GPS receivers

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My interest is in learning how to do as much as possible for the least cost. I have a Garmin eMap and a Garmin GPS 25-LVC module, and Trimble Ace II and Trimble Lassen SQ modules. I recently got a Magnavox GPS reference station.

For hobbyists probably the best place to turn is [Spark Fun Electronics], they have a bunch of other modules that I don't list here yet.

Garmin

Garmin OEM information

Model Accuracy Channels Price Comments
eMap 15m/2m 12 $200 or so Handheld, accepts RTCM for DGPS. Apparently a bad choice for Rinex software
GPS 10 15m/3m WAAS 12 $250 bluetooth module
GPS 15 15m 12 bare module
GPS 16 LVS, 16 HVS, 16A
3.3-6V / 6-40V / 8-40 V
15m / <3m WAAS / 3-5 USCG RTCM 12 channel 2 serial ports, deck mount
GPS 17 $200 basically the same as a GPS 16 but in a white, pole mount case
GPS 18 15m / 3m WAAS 12 $130 CMOS serial or RS232 or USB hockey puck
GPS 25-LVC (3.6-6V), -LVS(3.6-6V RS232), -HVS(6-40V RS232) 15m / 5m DGPS ? bare module; capable of raw data output (pseudorange and phase)

[1]

GPS 35 / 36 15m / 5m DGPS ? 35 = mouse style, 36 = pole mount

The GPS 17 is designed for marine applications but is often pressed into service in backpack style data collectors.

Trimble

GPS modules

Model Accuracy Channels Connectors Price (est) Comments
Pathfinder Pocket 10m/2m DGPS 8 2 RS232 via one DB9, SMB 3.3v, power $500 includes an external antenna.
M-Loc 10m (no DGPS) 12 3.3v 35mW(68mW)

25 x 25 x 6.9 mm

$45 FirstGPS software runs on host processor
Lassen SQ 6-9m,no DGPS 8 8 pin header, H-FL-R-SMT 3.3v/100mW
26x26x6 mm, 5.7g
$45 (use IQ instead!) Use w/RF transition cable
Lassen IQ 5-8m,no DGPS 12 8 pin header, H-FL-R-SMT 3.3v/85mW
26x26x6 mm, 5.7g
$50 Updated more accurate version of SQ. Purchase from SparkFun
Ace II 25m/2m DGPS 8 8 pin (2 CMOS TTL serial) SMB 5v/25mA 5v / 95mA / .47W
82.6 x 46.5 x 11.5 mm
cheap Discontinued but I got one from eBay for $10
Ace III 25m/2m DGPS 8 8 pin (2 CMOS TTL serial) SMB 5v/25mA 5v / 95mA / .47W
82.6 x 46.5 x 11.5 mm
$80
Lassen SK-8 25m/2m DGPS 8 8 pin (2 CMOS TTL serial) SMB 5v/25mA $ Discontinued; use SKII
Lassen SKII 25m/2m DGPS 8 8 pin (2 CMOS TTL serial) SMB 5v/25mA 5V / 95mA(120mA)/ .47W(.60W) $80
Lassen LP 25m/2m DGPS 8 2 serial and power via 8 pin header, MCX/3.3v 12mA 3.3V / 55mA(67mA)/ .182W(.221W)

66.167 x 31.75 x 12

$55 Low power; can be programmed to power up/down on schedule
Style Gain Connector Price
Micropatch 26dB 5m cable with MCX $17
Hardmount micropatch 26dB TNC $
Bullet 35dB 22m cable with SMB adapter $

DIY USB Lassen SQ

ToppTec -- purveyors of Trimble OEM modules

Delorme

http://www.delorme.com/

Consumer grade; Earthmates are WAAS enabled but the older Tripmates are cheap on eBay if you just need a NMEA GPS source.

Model Accuracy Channels Price Comments
Tripmate 15m? 12 $20-30 on eBay rs232 (discontinued)
Earthmate WAAS 12 $100 USB
Blue logger WAAS 12 $150 bluetooth enabled

Other links

Leica
Thales and Magellan
U-blox sells mostly Sony modules.

GPS simulators

People make boxes that simulate NMEA-capable devices to allow testing when the actual data stream is not available and to enable regression testing.

There is an Open Source GPS Simulator

GPS mission planning software

A GPS mission consists of three phases. planning, execution, and post-processing. Mission planning software packages run on a desktop system at your office and assist with planning and post-processing phases.

The two commercial programs that I know of are tightly integrated with the field software so they are not all that useful unless you buy in to the whole enchilada -- data collector, proprietary data collector software, and "office" software.

The two programs are Trimble GPS Pathfinder Office for use with Trimble data collectors and TDS SoloOffice which works with TDS SoloField.

Planning for a GPS mission should include checking for suitable conditions. This includes knowing that the satellites will be positioned propitiously when you will be in the field.

I use Trimble's free planning program for this. You can download it from [insert Trimbles download site]. The bad part is that it is available only for Windows systems but it's handy enough that I use it anyway.