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Old Feb 24, 2012, 08:59 AM
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I wonder if I need to order an Sk Powerbus.
I will be initially be using the 720 on my 6 s Logo 5003d with JR 8717's on the swash and an JR 8900 on the tail.
These are powerful, fast servos but I think that when I had the E T data logger on it the highest amperage draw from the servos was 3 amps. This was me flyin, I'm sure it has pulled more amps in the hands of my buddies.

I have read that the Sk S-Bus adapter for Futaba gear is only supplied w 3 volts. How do I increase that to avoid fail safe shutdowns?

My 8717's are not HV type and I run them on 6v. The 8900 tail servo is 4.8 and I use an in line step down. Are step downs OK with the Sk 720?
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Old Feb 24, 2012, 11:52 AM
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Lawrenceville, GA
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Quote:
Originally Posted by jamesppp View Post
I wonder if I need to order an Sk Powerbus.
I will be initially be using the 720 on my 6 s Logo 5003d with JR 8717's on the swash and an JR 8900 on the tail.
These are powerful, fast servos but I think that when I had the E T data logger on it the highest amperage draw from the servos was 3 amps. This was me flyin, I'm sure it has pulled more amps in the hands of my buddies.

I have read that the Sk S-Bus adapter for Futaba gear is only supplied w 3 volts. How do I increase that to avoid fail safe shutdowns?

My 8717's are not HV type and I run them on 6v. The 8900 tail servo is 4.8 and I use an in line step down. Are step downs OK with the Sk 720?
I use the powerbus on my Furion 6 (600) to reduce the number of cables going into the SK 720 and reduce vibrations.

Can't help with the S-Bus. I provide power to the SK 720, and servos, through the connections in the powerbus.

Rick
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Old Feb 24, 2012, 03:00 PM
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I use it the same reasons as above. Figured the designer knew best about lowering vibes to the unit. I would think the inline step down would be fine, hopefully others more knowledgeable will chime in here.
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Old Feb 24, 2012, 08:24 PM
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Rick, have you used the power bus on the smaller helis?
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Old Feb 25, 2012, 06:57 AM
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Originally Posted by jamesppp View Post
Rick, have you used the power bus on the smaller helis?
No. My smaller heli is a TRex 500, and there is not a lot of room in there. I have it mounted using the steel plate "sandwich", and vibrations are acceptable - self-leveling works.

Rick
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Old Feb 28, 2012, 12:01 AM
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Originally Posted by Ernie Mccracken View Post
It has probably been asked before, but can anyone compare the 720 to helicommand's HC3-SX? Auto leveling function (for use with electric 450's) is what I'm most interested in.
I own both and if you are "most interested in" Auto leveling then the helicommand's HC3-SX is the way to go !

Don't get me wrong Skookums 720 is a great fbl controller but you did say Auto Leveling was what your looking for and they both have this but there's def some prob's with the 720, it's far too sensitive to vibration to work reliably, if the vibration levels get too high the unit will kick the "self-leveling" off mid flight and you have no way of knowing this fact untill you hit the button only to find out it's unavailable to save your heli and by then you don't have a chance in heck to save it yourself, the only other way to know is if you haven't tried to use the "self-leveling" during the flight and landed and only then would you see the flashing red light indicating that the "self-leveling" had been disabled sometime during that flight ! Not Good !

oh and one more thing about the SK720 i did not like no matter how good you set it up is when you switch between modes (SL vs Non-SL) the baselines never match, by this i mean that you can have the heli setup with near hands off hovering with "self leveling" off and when you switch it on the heli with veer off in one direction or another or it could be the other way around, you could have it setup for near hands off hovering with "self-leveling" on and then switch it off and the same thing will happen the heli with veer off in one direction or another and the only way to stop this is to hold the stick in the opposite direction the hole time to counter this, i worked very hard for a long time to eliminate this and i could get it close but not eliminate it all together, the HC3-SX is seamless when switching between modes !

this is the samething this gentleman is talking about here......

Quote:
I did some test yesterday and it cannot be trimmed out mechanically. No amount of tilt on the swash to the right stops the behavior so it's the units interpretation of what is level and it will always go there. I tested arming it on perfectly flat surfaces and it's still there. The heli flies perfectly and the self level works great other than this weird drift to the left, but it's nothing that I can't deal with. The SL will still be fine as a bail out and that's all I use it for.
sir this prob is not your imagination it's a real prob that only happens with some 720, more with some than others and there is no fix as of this post date.

now after this post someone's going to say the the 720's SL works fine it just needs a heli to be in proper working order and that vibrations that are too high just means there something wrong with your heli and needs to be fixed or something along those lines, now if you buy into all that i can't help you, there WILL come a time much later when you realise you've been spending HALF you heli hobby time chasing vibration down, reading data viewer files looking for sources of vibration, trying various gels, tapes, straps, mods, and you'll think back to my post and think to your self "dang i should have listened to Chopper !"

now you have both sides of the coin and it's up to you to deside, good luck !
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Old Feb 28, 2012, 07:02 AM
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Quote:
Originally Posted by GetToDaChopper View Post
I own both and if you are "most interested in" Auto leveling then the helicommand's HC3-SX is the way to go !

