I think the insurance question deserves its own thread.....! Josh, do you receive telemetry with your new system? Do you have a serial downlink? I'd be curious to know what your MK is reporting for altitude during the flight.. Maybe that's a good way to diagnose the AH problem... You can always borrow my xbee if you want to do some tests, if you don't have a serial link already... Best, Ben
Ben, Yes I do have xBee on my copter. According to everything I see it's reporting the correct Alt. during flight. I just did a flight using 6s batteries today and wow it fly's so much smoother... should have just done 6s from the beginning. I just ordered 4 more 6000mAh 6s batteries. I am hoping they are here before Thursday since I am leaving for a shoot. Now I have 8 5s batteries that I probably won't use again... or at least till I build a second copter. I will be making some other modifications to the FC so I can power the FC with the 6s batteries and NOT with the BEC. I don't like not knowing what the batteries are during flight. I attempted Alt. Hold again today with the 6s batteries and I could control it a little better. When I initially turn on AH it shoots up in the air again but if I bring the throttle way back I can almost get it to hover but it's still slowly climbing. I mounted the go-pro to the copter out boom 1 and will overlay some flight data so you can see what it's doing. Ill also upload the GPX files for you to check out. Josh
Josh When you turned it on what was your throttle position? If it was above center then check the setting in MKTools to make sure it isn't set at 127. Should be set to '0' from memory so that it sets at current throttle position.
anybody else having problems with the converter and 5S batteries? i have a Mk CS8 with 5s conversion and want to swap out only the BL's and PDB for castle ice 50 lites.
I did some flights in FL this last few days and was switching between the 5s and 6s batteries... I can tell you there is a big and noticeable difference in how the copter flys and reacts. The 6s is much smoother and much quicker to respond. The 5s feels more sluggish and isn't as stable. I could also hear a lot of variations in the motors even in just a hover when using the 5s batteries but it wasn't there in the 6s. My new 6s batteries just arrived and I will pretty much only be flying the 6s batteries from here on out unless I absolutely need to use the 5s because I don't have time to recharge. I should note that I just converted my FC to handle the 6s batteries by removing all the little caps and adding the two big 35V caps. I no longer am using the BEC which now allows me to have telemetry on the battery voltage. There is however a .6V difference from what the FC sees to what the battery actually is. I have compensated for this in the low voltage warning setting so it still goes off when it's supposed to. Josh
I figured that would be the case. I don't think 5s and 400kv is a good fit...not enough rpm for a stable smooth flight for a heavy multi running MK electronics. For me, the first indicator that your props weren't spinning fast enough was the uncontrolled left/right yawing.
Hi Josh, Nice to see it worked. Same voltage difference here > 0.7v. I dont think it's anything we can do about. So now you can even try 7s Fc software limitations is 7s max btw. Thijm
Matt I have my low voltage warning set to 22V in MK tools. This is about 3.6V per cell in reality. Josh
hello can you explane a little more what you do to convert mk fc to 6cell?? i dont understand what you have done? maybe some pictures? thanks
Hello Josh, With epic, 3515-400kv motors and 14x4.7 with 6s is not good ? Do I change the props ? I have plan using 15x10 apc. Please give me some advise.
No you should be ok with that. Ecalc says you should be ok. Only issue would be don't use the APC 14x4.7s. They are to flexible and you will have issues. You will want to use wooden or carbonfiber props with the heavier loads. Josh
Gary, that's interesting. I got this in an email from Ziggy. What do you think about this? "Make sure in ALT hold in the MKtool you are set for center stick 127 for vario, not auto. GPS hold is set to dynamic and your stick threashold is set to 8 or so. Double check your POTI and channels are set to their correct switches you want for GPS Hold and ALt hold"
I have tried it at 0, 127, and 100. At 100 it doesn't ascend nearly as fast as it does on 0 or 127. I will try a lower number next and see how that works out. Josh
Dave if you set 0 then the copter should hover at whatever throttle setting you are at when you turn it on. If you use 127 then when you turn it on you will need to pretty quickly move the throttle stick to the middle (127) position. That's why the Graupners have a centering spring. Use the spring if you use 127 or don't use the spring if you use 0. Josh something really sound wrong with the FC. Do you use the centering spring on the throttle? I think if you use the 127 setting it is the only reliable way to know where center is on the sticks. It would also need to be accurate by running a stick calibration on the Graupner. If you are using another brand of transmitter I'm not sure how they handle the centering. I've never seen a posting about any value other than 0 and 127. I would think that a 100 would need to then have the stick aligned with the 100 value equivalent (something less than mid point) on the throttle. You might be able to find that point by watching the channels in MKTools.
I don't think it's the FC... I have tried 2 FCs and both have the same result. I am using the MX20 but do not have the centering spring. Wondering if it's because of the throttle curve I have set? Ill try a lower number though next time out and see what happens. Just wondering, if AH doesn't work... what would happen in the event it goes to fail-safe? Josh
I used the MX-20 and had no spring and ran it with 127. In vario it would climb of sink slightly if I wasn't right at 127 when entering AH but it didn't jump up unless I had a big payload and was at hover around 60%. With the 5DIII that I mostly tested the converter with, it was spot on around mid stick. If you go into fail safe and you have use Vario selected in the fail safe AH setting I imagine you will keep going up or down. http://mikrokopter.de/ucwiki/en/MK-Parameter/Misc