Mick, check your PMs. I sent ya one.

9116 Transmitter Stick Potentiometers

Those carbon film potentiometers like to have current flowing through the wiper (center connection) instead of operating as a high resistance voltage divider..

Suggest putting 10k resistors from the outer terminals to the center. It won't add current at the center, but will make the places where the potentiometer lose contact look like center stick instead of infinity. As the wiper is moved to the ends, there will be added current and possibly keep the wiper clean.

It will change stick linearity and will have to be tested.

On older V911 transmitters, resistors are added to change the center (mid stick) to have reduced control (exponential).

Forget above. The problem is the encoding, not the potentiometer. The dead spot begins and ends at the same value, it should be different. As if there is a severe exponential at center stick which can only be done by the encoder.

4 flights into my new tail motor and it is toast.The electrical smell tells all.Is it possible a bum board may be burning these out quickly.I have the tx set for defaults(per Micks blog), and set to slow.

Originally Posted by Jasen40

4 flights into my new tail motor and it is toast.The electrical smell tells all.Is it possible a bum board may be burning these out quickly.I have the tx set for defaults(per Micks blog), and set to slow.

Could also be stalling the motor that burns it out. Like taking off or landing in grass that stops the tail motor from spinning, or not killing throttle before crashing.

Originally Posted by stormforce

Ok Guys (and gals if they are lurking in the background).

Here's my weekend project finished, a fold-able and easily transportable "landing platform", that I think I mentioned a few pages ago, in reply to mikefromgermany I think (where are you, bud???).

Sorry mate,

With a newborn child time is a main factor...

A short summary:
first flights with the 9116 absolved - first crashes involved - damages so far:
1. inevitable flybar strikes in canopy and tail pipe
2. crashed in railroad-tracks 100m away (stock-battery suddenly gave up...) - main shaft bent, rotor head pins sheared off, flybar bent beyond recognition

Makeover session finished, minor improvements I made:

1. installed Low Voltage Buzzer (2.50 €) under bottom plate, weights only 6 gr and it indicates per LED and sound if voltage per cell is dropping below 3.6V. Plus: balancer plug is secured.... (Pic1) As stated often enough before: Highly recommended!


2. 800mAh 30C LiPo-Pack mounted

3. spacer (2mm thick plastic) for the left canopy-mount (Pic2) – gained free servo-travel


4. washers for main blade grip, stamped from 0,15mm thick plastic sheet – outer diameter 9mm, inner diameter 4,5mm (Pic3) – now better, direct steering performance, blades don’t wobble around any more but are still movable in the grip.


5. shortened main shaft to 73mm – so the reinforced Rotor head (below) fits

6. Rotor Head makeover: I replaced the 2 sheared off blade pivot pins by a single brass bar, 2,4x20mm and reinforced the upper part of the rotor head with a glued in steel rod 2,0x10mm. (Pic4)



Someone asked for measures earlier on: Inner reinforcement for standard rotor head shaft (without my pivot pin-replacement) should be 2,0x20mm for a perfect fit.

My 9116 is now performing quite well.
Hovering backwards is in comparision to forward extremely slow. Is that regular behaviour? It was the same out of the box. I levelled the swashplate, made the mechanical trim, it stays nearly hands-free in mid-air. My Xiedas are as fast backwards to FF....

Any suggestions?

Mike

(BTW, my fleet is growing.... 1 x 9116, 3 x Xieda 9958 ....)

Welcome back,

How do you find the time to do all those mods, when I thought you'd be catching up on some sleep, with the new born around.

Great mods too. In regards to the forwards / backwards movement, if you favor forwards on the swashplate, backwards flight suffers and visa-versa.

How did you like the 9958's with the standard flybar against the mSR flybar? I like the mSR flybar better for quicker cyclic response.

Originally Posted by Jan_onewish

Thank you, I resolder it and now it is ok. The problem is that resistance value is linear as I move stick (now, when I moved green pot to left stick I dont have dead spot on throttle) so all pot are 100%. Before I wrong soldered it, problem with juping throttle was present.