Don't get me wrong Skookums 720 is a great fbl controller but you did say Auto Leveling was what your looking for and they both have this but there's def some prob's with the 720, it's far too sensitive to vibration to work reliably, if the vibration levels get too high the unit will kick the "self-leveling" off mid flight and you have no way of knowing this fact untill you hit the button only to find out it's unavailable to save your heli and by then you don't have a chance in heck to save it yourself, the only other way to know is if you haven't tried to use the "self-leveling" during the flight and landed and only then would you see the flashing red light indicating that the "self-leveling" had been disabled sometime during that flight ! Not Good !

oh and one more thing about the SK720 i did not like no matter how good you set it up is when you switch between modes (SL vs Non-SL) the baselines never match, by this i mean that you can have the heli setup with near hands off hovering with "self leveling" off and when you switch it on the heli with veer off in one direction or another or it could be the other way around, you could have it setup for near hands off hovering with "self-leveling" on and then switch it off and the same thing will happen the heli with veer off in one direction or another and the only way to stop this is to hold the stick in the opposite direction the hole time to counter this, i worked very hard for a long time to eliminate this and i could get it close but not eliminate it all together, the HC3-SX is seamless when switching between modes !

this is the samething this gentleman is talking about here......



sir this prob is not your imagination it's a real prob that only happens with some 720, more with some than others and there is no fix as of this post date.

now after this post someone's going to say the the 720's SL works fine it just needs a heli to be in proper working order and that vibrations that are too high just means there something wrong with your heli and needs to be fixed or something along those lines, now if you buy into all that i can't help you, there WILL come a time much later when you realise you've been spending HALF you heli hobby time chasing vibration down, reading data viewer files looking for sources of vibration, trying various gels, tapes, straps, mods, and you'll think back to my post and think to your self "dang i should have listened to Chopper !"

now you have both sides of the coin and it's up to you to deside, good luck !
Sounds like a fair assessment from someone who has experience with both. I am the one who wrote the paragraph you quoted, so it is interesting to me to hear that you share similar experiences with the unit.

I love it so far, but you are correct in that I cannot get both non auto level and auto level flights to be the same when switching between the two. That's no problem for someone who may want to fly in auto level mode all of the time in a scale heli for example. I still get a drift to the left when switching into AL, but it's not a hard drift. As long as I have altitude the bailout will work as needed as I only need a second or so to get back into control and a left drift is no problem as i get re oriented. Low to the ground or in between objects may be a different story though.
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Old Feb 28, 2012, 09:35 AM
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First, I am 100 % electric, and vibrations are manageable. My S/L works.

There is a fix for this problem in process. Stay tuned.

Rick
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Old Feb 28, 2012, 10:59 AM
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I think you might be refering to skookums next firmware that will include in the PC software the option for end users to be able to zero the accelerometers, it sounds like it could be the fix for the 2nd prob i talked about but the thing that upsets me is they had that ability from the start and when asked about the end user being able to do this themselves i was told that it wasn't possible because it requires an elaborate "spin table" and "special equipment" to re-calibrate the accelerometers so when i needed a new case guess what it had to be shiped to skookum and when when i was having the 2nd prob guess what it had to be shiped to skookum (which only made the 2nd prob only slightly better) and the list go's on and on.

and sure vibrations are manageable on most if not all electric helis but the point i'm trying to make here is with the HeliCommand HC3-SX managing vibrations is now a thing of the past, no more heli run ups or short test fights then running home to fire up the computer, hooking up the 720, downloading log files, running log file to check for vibration on the data viewer (which you have to pay more for pro ver) only to find out that everything was good except for one or two spikes that when over 7.0 which means the self-leveling would have kicked off unexpectedly had i used it during that flight, with the HC3-SX it could care less about vibration and the self-leveling NEVER kicks off for any reason ! and theres no special vibration pads, tapes, gels, steel plates or anything else needed for electric helis just one thin pad and for nitro just one thicker pad and thats it.

i finally got fed up with all that and broke down and bought a HeliCommand HC3-SX when i had seen them on sale for $440.00 and i got to tell you it was the best money i ever spent, i could go on and on about it but i'll just say this, this thing just plane works every time without fail !
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Old Feb 28, 2012, 11:45 AM
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Quote:
Originally Posted by GetToDaChopper View Post
I think you might be refering to skookums next firmware that will include in the PC software the option for end users to be able to zero the accelerometers, it sounds like it could be the fix for the 2nd prob i talked about but the thing that upsets me is they had that ability from the start and when asked about the end user being able to do this themselves i was told that it wasn't possible because it requires an elaborate "spin table" and "special equipment" to re-calibrate the accelerometers so when i needed a new case guess what it had to be shiped to skookum and when when i was having the 2nd prob guess what it had to be shiped to skookum (which only made the 2nd prob only slightly better) and the list go's on and on.

