It's OK, I could've been more clear about my experience, but I tend to type as fast as I can before my son demands attention.  I do want to eventually try and make my own board. Not design one, simply copy the basic version with an aim at quality components, maybe an unusual PCB color just for fun.

 So it sounds like no special configuration is needed for the Pixhawk or Naza Gps unit? I do have a Naza GPS, but it's on a larger machine I am planning to sell next week. I will definitely order some of those connectors you linked to. Because I went so far over my spending budget, I have to sell a couple racing frames, and ideally my large hex before I can spend even the $30 bucks on a GPS unit. I may post the racers here just to see if anyone's interested. I am in Japan, so shipping the hex would not be worth it for most.

 Thanks again for the info. I think with this forum being new, and with the confusion from the separation, it is good to give too much info rather than not enough since others will surely read this thread, and learn from it.

Mateusz

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So it sounds like no special configuration is needed for the Pixhawk or Naza Gps unit?

You know it, but for completeness and for other users GPS and Mag are separate things, it just happens that it is convenient to put AuxMag inside GPS units.

Ublox GPS you connect serial line and with right connector and when you power system on, the Revolution board will automatically configure your Ublox GPS module and you get coordinates. That even works with released LibrePilot software.

If you want to utilize AuxMag which is different device from GPS, it is included in some GPS units, then you need to build development branch (Unless you have OP GPS that has AuxMag and that is supported in released software).
Change connectors and set that in GCS that it is either I2C AuxMag or Mag on Naza GPS unit. You can also buy AuxMag (hmc5883l) alone and connect it over I2C. But it is good to place it far from other electronics that draw current and mount it in the same way (orientation and level) as internal Mag.
If it happens that you want to use AuxMag inside GPS unit, and it is by design mounted differently than internal magnetometer in Revolution, then you need to change AuxMag Board Rotation in GCS to correct for that, because by default software assumes Mag orientation is the same, but any design can have that located differently.


So, two more quick questions. 1) what is the quality of the open pilot GPS vs an M8n? Is the OP GPS multiconstellation, what is the average satellite count, HDOP, lock time etc.. Also what is a good source for the OP GPS?

hwh

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So, two more quick questions. 1) what is the quality of the open pilot GPS vs an M8n? Is the OP GPS multiconstellation, what is the average satellite count, HDOP, lock time etc.. Also what is a good source for the OP GPS?

The OpenPilot GPS Platinum (aka V9) that's supported in the release version of the software was a Neo-7n based gps with a mag on it.  It's no longer made and currently the DJI Naza gps and it's clones are the closest thing to it.  I normally recommend them the same as Mateusz did.

The ones you see advertised on eBay and the Chinese sites as "OP GPS" are tiny gps units without a mag and with low gain antennas to make them small (around 20mm x 25mm).  They might be necessary for a very tiny quad but aren't recommended for bigger ones.  They also tend to run hot for some reason, probably a design flaw.  I have two, one I ordered to test and one that came in a package. Both run hot enough you can still touch them but they're very warm bordering on hot to touch.  I don't normally fly either one.  A developer I know has one that the voltage regulator chip melted and failed.


  It's no longer made and currently the DJI Naza gps and it's clones are the closest thing to it.  I normally recommend them the same as Mateusz did.

The ones you see advertised on eBay and the Chinese sites as "OP GPS" are tiny gps units without a mag and with low gain antennas to make them smal...  I have two, one I ordered to test and one that came in a package. Both run hot enough you can still touch them but they're very warm bordering on hot to touch.  I don't normally fly either one.  A developer I know has one that the voltage regulator chip melted and failed.

 So just to be absolutely clear any GPS that is intended for NAZA, like the M8n ebay, glb type will work?

 As for the hot mini gps's, I assume that is why many listings say "not intended for lengthy flights". My plan was to avoid these units, so no worries. My pixhawk machine has dual GPS units, an M8n and a newer 7 series. I have grown accustomed to very solid lock from the M8n, and am aiming for the same with the Revo.

hwh

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It's impossible to say positively that all gps on eBay that say intended for Naza are the right type but if I search eBay for "gps m8n naza" the first dozen or so entries that I checked are the right one.  I'm not sure what you mean by "glb type".

If you're thinking of purchasing one on eBay post a link to the auction here and someone can probably tell you if it's the right one.

Understood, and thanks. I am probably a couple weeks away from ordering a GPS unit.

 GLB = Good Luck Buy