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This is a GNSS module with both GPS and GLONASS support.

It is pin-compatible with the Adafruit Ultimate GPS, which is to say, PPS is on pin 1, 5V is on pin 2, and so on (full list below). 

But instead of using the PA6H chip from Global Top, built on the MT3339 from MediaTek, it uses the GMS-G6 chip, built on the MT3333. 

There are two major differences: First, the GMS-G6 supports both GLONASS and GPS. Second, the GMS-G6 doesn't support an external antenna and can only use the integrated ceramic patch-on-top antenna. The PA6H used in the Ultimate GPS does not support GLONASS, only GPS, but it does support an external active antenna and has a u.FL connector for that.

Why buy from me?
1) Pin headers and battery holder attached.
2) Battery included (United States only.)
3) EPO data downloaded.

You don't have to spend time soldering. It can be a pain to keep those pin headers at a right angle. Putting that battery holder on straight and level can be hard. Then there's the alcohol bath to clean off the flux. I do all that for you.

And there's that CR1220 battery. Such a pain to drive around to stores trying to find just one. It keeps the NVRAM alive so when you yank the power for a second, the GPS chip remembers what it was doing last and doesn't have to start from scratch. I include it. (Unless you're outside the USA. Shipping regulations, passenger planes, all that stuff. But I lowered the shipping price by a dollar, so it's fair.)

Finally there's the EPO data. Basically it's a hint file with two weeks of future orbit predictions; I download and install that to help you get a faster lock the first time you plug the module into your breadboard.

You might really enjoy my "Ultimate Helper" adapter board which provides both a USB and DB9 serial interface to this board; it's available here on eBay.

A screenshot from VisualGPSView of the module when it was indoors, afternoon, and eight feet from any window.
(Click to enlarge, double-click to make small again.)

Pinout:
1: PPS
2: 5V
3: Ground
4: Receive
5: Transmit NMEA
6: Fix
7: Battery Power
8: Enable
9: 3V3 Out

Sample NMEA stream:

