Trimble Trimpack Family of GPS receivers

Trimpack SLGR AN/PSN-10 "Slugger" L1 3 Channel 
Tanspak L1 3 Channel  
TransPak II L1 6 Channel  
L2 P-Code & SAGR   

Antennas  
Back Up Battery
Computer I/O  
Mounting  
Power Sources 

Background

I have seen Trimpack, Trimpac, Trimpak, Transpack,  Transpac and Transpak, Spartan.  Don't know why all the different names.  I've tried to seperate some of these based on some manuals but if you know more about the names please let me know.

The first generation of GPS receivers used conventional receiver design.  The second generation used a Digital Signal Processing (DSP) chip or a custom DSP chip and processed only a small number of channels (4 is the minimum number of satellites needed for a fix, but a receiver with fewer than 4 channels can be used by time sharing one or more channels.).  The first Trimpack type GPS receiver was only a 2 channel unit.  Later models were 3 channel and the last in the series were 6 channels where 4 channels were always tracking the best 4 satellites and the other 2 channels were searching for better satellites.

Modern (2003) GPS receivers are 12 channel designs and can track all the satellites in view.  This has a big advantage because the receiver does not need to drop one satellite to acquire another.  Since there are 24 satellites in orbits that are relativity close the the Earth, only about half of them can be seem at one time so 12 channels is an optimum number for a GPS only receiver.  If the receiver can also track other navigation system then more channels are a good thing.

There are a number of Differential correction transmitters operating in the 283.5 - 325 kHz Low Frequency band and when their data is fed into a GPS receiver it's accuracy is improved.  There's also a WAAS system using geostationary satellites to send the same type differential correction information, but the satellites have much wider coverage than the local DGPS transmitters.  The Trimpack receivers that have a Computer I/O connector can take advantage of the LF DGPS signals by means of a seperate LF receiver, but can not use the WAAS signals because to do that requires a fundamental change to the signal correlator.

Selective Availability

GPS was designed so that military users, who have receivers that can receive both the L1 and L2 frequencies and who have the required cryptographic keys, can get much more accurate results than the civilian L1 only receivers.  Once there were enough satellites operational it was discovered that the L1 only receivers worked better than the system designers thought they would so Selective Availability was implemented to degrade the accuracy of civilian L1 only receivers for positioning applications.  This was done by dithering the clock and maybe by changing the navigation data.  SA did not degrade the results from the military Precision Positioning Service (PPS), only for the civilian Standard Positioning Service (SPS).  On May 2, 2000 SA was turned off, they say permanently.

When SA was on there was typically one satellite that did not have SA turned on.  This could be used for precision timing in a position fixed mode where only one satellite is needed for timing.

During the gulf war the SLGR, L1 only receivers were needed in the desert and so SA was turned off.  Prior to 2 May, 2000 there were other occasions SA was turned off like to search for a downed plane and the CAP was using civilian GPS receivers.

Note that now, with SA turned off, all the Trimpack receivers seem to get within 0.1 arc seconds ( about 10 feet) very quickly after a warm start.  Using just the civilian L1 C/A code.

The Magellan GPS NAV 1000M was also used in the first desert war.

Operation

These receivers were intended for use in battery powered man carry applications or mounted in a ground, air or water vehicle using a battery pack or a common 12 or 24 Volt vehicle power supply.

Front Panel

LCD

The Front Panel has a 4 row by 20 column LCD that is backlight (off, 1, 2,3 intensity settings).  The LCD is of the type that is best viewed from straight on.  If the Trimpack is hung around your neck using a camera type strap then when you look into the LCD, it will have good contrast.  When the vehicle mount is used you also look straight into the display.  The PLGR display is designed for 6 o'clock viewing (from below straight on, and so is impossible to view from above, like when it's in a vehicle mount that's below eye level.

Switches

To the right of the LCD is an 8 position Function switch and to the upper right of that there is a 2-way momentary switch that works left-right, L-<center<-R.  Below this switch is another like switch that operated in the Up/Down axis marked INC -<center> DEC.

By using the Function switch to select the overall function and then the INC/DEC switch to get to the sub menu, then the L/R switch to get to an item, then the INC/DEC switch to change the item, then the INC/DEC switch to move to a new item a lot of parameters can be seen or set.  Although the forgoing description seems long, the menu navigation is very intuitive, but it can be tedious.

Latitude and Longitude Display

The display of Lon. and Lat. is to 0.1 seconds.  One second of Latitude corresponds to about 100.338541 feet anywhere on a spherical Earth.  One second of Longitude depends on where you are ,COS(Lat), at the Equator is the same as for Latitude and at the poles it's 0.  For my Latitude it's 78.5416666 feet. So a tenth of an arc second is about 10 feet N-S and about 7.8 feet E-W for me.  Placing the Trimpack on known objects and allowing 400+ averages (400 seconds) results in errors of about 40 feet in all three dimensions (2003 i.e. SA is off).

The Altitude displays to 1 Foot.  Note that 0.1" of Lat or Lon is about 10' or 7.8' and so is about 10 times more coarse than the altitude reading step of 1 foot.

When averaging, within about a day the Lon and Lat were reading the correct value to the 0.1 arc second level, which is as precise as this unit can display, but the altitude took a few days to settle down to +/- a couple of feet.  The averaging counter seems to count up to maybe 32, 000 and something, then count down, and up, etc. with strange characters being displayed.  For example now it's counting down and just rolled over from -Exxx to -D999.

The 14992-20 is connected to the 28367-49 mag mount antenna which is on the rain gutter.  It's average altitude is 891 and the mast mounted antenna feeding the AN/PSN-10 is reading about 900.  The 9 foot separation may be reasonable.  It takes about 2 days of continous averaging to get the elevation to 902 +/- 1 foot.  But it only takes maybe an hour to get the Lat and Lon to stablize to within 0.1".

Trimpack SLGR AN/PSN-10 "Slugger" L1 3 Channel

The Left side of the 16768-20 AN/PSN-10 has the External Power connector at the rear and the Computer I/O connector just behind the External Antenna jack.  The other views are the same as for the 14992-20 except the color is green instead of black. The backlight in the 16768-20 is white, not red like in the 1499-20.

Small Lightweight GPS Receiver only SPS capability, Operation Desert Shield used 8,000. This is the Trimble Trimpack   Note that this receiver is not capable of receiving the Presicion Positioning Service on the L2 frequency using the P-code.  It can only receive the Standard Positioning Service on the L1 frequency.  That's why is does NOT have a key load connector.