and sure vibrations are manageable on most if not all electric helis but the point i'm trying to make here is with the HeliCommand HC3-SX managing vibrations is now a thing of the past, no more heli run ups or short test fights then running home to fire up the computer, hooking up the 720, downloading log files, running log file to check for vibration on the data viewer (which you have to pay more for pro ver) only to find out that everything was good except for one or two spikes that when over 7.0 which means the self-leveling would have kicked off unexpectedly had i used it during that flight, with the HC3-SX it could care less about vibration and the self-leveling NEVER kicks off for any reason ! and theres no special vibration pads, tapes, gels, steel plates or anything else needed for electric helis just one thin pad and for nitro just one thicker pad and thats it.

i finally got fed up with all that and broke down and bought a HeliCommand HC3-SX when i had seen them on sale for $440.00 and i got to tell you it was the best money i ever spent, i could go on and on about it but i'll just say this, this thing just plane works every time without fail !
I'm glad to hear that it worked for you.

The GyroBot re-calibrated every time you powered up - I intend to follow up with Art about that.

Rick
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Old Feb 28, 2012, 12:44 PM
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if the GyroBot is re-calibrated every time you powered up how do you make sure it's perf level everytime ?

this is what art said about the zero cal......


Quote:
The reason for the feature is that we found that many mems sensor's zero point can shift slightly with age. It took a while to confirm, but we think end users can re-trim it themselves and get good results. There is some risk of misuse of the feature, but we're trusting the user rather than requiring them to ship it back.

For a level surface, what we recommend is to use a flat cutting board or similar object, and level it using a bubble level and shims. Then you can hold the unit flat on that.
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Old Feb 29, 2012, 09:02 AM
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Originally Posted by GetToDaChopper View Post
if the GyroBot is re-calibrated every time you powered up how do you make sure it's perf level everytime ?

this is what art said about the zero cal......
Why is perfectly level necessary?

What if it is off by a few degrees?

Will it zoom away? Probably not.

Rick
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Old Feb 29, 2012, 09:25 AM
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well i guess nothing's perfect........

Nothing's Perfect (3 min 38 sec)
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Old Mar 01, 2012, 02:29 AM
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I did notice my old helicopter with the SK360 would drifting off to the side after a crash. I found the tray the SK360 sat on was bent a few degree's. After leveling the tray it flew fine again.
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Old Mar 02, 2012, 02:25 PM
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Rick,
I am getting close finishing up the Sk720 install and setup on my Logo5003D.
It took a while for the power bus wiring to click in my abused brain but it is all wired up. I haven't prettied the wiring up yet .
I think I'm going to start with a set of rotor tech 560 mm blades. I'm picking up a little FLYBAR holding jig this afternoon so I can set my pitch easier. I have 90'ed the swash servo arms in the Sk unit and will pull the head and mechanically 0 the swash, reinstall everything and set 12 degrees +- and finish the tail setup wizard.

I'm thinking that for now, I will set my swash1, tail 1 bank and swash2 , tail 2 banks up exactly the same way only I will enable self leveling in the 2 bank. Does that make sense? This way everything should fly the same other than having the SL Feature.
Should I select upright and inverted SL as my only SL mode or will this do funny things during normal upright flight. It shouldn't unless I an in SL mode, right?
I got a bit frustrated about the wiring and not knowing about the S bus adapter and Power bus but I have enjoyed the learning process of my firstcFBL setup so far.
I just hope I don't mess something up and trash the heli right off the bat.

Edit: I have it ready to test fly. It was a little windy and I used that as an excuse to not try it out.

I do not have SL enabled and both banks are set up the same.

Everything moves in the correct direction
The info on turning off the Sk Gov and using the kontronic ESC gov was a little thin. I didnt have the throttle endpoints set as I reset the model completly. Also I didnt initially Reverse my throttle channel(Futaba thing) since I reversed all other channels that needed it in the Sk software. Then my ESC wouldnt arm...I tried everything I could think of ..Finally I reversed it and Turned the Sk Gov off (I had it set to electric) and bingo..it armed. I thought I would wait till tomorrow to try it out in case I remember something that I could have forgotten that will destroy my heli
Other than not knowing that I needed a Futaba S Bus adapter, an Sk Power Bus anda phase sensor (if I want to use the Sk Gov..I have an Eagle Tree one but may try that later, There is a lot of info out there on the Sk stuff. It was hard for me to remember everything. The Wizards were great but the throttle wiz..really didnt tell me how to set the enpoints. Yes, the buttons are there on the computer screen to push, but I thought they were only for setting up the SK gov.

It was probably more difficult for me than it would be for most heli guys..Im not sure but it will be an easy deal the next time. If it works as well as I hope. I have just the place to mount a couple more of them

Maybe Ill get the nerve to put it inb the air tomorrow
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