Experiences with low cost M8N GPS modules?

TheRedEyeBandit · Aug 30, 2017

I just ordered the Mokao Ublox NEO-M8N BN-800 GPS Module from Amazon for aprox. $20 shipped. Also ordered the 3dr v.2 GPS shield… any one comment on this specific GPS chip?

Edit... I guess this is the same as the chip OP bought from Banggood? (the Manufacturer of the amazon post (Mokao) made me perhaps think this was clone of OPs GPS)

Pedals2Paddles · Aug 30, 2017

Nobody knows who made that GPS. Not even the seller. That is a risk you take purchasing cut rate random Chinese owned and manufactured devices. It was manufactured by someone, somewhere, at sometime, using unknown parts from unknown suppliers, with unknown (or no) quality standards, flashed with unknown and possibly hacked or stolen firmware that may or may not be consistent and reliable.

You saved $20, and purchased all of the above risk in doing so. As long as you comprehend that, and accept those risks... and are willing to accept the potential consequences, up to and including replacing $600-$1000 worth of drone and camera equipment in a crash, to save $20... Ok.

That said, the stock GPS is total junk to begin with. So virtually anything will likely work better.

TheRedEyeBandit · Aug 30, 2017

meh... risk accepted.

I also purchased 2 Mikrotik R11e-2HnD wifi cards this afternoon.

The Chinese GPS and the wifi cards will go in my spare (and inexpensive) revision A Solo that I recently got from ebay. I'll post w/ updates on how well it all works!!!

DJMc · Aug 31, 2017

TheRedEyeBandit said:
meh... risk accepted.

I also purchased 2 Mikrotik R11e-2HnD wifi cards this afternoon.

The Chinese GPS and the wifi cards will go in my spare (and inexpensive) revision A Solo that I recently got from ebay. I'll post w/ updates on how well it all works!!!

That's an interesting view of risk. Not sure how you can assess and hence accept it, given @P2P's totally valid assessment of the provenance of the components. What's the risk boundary you chose - the equipment, the equipment and you, or anyone/thing within the flight range of the Solo? How have you confirmed the components are safe to integrated in the system? What mitigations are you putting in place for not knowing the performance of a component with an intrinsic safety function in a complex vehicle?

I'm not sure, given the hard road of risk becoming realities that it's taken to get to manned aviation airworthiness standards where they are, that we'd want to contribute to the erosion of those standards for UAVs - particularly given the opposition to them that many already express.

I buy an mRo or a HERE - I know the company, I can read about the people and their experience and history and their understanding of the system they're manufacturing parts for. Same for MA props - long history, details on testing and manufacture - all available. I can satisfy myself of their likely performance.

I agree I have to pay for that yes, but it reduces risk to me - and others.

jca · Aug 31, 2017

P2P, DJMc....have you seen any evidence in this thread of problems with these cheaper GPS's? God, you're so uptight about it. That why this thread is here. So far so good for everybody that's used one. When someone has a problem feel free to jump in and say I told you so. Till then STFU.

Sent from my E6782 using 3DRPilots Drone Forum mobile app

BloodRed · Aug 31, 2017

jca said:
P2P, DJMc....have you seen any evidence in this thread of problems with these cheaper GPS's? God, you're so uptight about it. That why this thread is here. So far so good for everybody that's used one. When someone has a problem feel free to jump in and say I told you so. Till then STFU.

Sent from my E6782 using 3DRPilots Drone Forum mobile app

Seconded... if we don't try it, we will never find out.

Also, I recently installed BN-800 on my second Solo (first one has mRo). As mentioned by some others in this thread, it works like a charm... where mRo gets 20-22 sats, BN-800 got 18-19 during the test flights. So, if i was to buy another GPS upgrade, I would pick BN-800 over mRo any day.

DJMc · Aug 31, 2017

jca said:
P2P, DJMc....have you seen any evidence in this thread of problems with these cheaper GPS's? God, you're so uptight about it. That why this thread is here. So far so good for everybody that's used one. When someone has a problem feel free to jump in and say I told you so. Till then STFU.

Sent from my E6782 using 3DRPilots Drone Forum mobile app

Thanks for proving the point...and for the abuse in the reply.

Pedals2Paddles · Aug 31, 2017

jca said:
P2P, DJMc....have you seen any evidence in this thread of problems with these cheaper GPS's?