During the Gulf war (Desert Storm, Desert Shield) SA was turned off so these receivers would provide good accuracy.

Part Number Table

Description	# Chan	Color	Trimble p/n	NSN	Con1	FW	Comment
SLGR- Trimpack	2 L1		12545-00	5825-01-356-7849	A P I	1.08a	Not very good performance with only 2 channels
SLGR- Trimpack	3 L1	Green	16768-002	5825-01-357-5506	A P I
SLGR-Trimpack	3 L1	Green	16768-102	5825-01-357-6171	A P I	2.02a	Have Quick 1 PPS output F04701-890C-0087
SLGR-Trimpack	3 L1	Green	16768-202	5825-01-357-6170	A P I	2.02a 2.05a 2.05c	Have Quick
SLGR-Trimpack	3 L1		16768-30		A P I
SLGR- TGPS II	3 L1	Green Black Knob	16768-66		A P I	2.07	Have Quick more than 26 WP, maybe not 1089
		Green	16768-80			1.15	8/11/1992
Pathfinder Basic+	6 L1		16787-20	n/a	A, ?		" GIS mapping

^{1 Connectors A = Antenna, P = Power, K = Key Load, I = I/O
2}There were  a number of optional firmware versions of the 16768 that had various way point capacities or Have Quick 1 PPS outputs.

Documents

Title	p/n	Applies to
Ref Man	13498	12545-00
Ref Man	13498	16768-00 (Red Screen)
Ref Man	13498 A-D	16768-10 (Have Quick, Green scrn)
Ref Man	13498	16768-20 (Green screen)
Ref Man	13498 A-E	16768-30 (1089 WPTs)

Firmware

The firmware in this receiver (V 2.02a) is identical to the to the firmware in the 14992-20 Trimpack.  The Function switch has the same labels on each position and the menus are the same as the 14992-20.  The firmware is contained in 4 each 28 pin chips (probably ROMs or EPROMS, but not EEPROMs) but they are in sockets that have 32 pins so maybe larger firmware programs can be retrofitted or are used in other versions, maybe like the Centurion.  The existing 28 pin chips might be the 27256 EPROM, 256k bits, 32k Bytes per chip.

If you have a Trimpack please let me know the part number and firmware version of your receiver.

Computer I/O

The STS manu page has these 3 choices for Computer I/O:

• Trimpack - This is the standard I/O protocol
• Track-2 - This allows data logging and post processing, maybe carrier phase?
• OFF -

Using a Passive cable between the RS-422 output of the AN/PSN-10 and my decktop DB-9 RS-232, with the AN/PSN-10 set for:
Data Port -- TRIMPACK  The following binary data packets are being sent:
41 GPS Time
42 Single-precision Position Fix XYZ ECEF (every second)
43 Velocity Fix, XYZ ECEF (every second)
44 Satellite Selection
46 Health of TRIMPACK
49 Almanac Health Page (when received from sat)
4B Machine/Code ID & Additional Status
5B Satellite Epherimis Status (when new sat is acquired)

The AN/PSN-10 will track satellites when inside a two story house, but nowhere as many as It will track outside on a hill.

Tanspak L1 3 Channel

The Transpak receivers seem to be based on the AN/PSN-10 except the External DC power connector and the Computer I/O connector are not used.  You can see the places on the case where these connectors would be.  Inside the printed circuit boards appear to be the same as for an AN/PSN-10, but have missing parts, probably related to the missing connectors.  The firmware appears to be identical to the AN/PSN-10.

There's a place for a connector in the lower left corner and a second one just to the left of the Antenna connector.

Description	# Chan	Color	Trimble p/n	NSN	Con1	FW	Comment
TransPak	3 L1	Black	14992-00		A	2.05	9MAY1989
TransPak	3 L1	Black	14992-20	5825-01-364-6283	A	2.02b
TransPak	3 L1	?	14992-30	?	?	4.2

Function Switch & Menus

^Z There is a symbol preceding the h:mm Battery used number.  I have seen @, ?, >, = and ;  What do these mean?
The Trimpack uses an internal battery to keep all the data in RAM when the battery is removed or when the receiver is off.  This may have been done because the battery life is only about 10 hours.

If the receiver is turned from OFF to FIX, the receiver will be on long enough to get a fix and then the top line will change from the DOW and time to a message counting down from 30 seconds and  the receiver will turn off.  This provides a fix with the minimum drain on the battery.

If averaging is turned on it will not average unless the receiver is actively tracking 4 or more sats.  The POS display shows the averaging count in the lower right corner as (nnnnn).  When the receiver is turned off it automatically sets averaging to off.

Status screen #2 Data Port is interesting since the 14992-20 does not have a data port.  I expect the there are a number of different versions of the Trimpack made by stuffing the boards differently and using different jumpers to tell a common firmware which options are enabled. 

It may be possible to add the two U-229 type connectors to the left side of this receiver and have external power and computer interface.

14992-20 Current Consumption
 

Battery Volts	Current  ma	Power Watts
7.7	293	2.26
8	280	2.24
9	340	3.06
10	300	3.0
11	270	2.97
12	250	3.0
13	231	3.0
14	222	3.33
15	215	3.26
16	208	3.32
17	205	3.49
18	200	3.6
21	200	4.2
24	200	4.8

Disassembly

Remove 13 each screws with a 5/64" hex driver that are around the diagonal part line. and wiggle carefully apart since there is a 2x8 pin header connecting the two halves.  I have heard that some receivers have a ribbon or flex cable making the connection.

Construction

One part is the bottom back.  It has the battery connection and inside a switching power supply.  The Front Top contains the control panel and built-in antenna and one the sides any I/O connectors that may be needed.

Both the power supply and the top Printed Circuit Boards in the 14992-20 have a number of parts that are not installed.  This is a common practice where a manufacturer builds a single design for the PCB and stuffs the board different ways to make different models.

Power Supply Board

 Is a switching mode power supply.  Heat sink to bottom of case. Provides 5.0 VDC to power receiver.

Parts

U1 - MC33063 - Switching Mode Power Supply controller. There are maybe a couple of dozen parts surrounding this chip resistors, caps, diodes and transistors.  Looks like an expensive SMPS.
U2 -Philips HEF4011BT - CMOS positive quadruple 2 input NAND
U3 - Motorola 14013B - CMOS Dual type-D flip-flop
U4 - 14 pin IC not installed.  What's it for?
Q2 - not installed and a jumper is there, maybe emitter to base?

