3DR GPS Shield

Pedals2Paddles · Feb 3, 2017

Douglas A said:
Perhaps some enterprising soul among us can determine the 3m material they are using and sell them ourselves. Not exactly rocket science.

In fact, already happened. Someone here bought a whole damn roll of it. I don't have the model handy, but it is readily available.

BigTulsa · Feb 3, 2017

Douglas A said:
Perhaps some enterprising soul among us can determine the 3m material they are using and sell them ourselves. Not exactly rocket science. I guess I just find it a pity. Technology takes care of most of the staffing issues these days, and vendors and sub vendors even manage the 3rd party logistics. If you haven't guessed, I am in automotive logistics as provider, and manufacturers and suppliers push their work on us daily. I guess you just need the right people at the table to negotiate agreements, and to depersonalize it. I think I would have had a better experience with a soho company cutting them in their dining room. Just saying.

Ultimately I think the mRo GPS is better. Sure it might be more expensive, but in the long run it does better. 25 satellite lock proved it to me. With 0.5 hdop.

nuggetz · Feb 3, 2017

We're can I get one of those

Sent from my iPhone using Tapatalk

Douglas A · Feb 3, 2017

mRo GPS
mRo GPS u-Blox Neo-M8N / 3DR SOLO Upgrade

Whirlygig · Feb 4, 2017

If you have an mRo, do you have to also use either the copper shield or the $30 scrap of cardboard or both together? The mRo yt video says to use cardboard and the copper shield and I'm wondering if it's really necessary.

Douglas A · Feb 4, 2017

Please don't use the cardboard. It is bound to bite you at some point if it absorbs moisture. No good can come from that, and its been mostly proven that the shield is not really grounding out, but could. It is coated. There are several alternatives such as a thin piece of plastic, 2 strips of electrical tape, 3d printed versions, etc. Search the forum and you will find many. I have the mRo in use with the original shield and it picks up great. I will say my other Solo (rev B) has the 3DR v2 shield and it works great as well. Not as many satellites, however it was immediately noticeable that it had improved its cold start performance. Personally I think the GPS thing has been blown a bit out of proportion for most individuals who's units worked perfectly out of the box. I say this as someone who fretted over all this tirelessly, and now have tried most every combination. In the end my solo worked fine for my purposes out of the box, but I had to try them. YMMV

FamilyFlyGuy · Feb 4, 2017

Pedals2Paddles said:
In fact, already happened. Someone here bought a whole damn roll of it. I don't have the model handy, but it is readily available.

Haven't tried this myself, but I believe this might be the same as the shield material.

Electronics Product Catalog EMI Absorbers: Electronic Solutions : 3M United States

Douglas A · Feb 4, 2017

FamilyFlyGuy said:
Haven't tried this myself, but I believe this might be the same as the shield material.

Electronics Product Catalog EMI Absorbers: Electronic Solutions : 3M United States

Now I see why everybody isn't running out and buying it at $1000 a roll. Wow! Now that's some fancy tape

jbrunel · Feb 4, 2017

What about this stuff
RFID Blocking Fabric, EMI Shielding fabric
RFID Blocking Fabric, EMI Shielding for Wallets Lining, Purse lining, Pocket Lining

Whirlygig · Feb 4, 2017

Douglas A said:
Please don't use the cardboard. It is bound to bite you at some point if it absorbs moisture. No good can come from that, and its been mostly proven that the shield is not really grounding out, but could. It is coated. There are several alternatives such as a thin piece of plastic, 2 strips of electrical tape, 3d printed versions, etc. Search the forum and you will find many. I have the mRo in use with the original shield and it picks up great. I will say my other Solo (rev B) has the 3DR v2 shield and it works great as well. Not as many satellites, however it was immediately noticeable that it had improved its cold start performance. Personally I think the GPS thing has been blown a bit out of proportion for most individuals who's units worked perfectly out of the box. I say this as someone who fretted over all this tirelessly, and now have tried most every combination. In the end my solo worked fine for my purposes out of the box, but I had to try them. YMMV

Thank you for the warning and tip. I had fun switching out gps boards and making shields today. Turns out I had 2 rev A and 1 rev B. So, I swapped the 2 A for mRos and kept the rev B. I have also had decent luck with stock units out of the box, at least the Rev B which was giving me lock fairly regularly in less than one minute. But, I was occasionally losing gps signal (albeit briefly) which made me nervous especially flying over water so I decided to upgrade to be safe as possible.