Did I claim anyone has? Did I even loosely imply anyone has? No.

jca said:
God, you're so uptight about it.

Explaining facts and reality for people to make a completely informed decision on a product is not being uptight. However, intentionally disregarding relevant facts to push your personal opinion while getting all mad and cursing is rather uptight.

jca said:
That why this thread is here

Yes. So people can make informed decsions. Which I am contributing to. This isn't an echo chamber where people are only allowed to agree with you.

jca said:
So far so good for everybody that's used one. When someone has a problem feel free to jump in and say I told you so.

In this thread, that you know of. Not so in the big picture. Again, I am explaining facts and reality for people to make informed decisions.

jca said:
Till then STFU.

No. And also, if you're trying to prove I am the bad guy, this doesn't help you delusional case.

andrew.baker.142 · Aug 31, 2017

TheRedEyeBandit said:
meh... risk accepted.

I also purchased 2 Mikrotik R11e-2HnD wifi cards this afternoon.

The Chinese GPS and the wifi cards will go in my spare (and inexpensive) revision A Solo that I recently got from ebay. I'll post w/ updates on how well it all works!!!

I would much rather have a GPS that I can implicitly trust over longer range WiFi cards. I easily get over 2000' with my stock system.
Remember the Here GPS also includes another compass, which installed properly should improve reliability even more.
As P2P said, the stock GPS is not so good so these knock-off GPS units are probably an improvement. I just think the additional $20 is worth spending for the Here GPS.

J0S0L0 · Aug 31, 2017

The reaction to the BN-800 GPS. I feel people are free to promote and celebrate their products and services any way they please, good business or not... I do know my copy of the BN-800 GPS has performed way above my expectations, in all situations. I give you a screenshot from this past Tuesday, the numbers speak for themselves...

holditnowfilms · Sep 1, 2017

Y

Just tested both my original version A with cardboard mod vs M8N BN-800 I test in an area with concrete and overpass a storm culvert as well as dirt berms and trees.

Both performed equally well. M8N gets more sats and is a bit more steady but did lose signal at one point near the overpass as I slowly approached it. Could have been weird anomaly but original never lost signal so I suspect maybe the antenna on the BN-800 is not as good.

I could fly both to the mid point of the overpass (underneath) before losing signal.

If I fly a fast direct route I can fly under no signal loss. Either GPS

My thoughts are this. The BN-800 gets more sats and holds solo in place better but is more susceptible to signal loss. Very quick and regains signal with minimal movement up or out.

Original gen A drifts a bit but holds signal of the few sats it gets better.

Start up times were equal.

KDan · Sep 3, 2017

holditnowfilms said:
View attachment 6911 YView attachment 6912 Just tested both my original version A with cardboard mod vs M8N BN-800 I test in an area with concrete and overpass a storm culvert as well as dirt berms and trees.

Both performed equally well. M8N gets more sats and is a bit more steady but did lose signal at one point near the overpass as I slowly approached it. Could have been weird anomaly but original never lost signal so I suspect maybe the antenna on the BN-800 is not as good.

I could fly both to the mid point of the overpass (underneath) before losing signal.

If I fly a fast direct route I can fly under no signal loss. Either GPS

My thoughts are this. The BN-800 gets more sats and holds solo in place better but is more susceptible to signal loss. Very quick and regains signal with minimal movement up or out.

Original gen A drifts a bit but holds signal of the few sats it gets better.

Start up times were equal.

I concur with the sensitivity of the antenna. I has been documented elsewhere that the taoglas antenna is slightly more sensitive that the cirocomm in the BN-800. I recall a discussion on the DIY forums quite sometime ago about the idea of transplanting the taoglass antenna. I don't think that anyone ever did it.
As for startup times, I've found the BN-800 to be substantially faster in every case compared to both of my original REV B units.

KDan · Sep 3, 2017

J0S0L0 said:
The reaction to the BN-800 GPS. I feel people are free to promote and celebrate their products and services any way they please, good business or not... I do know my copy of the BN-800 GPS has performed way above my expectations, in all situations. I give you a screenshot from this past Tuesday, the numbers speak for themselves...