Connectors

J1 - 1x5 header - has jumper on pins 4 & 5. right next to a place where a J-229 type 5 pin connector could be installed on outer case.  This is where the External Power connector is installed.  When the Trimpack has the external power connector and is running on batteries a special "shroting cap" is needed that does the same job as the jumper on the header pins 4 & 5.

Pin	Function	Note
A	Internal Batt Neg	Do not use
B	External Ground
C	Internal Ground	Do not use
D	External Power	+9 to +32 Volts
E	Internal Battery Negative	Do not use

J2- 2x8 header that connects to J41 on the digital board
J3 - Screw connecting to the battery negative terminal
J4 - Screw connecting to the battery positive terminal

Digital Board

The CPU is a Motorola MC68HC000.  There are only two static RAM chips installed, but it looks like you could have 8 installed.  This might be used for increasing the number of way points.

Remove 8 each Philips #1 screws to free board. Carfully lift it up off the the two headers that connect it to the analog board below.

Parts

U1 - MC68HC000FN10 32 bit CPU the 10 suffix may mean a 10 MHz clock rate
U5 & U9 - HM62256LFP-10 Hitachi 32 k x 8 bit Static RAM chips, the -10 may mean 100 ns access time
U2, U3, U4, U6, U7 & U8 - pads for more RAM chips Maybe JU1, JU2, JU3 & JU4 are related to the RAM option?
U10, U11, U12, U13 appear to the the ROM or EPROM chips with the code for the 68000 CPU.  They are 28 pin chips, but are in 32 pin sockets.  p/n 17246-01, -02, -03 and -04
U15 - DS1231-20 - Low Battery Voltage detector
U16 - DS1221S - Converts CMOS RAMS into nonviotale memories, pins 13, 12, 11 & 10 go the Chip Endable on the RAM chips.
U17- TNL 13816 - probably Trimble custom gate array IC
U18 is not installed and is probably for the P code processor chip.
U20 - OKI M6242B - real time clock with date, time and alarm functions
BAT1 - Tadiran TL-5104 3.6 Volt AA size with wire leads

Connectors

J3 - 2x20 header socket connects the the analog board.  Pins 17 & 19 are one polarity power from J41 and 18 & 20 the other polarity from J41
P2 - 2x4 header socket connecting to the analog board. Physically close to the CPU and connected to it.
J41 - 2x8 header socket connecting t the power supply board

Analog Board

Under the top digital board with the CPU and related circuitry is what appears to be an analog/RF board that has a couple of daughter boards and these have granddaughter boards.  U8 and a number of parts on this board are not installed, maybe for L2 processing. 

Remove 8 each hex spacers with 3/16" nut driver.  Lift up to disconnect the 2x12 header connecting to the panel PCB.  Unplug the INT and EXT coax antenna cables.

Parts

CR5 - LM335 - analog output Precision Temperature Sensor. Feeds U5 A/D converter
Q5 - 2N2907 near the EXT antenna connector, maybe related to sensing or powering the external antenna.
U1 & U2 -not installed 16 pin surface mount parts. very close to J3 connecting to the front panel.
U4 - 74HC574 - Dual type-D Flip-Flop
U3 - XR88C681CJ - Dual UART - This may be to communicate with the panel and/or for external computer I/O?
U5 - ADC0808FN - 8 channel MUX + 8 bit Analog to DIgital converter.  100 microsecond conversion time, easy interface to 8 bit micro controllers.

• Synthizer operation
• IF module
• Antenna Power Supply Feeds
• Internal Temperature
• Display Temperature
  

U6 - SA5230 - low voltage op amp on the INT antenna side.
U7 - TI026B - ? part of the EXT antenna circuitry
U8 - Not Installed 44 pin IC
U11 -74HC04 - High speed CMOS Hex Inverter part of the EXT antenna circuitry
Y1 - NDK 16.368 MHz oscillator in a can. J7 is what looks like the hold pattern for an SMA or OCX jack maybe to measure the oscillator output. Or maybe to be used for an optional larger oscillator.  Probably the clock for the 68HC000.

Connectors

P1 - Not installed, 9 pin header with pin #4 not used, polarize the connector, Near uninstalled U8
J1 - 2x20 header connection to J3 on digital board
J2 - 2x4 header mates to P2 on digital board (P2 is near the 68HC000)
J3 - 2x12 header socket connects to panel P3 header
J4 - 1x6 header with pin #2 removed.  right next to U8 which is missing on the 14992-20. maybe goes to the key load connector when it's used.

Function

The INT and EXT antenna inputs seem to both be combined rather than switched and go to FL1, a bandpass filter.  From there to U10 maybe a MMIC amplifier then to a daughter board made from microwave quality double sided PCB material that appears to have a 3 dB coupler, a couple of transistors and biasing circuitry. Maybe an L1 - L2 frequency separation point. On either side of the coupler daughter board there are two more daughter boards. 

The TNL16239 PCB has a metal shield can over some hidden circuitry and a Murata mixer. 

The other daughter board has a lot of ground plane on one side and an LT1016 Ultra fast precision 10 ns comparator, SA604AS low power 45 MHz F0, 25 MHz BW FM IF, and LM2904 dual op amp.

Panel Board

Behind the panel is another board to support the panel functions.

Parts

U1, U3, U3, U4  - OKI M5839B - maybe LCD related memory?
U5 - HD44780 - the standard LCD controller chip
U6 - LM2904M -low power dual op amp - Probably related to the display temperature measurement that different from the internal temperature measurement.

Connectors

P3 2x12 header connects to analog board J3 socket.  This is a right angle header, so you can not remove the panel without first removing the analog board.

There are 5 holes in line, like would be used for a 5 pin header next to the panel switches L, R, INC, DEC, maybe for testing them?

Startup

After separating all the boards for the photos and changing the UTC offset to LOC=UTC-7 for California and Daylight savings time, it took about 1 hour and 8 minutes of " Tracking  0 SV's" until it started tracking again.

I have seen the # of SV's go up to 8 outside in the open.  After the receiver has sat in the same position for awhile and is tracking well, if it is moved, even a few feet it seems to sense the change and the # of SV.s drops and then in time comes back.  So I'm going to try again to get the EXT antenna connection to work by leaving the receiver in EXT ant mode for a few hours.

TransPak II L1 6 Channel

This appears to be newer than any of the above receivers in that it is a 6 channel, rather than a 3 channel receiver.  The 19437-60 appears to be a civilian receiver based on the use of a plastic Conxall connector for the Computer I/O instead of the military U-229 type connector.

