Hi there! I've just done my second power on test since I have been waiting for my MK USB to arrive. The first time I tested - a week ago - there was a problem powering on the Flight Ctrl. I've fixed the molex, and now it powers on, so yay, success... BUT! What was working a week ago was all the motors. They were reacting when I powered on the bird. But now only three of them (1, 4 and 6) are reacting, when I connect the LiPo (they do that sound thingey ) There's no problem with the motors, it's the same when I switch them around. I guess this isn't normal behaviour? Is there a way to test the solder points from the battery connection around the board? Please help. I'm so worried that I'll have to solder a whole new PDB with new BL-ctrls. Thanks! Regards, Sejer
Hi Sejer: You don't mention whether you have a Cinestar 6 or 8, but check on the undersize of the PDB -- do each of the BL-Ctrls have a green LED or are some of them red? Also, with MK Tool connected, check the Mixer tab. Do you have Octo2 selected (for a Cinestar 8). If not, what do you have selected. Could you post a screen capture of the Easy Setup window in MK Tool? Andy.
Hi Andy, I'm working on the Cinestar 8. I've just checked with motors disconnected, PDB powered on and Flight Ctrl connected and set to Octo2. BL-ctrls 3, 7 and 8 does not light up. The other controllers have green and red LED lighting up. I have checked every solder I've made from the BL-ctrls to the PDB from 3, 7 and 8, and I can't seem to find anything that shouldn't make them work. Any idea how to check them? I also get an I2C Error from the MK Tool when I connect to the Flight Ctrl via USB. Cheers, Sejer
Hi Sejer: If the motors are disconnected, that might trigger other problems. I'd try with the motors connected to the BL-Ctrl but with the propellers removed! Check the Molex connector between the FC and PDB -- that's how the I2C bus gets to the PDB. You can also try soldering two wires from the C and D pads on the FC to the C and D pads to the PDB -- that's the original way of connecting the I2C bus. Several folks on the forum wire the FC/C to PDB/C and FC/D to PDB/D even with the Molex connector in place as a backup in case the Molex cable comes loose. It sounds like you assembled the BL-Ctrls and soldered them on to the PDB yourself, right? If so, can you verify that you got the addressing on each of the BL-Ctrls correct? I'm trying to think of what else it could be. The fact that there are NO lights on BL-Ctrls 3, 7, and 8 suggests that they're not getting ANY power from the PDB. Can you confirm that with a Volt meter? You may have seen this page: http://www.mikrokopter.de/ucwiki/en/BL-Ctrl_Manual It has a video on how to test the BL-Ctrl. See also the section on Commissioning. Andy.
I figured out I had some loose connections from the capacitor solderings from the BL-ctrls to the PDB on pretty much all the BL-ctrls. So I'm redoing them, and the LED's start lighting up. Phew! What I'm worried about now is them coming loose again once in flight because of vibrations. I've never had such problems soldering, but it seems pretty hard to get the blop of solder onto both the pins from the capacitors and around the connection on the PDB. Any tips here? As the I2C bus problem goes, I'm going to make the connections from the FC to the PDB as you suggested. But as my solderings from the capacitors are kinda crappy, can the problem be caused by same bad solderings from the PDB/C's to BL-ctrl/C's and PDB/D's to BL-ctrl/D's? I start to regret that we didn't buy a presoldered PDB. Oh, and great DVD by the way, Andy. It's really helpful!
No real magic bullet for those solder joints, Sejer, I'm afraid. All you can do is make sure the tip of the soldering iron is clean and heat up the joint just enough to flow the solder so that you get bright, shiny, joints. Be sure to put a blob of hot glue between the cylinder of the capacitor and the PDB to hold it securely so that the mass of the capacitor cannot waggle up and down and fatigue the wires and the solder joint. I'm afraid bad soldering can indeed cause I2C bus problems, however, if you also have the Molex connector in place those wires will serve as a backup. You might want to do a Google search for "Learning to solder" -- there are quite a few YouTube videos that show you the best techniques. Glad that you found the DVD helpful too! There's a second on on MK Tool available from quadrocopter. And also a third one on MK_GPXTOOL and Google Earth that describes how to analyze GPX log files written to the microSD card on the Navigation Control board -- I'm just waiting for QC's approval to go to replication on that. Andy.
I'll be sure to check the joints then. I'd love to get the MK Tool DVD as well. Only thing is that it's incredibly expensive to have it imported in Denmark where I live. Maybe I can have a fellow American send it to me as a private package and avoid the taxes. Thanks for your help. I'll let you know how I progress! Sejer
Good news. After resoldering all the solder joints, all is working as expected. Almost time for my first flight. Thanks for all the help Sejer