$GNRMC,092147.000,A,3359.3073,N,11828.1481,W,0.40,266.46,280315,,,A*63
$GPVTG,266.46,T,,M,0.40,N,0.74,K,A*3A
$GPGGA,092148.000,3359.3072,N,11828.1482,W,1,6,1.25,14.6,M,-34.0,M,,*52
$GNGSA,A,3,12,25,05,21,29,,,,,,,,1.53,1.25,0.89*15
$GNGSA,A,3,72,,,,,,,,,,,,1.53,1.25,0.89*19
$GNRMC,092148.000,A,3359.3072,N,11828.1482,W,0.42,266.46,280315,,,A*6C
$GPVTG,266.46,T,,M,0.42,N,0.78,K,A*34
$GPGGA,092149.000,3359.3072,N,11828.1485,W,1,6,1.25,14.6,M,-34.0,M,,*54
$GNGSA,A,3,12,25,05,21,29,,,,,,,,1.53,1.25,0.89*15
$GNGSA,A,3,72,,,,,,,,,,,,1.53,1.25,0.89*19
$GNRMC,092149.000,A,3359.3072,N,11828.1485,W,0.46,266.46,280315,,,A*6E
$GPVTG,266.46,T,,M,0.46,N,0.84,K,A*33
$GPGGA,092150.000,3359.3072,N,11828.1487,W,1,6,1.25,14.5,M,-34.0,M,,*5D
$GNGSA,A,3,12,25,05,21,29,,,,,,,,1.53,1.25,0.89*15
$GNGSA,A,3,72,,,,,,,,,,,,1.53,1.25,0.89*19
$GNRMC,092150.000,A,3359.3072,N,11828.1487,W,0.44,266.46,280315,,,A*66
$GPVTG,266.46,T,,M,0.44,N,0.82,K,A*37
$GPGGA,092151.000,3359.3071,N,11828.1486,W,1,6,1.25,14.5,M,-34.0,M,,*5E
$GNGSA,A,3,12,25,05,21,29,,,,,,,,1.53,1.25,0.89*15
$GNGSA,A,3,72,,,,,,,,,,,,1.53,1.25,0.89*19
$GNRMC,092151.000,A,3359.3071,N,11828.1486,W,0.05,266.46,280315,,,A*60
$GPVTG,266.46,T,,M,0.05,N,0.09,K,A*31
$GPGGA,092152.000,3359.3071,N,11828.1487,W,1,6,1.25,14.4,M,-34.0,M,,*5D
$GNGSA,A,3,12,25,05,21,29,,,,,,,,1.53,1.25,0.89*15
$GNGSA,A,3,72,,,,,,,,,,,,1.53,1.25,0.89*19
$GPGSV,3,1,10,29,75,030,28,21,42,283,21,25,42,203,26,05,40,048,17*7A
$GPGSV,3,2,10,18,21,213,,15,21,140,,13,18,101,,12,16,173,22*7B
$GPGSV,3,3,10,02,12,069,,31,01,270,*70
$GLGSV,3,1,09,65,64,081,,88,55,032,,66,39,177,,81,28,320,*6E
$GLGSV,3,2,09,87,26,092,,72,21,032,22,79,18,289,,78,12,241,*65
$GLGSV,3,3,09,80,01,341,*53
$GNRMC,092152.000,A,3359.3071,N,11828.1487,W,0.33,266.46,280315,,,A*67
$GPVTG,266.46,T,,M,0.33,N,0.61,K,A*3A
$GPGGA,092153.000,3359.3073,N,11828.1487,W,1,6,1.25,14.4,M,-34.0,M,,*5E
$GNGSA,A,3,12,25,05,21,29,,,,,,,,1.53,1.25,0.89*15
$GNGSA,A,3,72,,,,,,,,,,,,1.53,1.25,0.89*19
$GNRMC,092153.000,A,3359.3073,N,11828.1487,W,0.58,352.34,280315,,,A*6A
$GPVTG,352.34,T,,M,0.58,N,1.08,K,A*3A
$GPGGA,092154.000,3359.3072,N,11828.1486,W,1,6,1.32,14.4,M,-34.0,M,,*5F
$GNGSA,A,3,12,25,05,21,29,,,,,,,,2.36,1.32,1.96*1C
$GNGSA,A,3,72,,,,,,,,,,,,2.36,1.32,1.96*10
$GNRMC,092154.000,A,3359.3072,N,11828.1486,W,0.18,352.34,280315,,,A*69
$GPVTG,352.34,T,,M,0.18,N,0.33,K,A*37
$GPGGA,092155.000,3359.3072,N,11828.1486,W,1,6,1.25,14.4,M,-34.0,M,,*58
$GNGSA,A,3,12,25,05,21,29,,,,,,,,1.53,1.25,0.89*15
$GNGSA,A,3,72,,,,,,,,,,,,1.53,1.25,0.89*19
$GNRMC,092155.000,A,3359.3072,N,11828.1486,W,0.15,352.34,280315,,,A*65
$GPVTG,352.34,T,,M,0.15,N,0.28,K,A*30
$GPGGA,092156.000,3359.3070,N,11828.1483,W,1,6,1.25,14.4,M,-34.0,M,,*5C
$GNGSA,A,3,12,25,05,21,29,,,,,,,,1.53,1.25,0.89*15
$GNGSA,A,3,72,,,,,,,,,,,,1.53,1.25,0.89*19
$GNRMC,092156.000,A,3359.3070,N,11828.1483,W,0.22,352.34,280315,,,A*65
$GPVTG,352.34,T,,M,0.22,N,0.40,K,A*3A
$GPGGA,092157.000,3359.3069,N,11828.1482,W,1,6,1.25,14.3,M,-34.0,M,,*53
$GNGSA,A,3,12,25,05,21,29,,,,,,,,1.53,1.25,0.89*15
$GNGSA,A,3,72,,,,,,,,,,,,1.53,1.25,0.89*19