19437-60 Specific

Part Number Table

Description	# Chan	Color	Trimble p/n	NSN	Con1	FW	Comment
TransPak II	6 L1	Black Org ltr	19437-60	n.a.	A X	4.10	This is a civilian GPS receiver.
Pathfinder	6 L1	Black	14992-60				Comes in suitcase with ext antenna, yellow bag
TransPak II	6 L1	Black Org ltr	14992-70		A, I	4.10	Front, Left Side
Op & Maint manual	na	na	18090 Rev C				6.5 x 4.5" 75 pages, June 1992
Addendum	na	na	19677 Rev. A				6.5 x 4.5" 12 pages, Jan 1992

¹ Connectors A = Antenna, P = Power, K = Key Load, I = I/O
Mating connector to make a Conaxll cable p/n 6282-7SG-3DC available from Electroshield

There is a plastic "CXA" 7 pin connector just behind the Antenna connector, where the computer I/O connector is on other Trimpack receivers.  Don't yet have a pin out for this connector, but it's a computer I/O connector, but not the standard military U-229 type.  The Manual Addendum says "TransPakII GPS Personal Nivigator with I/O".  The manual is dated 1992.  TransPakIIs shipped in February 1992 and later have a six-channel GPS receiver. The 6 channel version is part number 19437-60.

After connecting to a clip on vehicle power adapter and my house antenna using the two extra in-line DBS GPS amps, this receiver was tracking in less than a minute.  The eBay seller had used it prior to the auction and so the almanac was not that old.

In the Status (STS) menu, line 3 showed calculating satellite visibility for a number of minutes, then it changed to calculating window, cycle nnn, where nnn increments up from one.  Then "Full 24hour Coverage".  Window was a term used when there was not a full constellation of GPS satellites or when you are very far North or South.  The "Window" will forecast those times when you will have 4 or more satellites visible.

Menus

On the Set Up page if in line 1 you choose SEA mode then the last entry in line 3 can be changed from OFF to AV2 through AV10 which will average 2 through 10 fixes and display the result.  This does not change the computer data.  But you can not averave a lot os positions like in the Trimpack above.

On the Set Up page line 3 if you select NMEA then press "R>" you can turn on or off SETMSG, this allows turning on or off the following NMEA sentences.  These have the check sun turned on.

APB - Autopiolt format B ->
 $GPAPB,A,A,0.00,L,N,V,,002,M,100,002,M,002,M*40

BWC - Bearing & Distance to Destination waypoint ->
$GPBWC,144800.63,0000.00,N,04500.00,E,018,T,002,M,2432.1,N,100*2C

GGA - GPS Position ->
$GPGGA,144801.67,3911.41,N,12309.84,W,1,3,04,268,M,-24,M,*6F

GLL - Lat & Lon ->
$GPGLL,3911.41,N,12309.84,W,144802.42,A*11

VTG - Actual Track & Ground Speed ->
$GPVTG,012,T,356,M,0.02,N,0.03,K*4C

XTE - Cross Track Error
$GPXTE,A,A,0.00,L,N,V,,002,M,100,002,M,002,M*40

Check Sum - check sum

The TIME menu has:
line 1: DDMMMYY   HH:MM:SS  This is the full current Date & Time
line 2: ETA       ********     Estimated Time of Arrival to the selected Way Point
line 3: TTG       ********     Time To Go = time left until the way point
line 4: LAST FIX  HH:MM:SS     If the receiver is working from an older fix it lets you know

Two Computer I/O protocols:

• ASCII - may be very limited based on the Operation & maintenance Guide
  

• NEMA 0183 (APB, BWC, GGA, GLL, VTG, XTE
  RS-422, 4800 8N1.

Operation & Maintenance Guide for TransPakII. available from NEI.

Function Switch positions: OFF, POS, NAV,  TIME, DIST, WPT, STS, SET UP

Computer I/O

The NEI-16844 Data Cable is terminated with a DB-9(f) connector that plugs directly onto a computer RS-232 Serial port.  It works for both receiving and sending commands as is.  There is a difference between the pin out of this cable in terms of Tx- and Tx+, Rx- and Rx+ and the cable for the Trimpack above that I can't explain.  Both cables work or their respective receivers.

TransPakII Pin	Description	NEI-16844 cable DB-9(f)
1	Rx-	3 TXD
2	Tx-1	2 RXD
3	Tx+	nc
4	Rx+	nc
5	HQSEC2	9
6	GND	5 Gnd
7	Rxda3	nc

Note¹: there are no flow control jumpers, so the controller needs to be set for no flow control.
To see the data in Hyper Terminal:

• ASCII 9600 8O1 no flow control
• NMEA 4800 8N1 no flow control
  

Note²  There is nothing in the manual about pin 5, it may be Have Quick 1 PPS or HQ data, need to check with scope.
Note³ There is nothing in the manual about pin 7 Rxda, it may be an RTCM 104 DGPS data input.

L2 P-Code Receivers

These receivers are both 6 channel and P-code (L2 frequency) capable.   The most advanced in this line of GPS receivers.  SAGR, Centurion and Trimpack III are all names for these receivers.

SAGR

AN/ASN-169 Stand Alone air GPS Receiver is an upgraded SLGR by Trimble.  It looks very similar to the SLGR.

Part Number Table

Description	# Chan	Color	Trimble p/n	NSN	Con1	FW	Comment
Centurion	6 L1 L2		18154-00		A P K		same as SAGR  AN/ASN-169
Trimpack III Standard Positioning Service	6 L1		23365-00		A P K		Firmware does not support Key Load TB 5826-314-10
SAGR, AN/ASN-169	6 L1 L2	Black	20636-00-IN	5826-01-414-4147	A P K		seems to be two different NSN for the same p/n?
SAGR, AN/ASN-169	6 L1 L2	Black	20636-00-IN	6605-01-383-3377	A P K
SAGR - Antenna L1/L2	na	Black		5985-01-422-471?	A

¹ Connectors A = Antenna, P = Power, K = Key Load, I = I/O

Key Load Connector

This is a 6 pin version of the U-229 connector that's often used on military radios like the SINCGARS for Key Loading and/or AUDIO functions.

Pin	Function
A	+5 V Signal Referenced to ETD
B	ETD Installed
C	Request
D	Data
E	Clock
F	Spare

Common Features

The packaging and most accessories for all these GPS receivers is common.