Joe Horn · Feb 5, 2017

jbrunel said:
What about this stuff
RFID Blocking Fabric, EMI Shielding fabric
RFID Blocking Fabric, EMI Shielding for Wallets Lining, Purse lining, Pocket Lining

That stuff blocks 30Mhz-1500Mhz signals. Would that block the GPS signals? I read the Wikipedia page on GPS signals but the word "frequency" occurs 66 times and I gave up trying to figure it out.

RickP · Feb 6, 2017

Joe Horn said:
That stuff blocks 30Mhz-1500Mhz signals. Would that block the GPS signals? I read the Wikipedia page on GPS signals but the word "frequency" occurs 66 times and I gave up trying to figure it out.

The RFI shield material, if properly fitted, does not interfere with GPS signal reception. It's intent is to prevent the underlying Solo electronic RF emissions from degrading the reception of GPS signals by isolating the GPS antenna and ground plane as much as possible. It goes on the underside of the GPS module and does not block the antenna. The major systems (GPS, Glonass and Beidu) all use carrier frequencies in the 1.4 to 1.7 GHz range so you can see that the shield material referenced will attenuate a portion of unwanted signals. It's hard to say what the Solo electronics emit over the RF spectrum so the effect of the shielding can only be estimated. Cardboard does nothing. The latest Neo M8 technologies have better front ends to filter out and enhance signal but performance of a given maker's GPS board depends on the ground plane size and design, antenna feed and other layout considerations.

sputnik378 · Feb 7, 2017

RickP said:
The RFI shield material, if properly fitted, does not interfere with GPS signal reception. It's intent is to prevent the underlying Solo electronic RF emissions from degrading the reception of GPS signals by isolating the GPS antenna and ground plane as much as possible. It goes on the underside of the GPS module and does not block the antenna. The major systems (GPS, Glonass and Beidu) all use carrier frequencies in the 1.4 to 1.7 GHz range so you can see that the shield material referenced will attenuate a portion of unwanted signals. It's hard to say what the Solo electronics emit over the RF spectrum so the effect of the shielding can only be estimated. Cardboard does nothing. The latest Neo M8 technologies have better front ends to filter out and enhance signal but performance of a given maker's GPS board depends on the ground plane size and design, antenna feed and other layout considerations.

Damn. You've got some solid info there! I am really trying to decide whether or not I need to spend $30 to go with the $80 gps I recently put into my bird. I am still hoping someone on this forum will come up with a better offer for everyone and start cutting them out and selling them independently.

Currently I don't see the point of spending another $30 as my GPS lock has been much faster and for the most part very solid. There have been a few drops in GPS when I'm flying around, could it be possible this is due to interference? I guess the chances are pretty high. The other contributing factor is that I am mostly flying in stabilize mode these days as I need to get up 2000 feet to the top of the mountain as fast as I can and then back down again to chase the little skier snowboarder people. Until I started flying stabilize they always looked like ants because I could never drop fast enough with them.

Pedals2Paddles · Feb 7, 2017

I think a lot more people have mRO without the enhanced shield, and it worked just fine. The mRO is designed properly to filter out and reject a lot of the RFI that the shield is blocking. Ergo it works quite well without it. You do not need to throw money at it. If it works perfectly fine as is, there is nothing more you need to do.

RickP · Feb 7, 2017

I suspect the flaw in the initial (Rev. A) GPS board was poor layout design and implementation. The Rev. B board improved the design and works better. But the mRO boards use a different GPS chipset and the ability to utilize additional fix inputs from the Russian, Chinese and/or European galaxies. That in itself is the principal reason why it is so solid and even the Chinese-made clones are reasonably reliable.

