Dave's list of unresolved clone issues:
1. Oplink radio link reception instability issues at range of about 107m
https://forum.librepilot.org/index.php?topic=1332.02. The above issue is made worst by the reconnection process which actually interrupts the failsafe of the drone by powering off the engines (stopping failsafe)causing a free fall that lasts 2 seconds (more if you have an arming sequence instead of "always armed"). This means its best to not reconnect if your drone has a return to base and land failsafe.
3. Arming: Sometimes works sometimes doesnt. I have now set my flight mode to stabalize with manual control of the throttle. So it's NOT because I have a GPS mode engaged. And yes I double checked that I was on mode one during the arming sequence.
UPDATE: I think this is just an issue of making sure all the lights are green in the FLIGHT DATA console. So if there is some stability issue need to rotate the flight board/drone to turn it green again.
4. Barometer is unstable and oscilates wildly even with the Altitude PIDs put to a sensible value (20,20,80 for QAV250 Chinese CLone instead of 100,70,90). There is a thread and wiki that explains how to pull out a certain component from the board but the boards I have came from a different supplier with a slightly different design.
https://forum.librepilot.org/index.php?topic=311.05a. Counter Intuitive System Settings:
Failsafe Throttle Settings: 1 = 100%. 0.1 = 10%. But in proper western English it should be 1 = 1% and 10 = 10%.
5b. Counter Intuitive System Settings Part 2:
Fail safe channel has a -1 offset. If you want to map your 3rd flight mode as a fail safe you have to set Fail Safe channel = 2. This is bad. We are not all programmers but as a programmer my self I know that the -1 offset is something that only programmers should have to deal with, not the consumer. To the consumer this is counter intuitive. The consumer should not be a programmer but be a software end user that can change settings INTUITIVELY.
5c. Counter Intuitive System Settings Part3:
Barometer Sensor in Systems->Settings->Object Objects->BaroSensor->Pressure = 99540 kPA
This should not have the "k". 99540 Pascals not kPA.
Conclusion:
We need a short list of good hardware suppliers in our wiki and forum(sticky points) so that people will know where to go to get non defective clones as all the original hardware products are discontinued. Version tracking only works if everyone sticks to the open source hardware schematics, unfortunately in China people have what we call in Australia: a "she'll be right attitude" about sticking to a rigid quality control routine.
UPDATE: I just added 5c. Developers please take note. Thanks.