Antennas

The Trimpack line needs an active external antenna with about 41 dB of preamp gain, but most active GPS antennas have about 20 dB gain.  That means they are short 20 dB (10 times voltage) the needed gain and therefore will NOT work on the Trimpacks.

You either need one of the antennas made for the Trimpacks or use an amplifier between the antenna and the Trimpack.

The Trimpack is specified to supply +5 Volts on the center conductor at up to 80 ma, but I think that if the antenna actually pulls 80 ma it will degrade the receiver, so less than 80 ma is desirable.

Some current needs to be drawn from the receiver so it can sense that an external antenna is connected.  Then power is removed from the internal antenna.  The Status page will display which antenna is being used.

Antenna Related Part Number Table

Description		Trimble p/n	Comment
Exteranl Ant for 16768-xx 4 x 3.75 x 0.5" SMA(f) thru hole mounting		12038-00	80 ma 3.5 - 4.5 VDC 12765-00 cable
6 meter Antenna Cable		12765-00
Aircraft Install kit		14726-30
marine antenna	white	14825-02	not tested labeled "Transpak" RG-6 coax
SLGR- Antenna Aircraft	Green	16248-40
Pathfinder	White	16741-00
3/4" high Aircraft Antenna	White	16248-10
Antenna, Type-N(f) connector	black ____ Olive drab	17572-00	probably  the 12038-00 ant on the 12960-00 surface mount adapter (actually is a 16248-40 ant)
L1/L2 External Antenna		22433-20
Mag Mount External Antenna		28367-40

 Military Antenna 17572-00

This antenna does work with the Trimpacks. 
Inside the case is a 16240-00 antenna.  The case holds the thin antenna and provides a Type-N(f) connector.  The bottom of the 17572-00 can be surface mounted to a vehicle or be screwed onto a modern surveying tripod that has a 5/8-11 male thread (or you can use a tripod adapter that screws onto  your 3.5-8 male thread and has the 5/8-11 male thread on top.

There four 0.275" dia. mounting holes on a 4.25" x 1.75" pattern in addition to the 5/8-11 female thread for a surveying tripod on the bottom.  It's interesting that this antenna has the survey tripod thread, the implication is that it has a well controlled phase center that's suitable for carrier phase surveying.  If you have any info on this please let me know.

Note by holding a light at one of the slots you can see inside, that's how I read the actual antenna p/n. No need to take it apart and take a chance of  breaking the small coax/

28367-40 Mag Mount Antenna - Does NOT work

comes with 16 1/2 foot of 1/8" diameter coax with an SMA(m) connector that mates to the Trimpack.  Is a small mag mount GPS antenna made by Trimble.  This antenna pulls 82 mA of current.  The spec for the Trimpack is 80 ma. 

When connected to the 14992-20 the receiver shows EXTernal antenna and does track some satellites, but not as many as with the internal antenna.  Maybe this antenna has a little less than the needed 41 dB gain.

When connected to the 16768-20 receiver the Status line that normally says GPS OK now says Receiver fault (16).  This is the fault that you get when the Ext Antenna SMA(f) jack is shorted.  The receiver does NOT switch to the external antenna and continues to operate from the internal antenna, but with the heavy current draw it does not work as well as with the 28367-40 disconnected.

Tried three different antennas on both receivers.  All three work OK on the 14992-20 and all three generate the Receiver fault (16) message on the 16768-20 receiver.  This must be due to a subtle difference in the threshold for determining when the external antenna is short.

It's not clear to me if this antenna should work and these are out of spec. or if this antenna should not work.

Antenna Connector

Antenna Connector is an SMA(f).  It has 5 VDC coming out to both power an external antenna and sense that there is an external antenna connected.  It may be that the external antenna needs draw current in a specified range, if the current is below some threshold the receiver senses not external antenna and uses it's built in antenna.  If the current is above some value the receiver uses switches to EXTernal antenna mode, but does not use the external signal.  I'm guessing this because of strange behavior I have seen.

14992-20 Antenna Voltage vs Current

Load Ohms	Voltage	Current ma
open	5.09	0
470	4.99	10.6
220	4.9	22.2
100	4.6	46
47	3.8	80.8

The Trimble Model 21423-00 white hockey puck active antenna (used with the SV6 receiver) draws about 22 ma.  By using a rubber band on a BNC-T connector and a BNC(f) to SMA(m) adapter you can get the Trimpack to think it's powering an active GPS antenna without overloading the power supply like a 50 Ohm load does, but the receiver still does not Track any sats, why?

Ans.: The Trimpack needs 41 dB gain in the antenna which is more than most active antennas provide.  This makes sense since the Garmin III+ and Motorola VP+ GPS receivers are designed to work with a passive antenna connected directly to the receiver.  The active antennas offered by Garmin and Motorola have a small amount of gain (typically < 20 dB) to make up for short cable runs.  The requirement for 41 dB of gain after the antenna, excluding any cable loss, is a lot different from what my other GPS receivers need.

11 Aug. 2003 - By adding two each Radio Shack 16-1156 In-Line DBS Satellite amplifiers and using the Wall wart power supply and Bias-T from a Radio Shack 15-1170 In-Line TV amplifier, plus a BNC-T connector next to the Trimpack with a 100 Ohm resistor to get the Trimpack to go into external antenna mode, the receiver is tracking between 5 and 7 satellites.  The Wall wart I'm using puts out about 13 volts when driving  a single satellite in-line amp, but only 10 volts when driving two of them.  Need a supply with more current capability, and that should add more gain.  I think this is needed because the Garmin III+ is tracking more satellites, and the Trimpack can track up to 8 satellites.

This was a mistake!  The roof top antenna was a Motorola hockey puck that wants to see 5 volts and it died when 13 volts was applied.  This happened because the 4-way divider has two ports that have a DC connection to the antenna and two that are DC isolated, and I did the above experiments on the port with the DC connection.

Radio Shack GPS Amplifier

Using the two Radio Shack Satellite in-line amplifiers and the external power connection for DC, the AN/PSN-10 has been running for a number of days and whenever I check the number of SVs being tracked it's always 3 or more, but rarely more than 7, even when the Garmin III+ is tracking 12 satellites.  The input to the two series connected amplifiers is from my house 4-way GPS power divider.