View attachment 6907

My experience matches yours. I've also seen 21 satellites and 0.5 HDOP. Of course these observations and facts won't means anything to the naysayers. They've missed the whole point of the thread. They also seem insistent that results like these are a fluke, whereas the evidence thus far is that the solid performance of the BN-800 is the norm. I'm sure the attacks will continue, and they will continue to make claims and insinuations that are not backed up verifiable facts or evidence. They offer only hearsay evidence. As as engineer, I learned many years ago that hearsay evidence is next to worthless. You must do your own tests in many circumstances if you want the truth.

skyhax · Sep 3, 2017

All three of my sub $31 GPS units continue to perform great. With the $18 being the best and often getting 24 satellites. All 3 do something the OEM GPS did not do for me. They improve from copper tape shielding and you can see a difference by taping and un-taping different areas of the Solo. Most days they never lose GPS lock even under a heavy tree canopy. So I detect no performance loss from cheaper antennas.

DJMc · Sep 3, 2017

KDan said:
My experience matches yours. I've also seen 21 satellites and 0.5 HDOP. Of course these observations and facts won't means anything to the naysayers. They've missed the whole point of the thread. They also seem insistent that results like these are a fluke, whereas the evidence thus far is that the solid performance of the BN-800 is the norm. I'm sure the attacks will continue, and they will continue to make claims and insinuations that are not backed up verifiable facts or evidence. They offer only hearsay evidence. As as engineer, I learned many years ago that hearsay evidence is next to worthless. You must do your own tests in many circumstances if you want the truth.

I spoke about the seemingly blasé acceptance of risk, not performance in isolation - presumably as a fellow good engineer you'd support the inclusion of risk assessment and mitigation as part of testing?

Pedals2Paddles · Sep 3, 2017

KDan said:
'm sure the attacks will continue, and they will continue to make claims and insinuations that are not backed up verifiable facts or evidence. They offer only hearsay evidence. As as engineer, I learned many years ago that hearsay evidence is next to worthless. You must do your own tests in many circumstances if you want the truth.

Please cite these "attacks" you claim we're making. No such thing exists. If you're an engineer and you hate hearsay so much, you should probably stop using your own hearsay and fiction to defend your point of view.

holditnowfilms · Sep 3, 2017

Oh and this

My pull the T ant off my 3DR and put it on my M8N. Looks easy enough. Why not. My BN-800 gets loads of Sats but could use a better Antenna.

David Boulanger · Sep 3, 2017

I guess everybody has their priorities. I have four mRo units and missed out on the whole Here thing. But I can tell you this from experience. I carry $1000 of camera under my Solo. I get 28 Sats and a HDOP of under 5. I have had no momentary loss of GPS. No drift. Flew when the estimated KP index was 7. I prefer to buy from a reputable dealer. Here and the mRo qualify for that. Just the psychological aspect on me while flying is well worth the money spent buying from a known company that I believe in .

holditnowfilms · Sep 3, 2017

David Boulanger said:
I guess everybody has their priorities. I have four mRo units and missed out on the whole Here thing. But I can tell you this from experience. I carry $1000 of camera under my Solo. I get 28 Sats and a HDOP of under 5. I have had no momentary loss of GPS. No drift. Flew when the estimated KP index was 7. I prefer to buy from a reputable dealer. Here and the mRo qualify for that. Just the psychological aspect on me while flying is well worth the money spent buying from a known company that I believe in .

Makes total sense. There is a lot to be said for peace of mind. Plus you get support and faster delivery times and if your GPS had an issue it would be easy to return. I get that.

I personally have no fear of this GPS mod failing. It may lose signal but only in extreme cases not when flying relatively open areas. Which for me was only when I tested the limits next to and under an overpass

The actual HDOP is always really low. Well below 1 when I fly. So that's not an issue at all. Any GPS with low HDOP will perform the same. Sat data is sat data. All GPS systems have to over come the same Errors to find accuracy. The math is the same no matter what the brand.

I have not seen any indication that generic GPS mods have a higher failure rate. If they work out upon arrival they seem to keep working. No stats for any GPS on board failure rates.

Again the HDOP number is all that matters really. If your GPS is getting a good number it's all good. I have not gone beyond my ability to acquire good numbers with my current flying needs. So once I swap antenna I should be 100% even in noisy environments

holditnowfilms · Sep 3, 2017

I would note - I will upgrade to a HERE system with a mast at some point. Why? Because it's just too tempting not to. It's fun modifying a solo. I'm not gonna lie.