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Old Jun 24, 2014, 11:02 PM
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Just did a few test hovers with my RJX X600EP using the Robird and a Promodeler rudder servo. I had very nearly perfect CW and CCW piro stops with default settings.
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Old Jun 30, 2014, 02:30 PM
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Which PM servo are you using, Atomic? Is it the coreless or brushless?
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Old Jul 03, 2014, 02:42 PM
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Originally Posted by Dr.M View Post
Which PM servo are you using, Atomic? Is it the coreless or brushless?
Coreless. I think part of it is just the tail geometry of the helicopter though. Usually you have to soften the CCW brake or increase the CW brake but in this case the default setting worked fine.
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Last edited by Atomic Skull; Jul 03, 2014 at 02:47 PM.
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Old Jul 05, 2014, 04:31 PM
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Here's how I have it installed btw.







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Old Jul 05, 2014, 05:48 PM
as much as I can
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Very nice! 👍
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Old Jul 10, 2014, 06:18 PM
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Does anyone know what the srx cable actually is?
is is identical to this
http://www.hobbyking.com/hobbyking/s...ion_cable.html
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Old Jul 13, 2014, 08:48 AM
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Originally Posted by deonjams View Post
Hello Scott

Had an interesting problem today, potentially catastrophic, but luckily just minor damage on my new 550 clone (Hobbyking 550 FBL TT). Need your experienced input before I fly this one again. DX8, Robird G31 FBL system fitted with one Orange satellite, no receiver, Hobbywing Funfly 100A esc.

First ran up slowly testing all functions, then ran up to about 40% throttle. Still on ground after 4 minutes of spinning, all seems normal, moving rudder side to side to check responses, when suddenly it takes off straight up (means the gyros are working - one good thing). Closed throttle as in normal mode (and not TH as this could cause it to come straight down with -10 pitch), and only after about 2 seconds (could have been shorter, but when things are going wrong seems like an eternity) does it slow down, and as I stand there in a shocked and frozen state, it ends up in a tree where it hung until I got a ladder to remove it (thus the "minor" damage - blades, canopy, landing skid, main and tail shafts, tail boom, all damaged from hitting the tree). What could have caused this? I replaced all the servo snap links as they were really poor quality, as one failed even before spinning up the motor (servo moved on powering up and it snapped...), but even if this failed the heli would stay down (and probably tilt and have a blade strike). It went straight up, as if full pitch was given, no increase in motor speed noticed (as would be the case if F mode was switched by accident). Pitch setup for testing in normal is mild (35-70%), definitely did not touch any switches. There was quite a bit of vibration even present without blades (the main gear was oval, but for initial testing thought it ok while waiting for spares to arrive)

I do remember it going full pitch without input once during setting up, but I could not replicate the incident. Any comments would be appreciated.
More than a year ago I posted above in this thread, thinking it was the Robird that may be a problem in this setup. This heli today for the 1st time was succesfully flown, after the above and many more incidents. I had stored it and built other big helis to gain experience, and those were all successfully maidened, now went back to this one. Last week it had the same symptoms as the first flights - when spooling up the tail does not move. Thought it then either FBL controller or servo, or combo of above. It was only now that I have some savvy of the issues and seeing the tail stuck at speed that I realised I had a tail problem - probably a thrust bearing assembly issue in the tail (still to be checked - will pull apart tomorrow). Installed a new Align 550 tail blade holder assembly and it took off and controlled perfectly, to immense satisfaction. For those who might learn from this painful experience, and now easy with hindsight to see what had happened, let me show log of changes to fix issue:

- maiden flight - heli suddenly took off at full pitch. Initial setup was just Robird with one satellite. Core reason was brownout due to tail jameed causing tail servo to jam, abnormal current draw and bec could not handle it (only now I figured it out). My solution then - fit receiver with 2 sats, stronger tail servo, separate stronger bec and capacitor
- Tried flying again. No brownout this time but tail wagged badly, and gain up or down could not improve it. Thought it the FBL controller and changed to KDS EBar which I had spare, same bad tail control, and then smashed tail again (KDS Ebar does not return to neutral and it was leaning on the vertical fin which shattered and tail hit ground HARD. HK tail poor tolerances so fitted a KDE precision tail slider. Also found the main bearings really poor notchy quality so replaced these, tail shaft bearings and from and rear TT bearings. Also decided to take no more chances with controller, so fitted very familiar to me 7200bx with Spektrum tail servo. Can't go wrong I thought
- Smooth spool up and but still erratic tail control. Exasperated so I kept on landing and lifting off as had some control, expecting it to get better. Last minute of flying with poor tail behaviour when it suddenly spins far enough to unsettle me and overcontrol on the swash makes the heli come down a bit hard and a boom strike kills the boom, main blades and all the TT gears from the main gear back.
- Rebuild carefully especially tail (did not check tail blade holders...), fitted a Rotorstar RS-567MGT HV servo, only reading later that this servo may be a problem (Beenfly'n posted a failure he had, and there were other failure comments too). Same sticky tail, but back to the original tail slider didn't move when spooled up scenario. Moved fine if blades not turning. Penny dropped - it must be the thrust bearings!
- Changed tail blade holders and all ok using 7200bx, even with that suspect tail servo. It has held up for a full 6 minute flight but now could see that a 25C battery suffers with this setup - puffed up and warm. Needs to probably be at least 35C and higher.

Sorry about the long post, but this was such a frustrating experience but now rewarding outcome, I had to share it. The clone flies extremely well. Bottom line - Robird should be fine and will now use in other applications. Many things can cause issues and once one has more experience (especially as not many fly here to help resolve), it helps to problem solve better. Eventually...
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Old Jul 13, 2014, 05:19 PM
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Originally Posted by scribble007 View Post
Does anyone know what the srx cable actually is?
is is identical to this
http://www.hobbyking.com/hobbyking/s...ion_cable.html
No it's not identical it's a 2 in 1 adapter for sbus and sats where Tarot has separate adapters for each. It can also be used to provide power to the gyro when using a sat by plugging a power lead into the sbus port on the adapter.

The SRX adapter inverts the sbus signal and the ZYX sbus adapter does the same thing so it will work. The reason it needs this is because sbus uses inverted serial data and the Robird can't read an upside-down signal. I'm not exactly sure what it does with the sat signal. I think it just converts the signal voltage level from 3.3v to 5v but I've been told the ZYX sat adapter will also work. The Tarot adapters are less bulky than the SRX adapter and can be useful on smaller helicopters.

Don't over pay for those Tarot adapters, I've seen places selling those for $15-$20 but you shouldn't pay more than $5.
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Old Jul 13, 2014, 07:28 PM
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(double post)
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Old Jul 14, 2014, 02:00 PM
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Originally Posted by Atomic Skull View Post
No it's not identical it's a 2 in 1 adapter for sbus and sats where Tarot has separate adapters for each. It can also be used to provide power to the gyro when using a sat by plugging a power lead into the sbus port on the adapter.

The SRX adapter inverts the sbus signal and the ZYX sbus adapter does the same thing so it will work. The reason it needs this is because sbus uses inverted serial data and the Robird can't read an upside-down signal. I'm not exactly sure what it does with the sat signal. I think it just converts the signal voltage level from 3.3v to 5v but I've been told the ZYX sat adapter will also work. The Tarot adapters are less bulky than the SRX adapter and can be useful on smaller helicopters.

Don't over pay for those Tarot adapters, I've seen places selling those for $15-$20 but you shouldn't pay more than $5.
Thanks!
I actually have a spare one. I Need an sbus inverter for the frsky to minimosd thing.
Wanted to see if it would work before I bought one.
Thanks for your help
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