The In-Line satellite amplifier is an RCA D903 and is specified for 15 to 18 dB gain from 950 to 2050 MHz.  I checked it at 0 to 500 MHz and saw only loss.  The Input center conductor is tied to the output center conductor for DC so it will pass the DC bias through so multiple amplifiers and/or an antenna mounted amplifier can be driven through the coax.  The "TV" side of the Bias-T is DC blocked so that no DC is applied or taken from the Trimpack, hence the need for a resistor in that spot.

Current draw for the 2 DBS amplifiers is:

Voltage V	Current ma
5	10
6	14
7	19
8	23
9	28
10	33
11	36
12	37
13	37

Commercial L Band Amplifier

Attaching a commercial 50 dB gain L band (1 - 2 Ghz) amplifier to the output of the house 4-way GPS divider and directly into the PSN-10 works.  The AN/PSN-10 is tracking 6 satellites and the Garmin III+ shows 6 sats.  The interesting thing is that the STS page shows INT antenna.  This is because the commercial amplifier has a DC blocked RF output and so does not draw any current from the Trimpack.  BUT, I think the antenna input circuit is a power combiner, NOT a switch, so the strong signal from the external antenna jack is going into the receiver and being used.  The internal antenna is being powered but it can only pick up a couple of sats inside my house.  I confirmed this by turning off the DC power to the L band amplifier.  Then the PSN-10 only tracks 2 sats.

I think that all the Trimpacks work this way, but have not tested all of them yet.

Sensor Systems S67-1575-58 Passive GPS Antenna

About 2 1/8" diameter and 1/2" thick with a 1 meter long coax terminated with a right angle SMA(m) connector.  There are 4 each 6-23 tapped holes on a 1.3" square pattern on the bottom.

This antenna will NOT work with Trimpack receivers.

However it works well as a transmitting antenna when connected to the output of a high gain L-band amplifier.  Without using a power divider a number of GPS receivers can all be operational receiving the GPS signal from the antenna on my roof by means of amplification and reradiation.

19 Oct 2003 - With the AN/PSN-10 and TransPakII receivers sitting side by side (but separated by about 6" which seems to help) the TransPakII is much more sensitive.  They both are getting the signal transmitted from the Sensor Systems passive antenna.  For example the TransPakII is receiving 6 SV's while the AN/PSN-10 only is tracking 3 SV's.  Tried reversing their positions to see if there was a hot spot from the Sensor Systems antenna, but the number of SV's tracked stayed with the receiver not the position.  It's too bad that the TransPakII does not have the long averaging function, it only has a 10 second average when in SEA mode to average a ships position in swells..

Gilsson Technologies - might make an antenna that would work with the Trimpack, but the case I know about it isn't working.



14825-02 Trimble Transpak GPS antenna
The eBay ad mentions an RG-7 coax connector and this looks like a maring antenns.
The label in the photo says:
Antenna, Transpak GPS

Back Up Battery

All the Trimpack type receivers have a 3.6 Volt Lithium battery soldered to their digital Printed Circuit Board.  There is a Dallas chip that makes the RAM memory into a non volatile memory.  All of these batteries I've seen have been good.  It's now 2003 and some of these receivers were built in 1990.  The SV6 receivers have provision for an external back up battery.

It can take more than 12.5 minutes for a cold start because the receiver needs to download the complete navigation message from one satellite.  This can only be done after the receiver finds a satellite.  This message from one satellite has the almanac data for all the satellites so the receiver knows which satellites are in view.  Next the receiver needs to download the ephemeris from each satellite in view and then lock onto that satellite.

If the back up battery fails then every time the main battery is replaced the receiver will do a cold start.  But when the back up battery is working the receiver will do a hot or warm start and will acquire satellites within a few seconds of power on.  The exeception to this is if the receiver is moved more than 100 km while turned off, then it will be "lost" at power up and do a cold start.

Computer I/O

Hardware

Computer Interface Connector

This is a 6 pin version of the U-229 connector like is used on most military radios for the AUDIO interface.  Use a GC-283 plug.
It supports RS-422, but can be used for RS-232 on most modern computers as shown below.  Notice that there are no flow control signals so either you need to configure your computer port for no flow control  or jumper RTS to CTS so the computer sees hardware flow control.

I/O Cable

An official RS-422 to whatever level converter can be used since the Trimpacks use a 4 wire (TX+, TX-, RX+, RX-) interface, BUT you can also use a passive cable on most computers.  Here's what works for me:

Trimpack Pin	Function	Computer  DB-9(f) Plug
A	RX+	Circuit see1 below 3 Tx
B	TX+	2 Rx
C	TX-	no connection
D	RX-	5 Gnd
E	1 PPS out	1  DCD2
F	GND	5 Gnd

¹ I placed a resistor and diode in the connector shell of the DB-9 connector to limit the +12 Volt possible with RS-232 down to near +5 volts going into the Trimpack.  The first circuit limited the voltage swing to +4.3 V for high and 0.28 V for low and the Trimpack would not respond.  This circuit limits the swing to +4.8 V and -0.59 Volts and the Trimpack works fine.
From the DB-9(f) Tx pin 3 place a 100 Ohm resistor in series to Pin A on the Trimpack mating connector.
Place a 5.1 Volt Zener diode with it's cathode band from the wire from Pin A to DB-9 pin 5 (ground).

I was told by a Trimble employee that the Trimpack receivers do track carrier phase as part of the velocity determination algorithm.  But carrier phase is not available in any of the software data packets.

Software

Trimble has an ftp web page where you can download software for a number of their products, including a general purpose program called Trimble Studio.  Studio works with both TSIP and NEMA formats and so can be used with other barnds of GPS receivers.

Protocols

Different Models of receiver support different I/O protocols. 

Name	hw	Model	I/O connector	TSIP	TIPY	TAIP	NMEA	ASCII	Track-2
				9600	9600	4800	4800	9600	9600
				8O1	8N1?	8N1	8N1	8N1	8O1
Transpak	RS-422	14992-20	none	-		-	-	-	-
Trimpak	RS-422	16768-20 AN/PSN-10	U-229	YES	-	-	-	-	YES
TranspakII	RS-422	19437-60	Conxall	?		?	YES	YES	-
Centurion	RS-422	18154-00	U-229	->	YES	-	?	?	?
SV6	RS-232	21589-00	2 ea. DB-9(f)	YES	-	YES	YES	-	-
Placer	RS-232	18694-00	see below	-	-	YES	-	-	-

LabVIEW Driver

Now have a LabVIEW (5.1)  instrument driver that reads all TSIP packets and places them into an array.  Each row of the array is dedicated to a packet number (0 to 255 corresponding to 00h to FFh).  Individual VIs will be written to work with each documented packet.  As of 28 Aug. 2003 the following packets have been done:
35  Set/Request I/O Options - XYZ, Lat-Lon-Alt, Single or Double precision, etc.
40 Almanac Data for a Satellite
41 GPS Time, Week # and UTC Offset
42 Single Precision Position Fix in XYZ ECEF format
43 Velocity Fix, XYZ EDEF format
44 Tracking Mode and the SV #s of the 4 sats being used
46 Health of Trimpack
47 Signal strength
48 GPS System Message (22 ASCII byte message)
49 Health of all 32 Satellites
4A Single Precision LLA Fix
4B GPS Receiver ID
5B Ephemeris Data for one Satellite
5C Satellite sig srt, tracking mode, Az, El
6D Tracking mode and a list of all SVs being used
84 Double Precision Lon Lat Alt Position Fix (8 byte radion number for Lon and Lat, way more precise then Single presision on LCD and can be averaged.)

