PilotAware

British Forum => Technical Support => Topic started by: Lerk on September 03, 2018, 07:44:26 pm

Title: Failed GPS dongle
Post by: Lerk on September 03, 2018, 07:44:26 pm
Is there any history of GPS dongles going TEC?

My PAW has been intermittently failing and when it does the dongle appears to be dead (no LED).  This has been anywhere from instant to an hour into a flight.

I’ve bought a new dongle and fitted it this evening and so far it is holding steady after two hours so it looks plausible that the original dongle is somehow faulty.

I will add that my PAW is carry-on and until this weekend has been in the original case (albeit with the usb devices partially protected by the end of my Anker 22000 power-pack, so there may have been some physical damage to the package - but nothing is apparent.
Title: Re: Failed GPS dongle
Post by: Keithvinning on September 03, 2018, 08:06:18 pm
Hi lerk
How old is the unit
Classic or Rosetta

Keith
Title: Re: Failed GPS dongle
Post by: Lerk on September 03, 2018, 08:31:36 pm
Classic - bought in April B827EB4D0E8D
Title: Re: Failed GPS dongle
Post by: Lerk on September 04, 2018, 11:57:41 am
Ran last night and this morning for 9hrs without dropping so it certainly looks like the dongle was failing.
Title: Re: Failed GPS dongle
Post by: exfirepro on September 04, 2018, 12:56:04 pm
Ran last night and this morning for 9hrs without dropping so it certainly looks like the dongle was failing.

Hi Lerk,

They certainly aren’t ‘prone’ to failing, but I have replaced a couple of samples for customers because they were proving ‘unreliable’.

In my experience most gps problems are due to poor siting. The dongle type should ideally be mounted flat with the antenna (black printed side on the Classic Dongle) facing upwards. I use the ‘gps mouse’ which, whilst from the same u-Blox ‘stable’, allows better positioning and contains a bigger antenna, though lots of users simply put the dongle on a good quality * USB extension, which allows it to be sited on the coaming. The ‘mouse’ type also needs to be ‘right side up’ BTW - I have seen more than one mounted inside bodywork the wrong way up...

* This is important. As with the power supply, poor quality cables can seriously reduce the effectiveness of the device.

Regards

Peter
Title: Re: Failed GPS dongle
Post by: JCurtis on September 04, 2018, 05:49:08 pm
same u-Blox ‘stable’

The GPS dongles are clones of the u-Blox chipsets, they are not actually real u-Blox chips.  You can determine this by looking to set some of the specific parameters in them and the settings are simply ignored.  They are a generic GPS chipset that is emulating the u-Blox command protocols.

Though this was mentioned aeons ago now, they function OK, but some batches will be 'better' than others.
Title: Re: Failed GPS dongle
Post by: Lerk on September 06, 2018, 08:04:17 am
Going from 7-8 satellites working well to Absolutely nothing and the light going off sounds more like a board error to me...
As I mentioned in my OP I am happy to admit it may have been damaged in transporting the unit.
Title: Re: Failed GPS dongle
Post by: Keithvinning on September 06, 2018, 08:12:06 am
Hi lerk

Send me a PM with your address and I will send you a new one

Keith
Title: Re: Failed GPS dongle
Post by: Ian Melville on September 06, 2018, 10:28:59 am
Lerk,
I broke one at the solder joint between the PCB and the USB socket. Though I managed to resolder it, it was never the same again. So it was binned. Mine was without case so perhaps more vulnerable.
Title: Re: Failed GPS dongle
Post by: Lerk on September 06, 2018, 01:29:22 pm
It's ok Keith, I've got a replacement now - I was more interested in helping with feedback WRT a potential failure mode.

I will test those joints Ian - I've been a bit busy since the intial 'swap-it-out' repair.
Although I couldn't see any obvious break, it might have gone a bit high resistance - if low quality USB cables can cause an issue then a high resistance joint could also give the same problem.