40
TM 11-7440-326-40P
TM 11-7440-330-40
TM 11-7440-330-40P

TM 11-7440-240-10-1 Fire Direction Center, Artillery, OA-8389/GSG-10(V), )Battalion), NSN 7010-01-017-7039, 1 Feb 1990

FM 6-30 App B, Digital Message Devices (Global Security) - PSG-2A, PSG-5 (TM 11-7025-244-12&P), M23, This section implements STANAG 2934, Chapter 13 Annex A and QSTAG 503.

Patents

Duobinary (Wiki: Bipolar encoding) is mentioned as one of the modulation formats in the pocket manual Vo1 1.

3303284 Framing method and apparatus for duobinary data transmission, Lender Adam, Automatic Electric Laboratories, 1967-02-07, - adds sinewave to the two data streams
3303462 Error detection in duobinary data systems, Jr Berton E Dotter, Automatic Electric Laboratories, 1967-02-07, -
3388330 Partial response multilevel data system, Ernest R Kretzmer, Bell Labs, 1968-06-11, - Prior Art
3993868 Minimum shift keying communication system, Joseph Francis Balcewicz, RCA, 1976-11-23, -- Prior Art - MSK minimizes the bandwidth of the transmitted signal allowing a higher antenna Q, i.e. a more efficient antenna.  This is especially important at frequencies below about 500 kHz.
7072414 Gaussian minimum shift keying (GMSK) precoding communication method, Gee L. Lui, Kuang Tsai, Aerospace Corp, 2006-07-04, - used for deep space coms

Related

Black Message Box - probably a DMD with the same functionality
PSG-9 Message Terminal
Digital Message Device (DMD)
Rugged Handheld Computer (RHC) 31A,  Tactical Terminal (Tacter) 31A
SINCGARS use with PSG-2
CX-13308 SINCGARS to: M23 Mortar Ballistic, PSG-2A, PSG-5, Speaker Extension
Panasonic CF-28, CF-30 Toughbook Laptop computers

References


Links

PRC68, Alphanumeric Index of Web pages, Contact, Products for Sale
Page Created 24 March 2017