Note:  I received an email pointing out that there's a GPS week rollover bug in the ASCII protocol and display, but not the binary protocol. 

Since 23NOV -2006 dates displayed on old Trimble GPS receivers (such as Trimpack, Transpak, Scout and Explorer) have been wrong.

 

This seems to be a delayed rollover problem since dates have jumped back exactly 1024 weeks. It looks like Trimble avoided AUG 1999 rollover problems

by subtracting 7 years from the internal receiver times but still used modulo

1024 week arithmetic. At least 7 different models are affected in the same

way so it looks like Trimble has been copying old software code from one

model to the next without looking at it very closely.

 

Position and navigation have not been affected since they only depend

on the time-of-week.

 

The binary computer protocols are not affected since they use GPS week numbers and seconds-of-week but the ASCII protocols give wrong dates.

Mounting

13214-00 Trimpack Vehicle Mount

Can tip left and right, tip front to back using a wrench.

Can rotate using the lever to lock position.  So a driver or passenger could easily point the front panel.  The LCD in all the Trimpacks I've seen are best viewed straight on, not from above and not from below.

Power

Rear Attached Battery or Adapter

All of these Trimpack family GPS receivers use the same clip on rear battery pack.  This can be one of a number of battery packs or a vehicle cigarette lighter DC adapter.  The voltage must be in the range of 9 Volts minimum to 32 Volts maximum.

It can not be 6 Volts.  Using a BA-5800, which fits the small battery holder does not work.  The Trimpack gives a low battery error message and shuts down.

On some Trimpacks there is a yellow CAUTION label saying "Use of power sources other than Trimble approved battery packs may cause damage and will void warranty."  This same sticker has a "(+) symbol in the top right corner and a "(-)" symbol in the bottom right corner and that's the correct polarity to connect an external supply.  So my guess is that the sticker is there to tell someone how to hookup external power to the battery terminals and at the same time say if they do it backwards the warranty is void.

This means if you apply reverse polarity you will fry the Trimpack

Solution: Make up an external power cable with a reverse polarity protection circuit.  Place an enhancement type MOSFET (for <15 volts) the IRF511 would work, in the ground side of the circuit (source and drain) and a 1 Meg resistor between the gate and the positive supply line.  Better to clamp or attenuate the gate voltage so that when 32 volts is applied the gate stays below 10 volts.  See Fig 13.5 pg 164 "Troubleshooting Analog Circuits by Bob Pease.  ISBN 0-7506-9499-8

Description	Color	Trimble p/n	Comment
DC Adapter (Vehicle)	black	14934-00
Vehicle Power Adapter		22433-20
Large Battery Holder		13827-00	2 each BA-5800
Small Battery Holder	Green	13828-00	one BA-6800 or Trimble* AA holder
Small Battery Holder	Black	14902-00	"
NiCad Battery Pack		13829-00	battery pack not seperate cells
AA Battery Pack		18653-00
Vehicle Install kit		14726-20

* Note although the Trimble AA holder looks like a BA-5800, it is NOT the same.  It connects all the AA cells in series for a nominal 12 Volt supply with Alkalines, or a nominal 10.9 Volt supply with rechargable batteries.

14934-00 DC Power Adapter

This looks similar to the small battery back but it has a 12'-3' coiled cord coming out of the back center with a cigarrete lighter plug.  There's an ATO 3 Amp blade automotive type fuse in series with the positive lead.
Requires 9 - 32 VDC, 5 Watts

Batteries

These receivers run on 9 to 32 VDC and will not run on 6 VDC like is supplied by a BA-5800, but the small battery holder seems designed to hold a BA-5800.  The special 8 AA cell battery holder that Trimble supplies connects all the cells in series for a nominal 12 VDC supply.  They have made the contacts on their holder different from the bulls eye contacts on a BA-5800 to hopefully keep someone from using it in an application that's looking for a BA-5800.

A normal Alkaline AA cell has about 2.85 Amp hours so the 8 AA cell holder providing a nominal 12 VDC will last about 11.4 hours.  The current reduces as the voltage increases indicating a switching type power supply.  For input voltages of 18 and higher the current remains at 200 mA. 

Inside there is a 3.6 Volt AA size battery that keeps the data alive when the main battery is removed.  It is soldered into the receiver and mine measures 3.6 V, probably after about 10 years.  At some point it will need to be replaced.

The STS/Battery used: number can not be accessed by the menu switches, but after running the receiver for a couple of days from an 11 Volt power supply clipped to the rear terminals, I connected the battery pack filled with freshly charged NMH cells and the Battery used: number came on at :6:18. and after about an hour of use reads :7:23.  So it looks like one of the A/D channels is watching battery voltage and since all of the RAM is maintained it can tell there's been a change in battery voltage at power up.

The Low Battery warning starts flashing at 7.7 Volts.

At 11 Volts input the current is 197ma, 231 ma, 245 ma and 272 ma for the backlight off, and at three levels of brightness.

External Power Connector

The external DC power connector is located on the left side at the rear bottom.  It is part of the Back & Bottomcase half of the receiver that contains the power supply.  This is a standard U-229 connector like is used on most military radios for the AUDIO interface. Use a GC-183 plug.  Supply voltage should be 9 to 32 Volts.

Part Number Table for External Power

Description	Color	Trimble p/n	Comment
External Power Cable		12792-00	? delta to -10?
External Power Cable		12792-10	U-229 plug
Vehicle Power Adapter		13825-00	Metal Box
Vehicle Install kit		14726-20	? contents

Connector Pin Out for External DC Power Connector

Pin	Function
A	battery Ground
B	EXT GND
C	not used (internal gnd)
D	EXT +V,  9V to 32V
E	not used (battery gnd)

When operating on internal battery power the shorting cap must be installed.  This is truly a cap that shorts all the pins together.

