After working successfully for 18 months, I now get many drops in my internal GPS. Even sitting outside in the garden with a perfect view of the sky, GPS Status and Google Maps give perfect results, but Skydemon is 'Waiting for location' more than half of the time. This problem started about 6 weeks ago. 

Using SD 3.0.7.19226 on Android 4.4.4

I find that the free "GPS Status" android app (found here) is really useful for finding out about what's happening with your GPS and can be set to run in the background whilst SkyDemon is running. This may help to diagnose what's happening.

Simon

I am using GPS Status already. If I have trouble it shows 0/8 satellites. I think this means 0 satellites 'read' out of 8 visible. Right now it is fairly steady 8/8. The green flag in the ALT window shows, yesterday is was green/yellow/red.

While I am writing this, SD will show 'Waiting for Location' for a few seconds, and then resume. It is now off permanently, the first 10 minutes were steady on, now steady off. Regained contact...

I wonder if this has anything to do with the troubles in Ukraine?

I think that if GPS status is frequently flipping from 0/8 to 8/8 and back again it looks as though there is a problem with the GPS receiver in your device.

I think that SkyDemon uses the DOP (Dilution of Precision) figures which are shown by the GPS Status app to determine if the location is accurate enough to use (not sure what the actual values are that it requires - maybe Tim can enlighten us). It is likely that SkyDemon requires better accuracy than Google Maps etc before accepting the GPS output as usable for navigation.

Simon

I switched it on this morning. The first ten minutes it seemed to work normally, after that it goes downhill quickly. I think it is the internal GPS module going south when warming up. I have ordered an external Bluetooth GPS receiver just in case.

If you've got an android phone you can use it as an external bluetooth GPS by installing this app on your phone.

I made the first test flight today. GNS2000 is the bluetooth GPS receiver, Nexus7 is the slave running SD.
I checked 'Enable Mock GPS Provider' on.
GPS reception and position is good, but no groundspeed or course over ground. So on the SD screen, my position is OK but no speed vector shows up and it looks like I am flying backwards or sideways.

I use Bluetooth GPS app as the gobetween.

That sounds like a known problem with GNS2000 units. From memory, this only happened on the first units made and was subsequently solved by a firmware fix. Please check with the reseller you purchased your GPS unit from. This isn't really anything SkyDemon can help with.

Tim,

I know SD has nothing to do with this, I am just collecting information. I will contact GNS-gmbh in Germany for their support. Otherwise I send back the unit for refund.

Problem solved! Using 'Bluetooth GPS Provider' app for Android instead of 'Bluetooth GPS' solved the problem. Groundspeed and Course over ground are now correctly transmitted to Skydemon on Nexus. GNS 2000 works fine now.