Where some of the better boards excel is the ability to produce consistent fixes (low drift). This is influenced by the signal strength in (antenna and ground plane size matters) and the GPS signal processing capability of the chipset. The Solo board form factor is small with a relatively small antenna and ground plane. Additionally, it is buried within a plastic shell and the aft part of the antenna is partially obscured by the battery. A better design would have an unobstructed 360º view of the sky when the Solo is level. That would mean at least being on top of the battery pack. For the recreational use of the Solo, the current multi-constellation Neo M8 design is adequate. For more stringent accuracy requirements such as mapping, I would look at modification of the GPS using a reference board with a bigger antenna and groundplane and placing it external to the Solo body envelope. Some of these boards also have built in metal shielding around the GPS module grounded to the ground plane. The ultimate would be some kind of RTK implementation but that would require additional hardware like a base station.

I believe the inconsistent experiences of flyers WRT to GPS reliability has a lot to do with where and when you fly. Urban and hilly areas are very challenging with the constant motion of the Solo. Solar activity can also impair GPS signal strength. Those folks who have no problem with the Rev. A GPS may be flying in areas that are wide open, in good weather.

As P2P and others have noted, the mRO board seems not to be as sensitive to RFI.

carpy · Feb 7, 2017

RickP said:
I suspect the flaw in the initial (Rev. A) GPS board was poor layout design and implementation. The Rev. B board improved the design and works better. But the mRO boards use a different GPS chipset and the ability to utilize additional fix inputs from the Russian, Chinese and/or European galaxies. That in itself is the principal reason why it is so solid and even the Chinese-made clones are reasonably reliable.

Where some of the better boards excel is the ability to produce consistent fixes (low drift). This is influenced by the signal strength in (antenna and ground plane size matters) and the GPS signal processing capability of the chipset. The Solo board form factor is small with a relatively small antenna and ground plane. Additionally, it is buried within a plastic shell and the aft part of the antenna is partially obscured by the battery. A better design would have an unobstructed 360º view of the sky when the Solo is level. That would mean at least being on top of the battery pack. For the recreational use of the Solo, the current multi-constellation Neo M8 design is adequate. For more stringent accuracy requirements such as mapping, I would look at modification of the GPS using a reference board with a bigger antenna and groundplane and placing it external to the Solo body envelope. Some of these boards also have built in metal shielding around the GPS module grounded to the ground plane. The ultimate would be some kind of RTK implementation but that would require additional hardware like a base station.

I believe the inconsistent experiences of flyers WRT to GPS reliability has a lot to do with where and when you fly. Urban and hilly areas are very challenging with the constant motion of the Solo. Solar activity can also impair GPS signal strength. Those folks who have no problem with the Rev. A GPS may be flying in areas that are wide open, in good weather.

As P2P and others have noted, the mRO board seems not to be as sensitive to RFI.

I bought some copper tape on Amazon and printed this shield I designed for the mRo. It seems to help, although I never tested without it so not sure how effective.

Pedals2Paddles · Feb 7, 2017

The original version A GPS from 3DR wasn't just a matter of the component layout. It was actually lacking components required for filtering and rejection of RFI. The developers and engineers at 3DR did not want to do that, but the CEO insisted as a cost saving measure. Hence why those developers and engineers that were forced to sacrifice quality are now building their own components the way they should have been in the first place. The B revision GPS had the additional components but was limited late run. The mRO is totally different GPS (M8N), and does have the required filtering and rejection. As such, the mRO is far superior for both reasons.

BigTulsa · Feb 10, 2017

I know my brother when he made the mod on both our Solos used a 3d printed cover he fashioned (we have printers) using PLA black. I've flown it a few times with no problems. To be clear, the mod was the mRo GPS.

Pedals2Paddles · Feb 10, 2017

pious_greek said:
The recommendation from mRo regarding shielding is as follows:

we recommend to use the stock gps shield, or no shield at all. If you do decide to use another type of material please test the signal levals on the ground before you fly the aircraft as you take a risk of loosing the gps and not regaining the signal and this could cause the aircraft to have a flyaway or possibly crash.

I think the reason for this is probably because that's what Jordi and his team tested the product with, and they know it is fine with that. No business could or should recommend using a component they haven't tested with it to verify it is ok. I think it is a reasonable assumption that the new 3DR shield would be fine and couldn't possibly cause a problem. If anything it would help. However I think it says a LOT that the mRo works fine with no shield at all!