12792-10 External Power Cable

U-229 Type plug with Red wire going through a 1 1/2 Amp Fuse to pin "D" and a black wire going thorugh a 1 1/2 Amp fuse to pin "B". 

It's important to have a fuse in the ground lead.  A number of PLGRs have been fried when they were connected to 12 Volts, but with the ground lead 12 Volts above ground, like in a military vehicle that has two12V batteries and the installer connected to the "top" battery instead of the "bottom" battery.

In my opinion Trimble got a lot of things right with the Trimpacks that Rockwell messed up on with the PLGR.

Related

SVeeSix

  Photo - 2 each SV6 receivers, the top one is a 23198-63 (1997 date code) TAIP protocol and the bottom one is a 21589-00 (purchased from Trimble in 1990) from an evaluation kit that supports: TSIP, TAIP and NMEA.

The SVeeSix and the TANS are a box with connectors, they have no human I/O capability.  The SVeeSix Trimble receiver uses the TSIP (Trimble Standard Interface Protocol) and a related manual I got from Trimble for the SVeeSix is the TANS (Trimble Advanced Navigation Sensor) manual. 

TANS  Trimble Advanced Navigation Sensor

The TANS is a metal box 5 x 8  x 2" with an SMA antenna jack, 3 pin power connector and a 22 pin circular mil connector for the I/O.  The I/O connector can be split out into 2 I/O connectors , like are on the SVeeSix.  The TANS will work with the 16248-00 Aircraft antenna, or the 12038 antenna.  The TANS will connect to an off the shelf Color Display Unit (CDU).  If  you know what this is let me know.

The other document Trimble supplied was Appendix A "Trimpack GPS receiver, Digital Communications Interface Definition" p/n 13498, Rev D, Nov 1990.  Which is the reference manual for the AN/PSN-10.

So you can see that the SV6 and TANS are also based on the same Trimble chip set as the Trimpack GPS receivers on this page.  I think a lot more Trimble receivers use the same core chip set.

Placer 100

 The Placer line of GPS receivers are designed to be  used in Automotive Vehicle Location (AVL) applications.  They would be connected to the 2-way radio and automatcially send the vehicle location to a central dispatch office.   No more "car 54 where are you".  The Label says p/n 18694-00 and references the same Trimble patnet number 4754465 as is on all the Trimpack type receivers.  I sw somewhere that this receiver is NOT compliant with the GPS week rollover.  But all the Trimpack type receivers are compliant.

There is a 37 male pin connector and a type-N(f) antenna connector.

DB-37	Pwr Wires
1 = Pwr Gnd	Black wire
20 = Pwr +	Red Wire
21 = Pwr +	Red Wire
	DB-25	DB-9
22 = Sig Gnd	7 = Sig Gnd	5 = Sig Gnd
23 = RS-232 TxD	3 = RD	2 = RD
24 = RS-232 RxD	2 = TD	3 = TD
25 = RTS	5 = CTS	8 = CTS
26 = CTS	4 = RTS	7 = RTS

Disassembly & Construction

Remove the two Phillips head screws and slide off the outer black plastic case.  Depress the two black plastic catches just behind the panel centered on the 5" x 8" faces and slide off the metal RFI shield.  Inside there are two Printed Circuit Boards.  

The "BLNK 14636" board has the 68HC0000, a couple of TNL 17609 chips a couple of 28 pin EPROMS marked 24427-1 and -2 and a couple of 28 pin SMT chips with a paper label TLNA 16593-01.  The RF front end is in a copper shielded box about 3" x 3" x 1/4" that has a 2x10 header to interface to this main board.

The second PCB "BLANK 17379" has empty spaces for a complete computer system and backup battery that are missing components.  The board does have a SMPS power supply and the TTL <-> RS-232 interface including line conditioning for 4 I/O lines.

The unit I got on eBay came with a DB-37(f) to DB-25 (f) cable with Red and Black wires for power.  Connecting the Radio Shack 26-209 Port Adapter to a standard DB-9(m) to DB-9(f) cable then to my computer, the Placer 100 is now outputting the TAIP LN (Long Navigation) message once each minute.  BUT, it is reporting some location far from where I am and it's been connected for a couple of hours.  There may be a couple of reasons for this: (1) It needs the high gain antenna like the Trimpack or (2) it is know to be non compliant with the GPS week rollover and so may need the correct date and time and a rough initial position to get started.

Using the amplified antenna that works for the Trimpack, had the Placer tracking within a few seconds.  It too needs the 41 dB gain antenna.

Connecting another Placer 100 that I'd never power before: for the first 14 minutes or so the loction was 32.7189085N 117.1651082W and then chenged to my location.  Since it takes about 12.5 minutes to download the current navigation message this is about right.

GPS Patents

4754465  Global positioning system course acquisition code receiver
This patent number is on all the Trimble GPS receivers I've seen.  A very innovative patent.  It greatly reduces the complexity of a GPS receiver compared to the prior art resulting in a smaller lighter receiver.  But the newer Trimble receivers have gone back to double conversion front ends to help reduce interfering signals.  Trimble also does not seem able to offer a 12 channel receiver using this technique.

Support

Trimble has turned over support of the Civilian versions of these to Navigation Electronics, Inc.  -

Links

GPS TRIMPACK -
GPS History - Trimpack and Gulf War
FAS - Desert Storm Navigation -
H_wright - eBay - Power cord for automotive use, similar to the 12792-10 above.
American MilSpec - Trimpacks for sale
Mike Murphy - Trimpacks for sale
eBay seller j5w23 often has the 8 AA battery box and holder for sale
eBay seller zuludelta often has the 17572-00 "Military GPS Antenna"

Possible 40 dB preamp L1 GPS Antenna Suppliers:

AeroAntenna - The AT575-75AW-TNCF-000-RG-36-NM may work with the Trimpacks.  It a 36 dB gain survey antenna (1"-14 female thread on bottom No Magnet) and works from 5 to 18 Volts (RG), uses a TNC(f) connector
Sensor Systems - S67-1575-58 Passive GPS Antenna makes a great re-radiator after a high gain amp.

DMF-50202N LCD Module Specs - includes how to adjust the contrast which fixed Manny's Trimpack low contrast problem.

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