PSC-2 Digital Communications Terminal (DCT)
© Brooke Clarke 2017 - 2022
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
Fig 2
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
Fig 2
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
Fig 2
Fig 3
Fig 4
2022 Second PSC-2
Fig 10 Screen
Fig 11 Operating with Sun Shade
Fig 12 With BA-5600 Battery.
Fig 13 Note internal DEAD battery.
Many sub-assemblies by 27851 Spectrum Microwave.
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.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).
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 11-5820-890-10-12 Lightweight Tacfire AN/PYC-1 (BCT) and AN/PSC-2 (DCT) with SINCGARS Ground Radio Sets, April 1, 1993
Cable: W32TM 9-1220-248-12&P 27 August 1985 Mortar Ballistic Computer, M23 - uses CX-13308 cable (the same cable as the PSC-2).
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 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