Mick, look at the last video I uploded (around 1:12 min). As i moved stick forward, RPM on heli starts to jump (I measured resistance of pot in that position and it is normal and linear) so because of that I think it is bad PCB

Hi!
I managed to solve my problem with tx. Today, I took tx apart and connected precise digital 5k(502) pot to PCB. I found out that for some reason PCB thinks that throttle is 0% when input voltage from pot is 0V and 100% when voltage 0.815V ( on default it should be 100%, 3.3V) so I used digital 503 pot wich I put between pozitive input voltage from PCB and pozitive input pin for pot and set pot to around 24k ohm resistance (I just lovered input voltage on throttle pot to 0.815V and preserve linearity). If PCB again change required voltage for 100% throttle I will just readjust digital pot with a screwdriver. I have tested it on heli and respond is very linear without any RPM jump or dead zone.
Thank you very much for your help.

well, done !!!

Your diagnostic skills are highly commendable.

I think you get the award for the most innovative solution to what seems to be a common problem.

Originally Posted by Jan_onewish

Hi!
I managed to solve my problem with tx. Today, I took tx apart and connected precise digital 5k(502) pot to PCB. I found out that for some reason PCB thinks that throttle is 0% when input voltage from pot is 0V and 100% when voltage 0.815V ( on default it should be 100%, 3.3V) so I used digital 503 pot wich I put between pozitive input voltage from PCB and pozitive input pin for pot and set pot to around 24k ohm resistance (I just lovered input voltage on throttle pot to 0.815V and preserve linearity). If PCB again change required voltage for 100% throttle I will just readjust digital pot with a screwdriver. I have tested it on heli and respond is very linear without any RPM jump or dead zone.
Thank you very much for your help.

Great thinking and excellent solution Jan_onewish!

so I used digital 503 pot wich I put between pozitive input voltage from PCB and pozitive input pin for pot and set pot to around 24k ohm resistance

Very interesting work! I would love to see a good shot of this 503 pot and what it looks like on the front of your tx.

Originally Posted by rexless

Very interesting work! I would love to see a good shot of this 503 pot and what it looks like on the front of your tx.

Thank you for nice words!
I have been flying all day and it is blast: heli responds very nice and it seems that this mod is working.
503 pot is common pot on ebay
http://www.ebay.com/itm/2-x-50K-OHM-...item3a6806d14a
You can also find it in a set of pots on ebay.
When I turn tx on, move stick to max, I have only few bars on LCD. When I go in menu and do do same, I have all bars (heli respond the same way as bars when menu on tx is opened).

Wow! I sure am glad mine worked as designed right out of the box!

Hello Forum!

New user with what I hope is a simple problem - haven't been able to find solution through searching this thread (very long thread). Any help with troubleshooting would be great.

DH 9116 came configured for Mode 2. Everything works fine in Mode 1 but I have a servo throw problem in Mode 2 for operation of ELEV.

When throwing the elevator into full forward only the right servo (looking at the 9116 from the rear) kicks up to move the swash-plate. Servo on the left sits at center value and is unresponsive, causing the swash-plate to angle forward with a considerable lean. I can manually over-ride it if I push the elevator/aileron stick towards the upper right corner but it just doesn’t feel right.

Backwards operation of elevator works fine pulling the elev/aile stick straight back; swash-plate is evenly situated with a backward angle but not vice versa.

Almost seems as if the transmitter isn’t properly linking both servos for forward flight? Like I said, works fine in Mode 1 but I prefer Mode 2.

Any help would be greatly appreciated. And also – sorry if this has come up before, tried my best to search the forum but no luck.

-T

Originally Posted by Jan_onewish

Thank you for nice words!
I have been flying all day and it is blast: heli responds very nice and it seems that this mod is working.
503 pot is common pot on ebay
http://www.ebay.com/itm/2-x-50K-OHM-...item3a6806d14a
You can also find it in a set of pots on ebay.
When I turn tx on, move stick to max, I have only few bars on LCD. When I go in menu and do do same, I have all bars (heli respond the same way as bars when menu on tx is opened).

I'm trying to wrap my head around why you get full throttle at a display of only 4 bars. For some reason I had imagined you had replaced the ?sensors? on the side of the sticks... or if you did maybe I'm just not understanding how this works. I'm still a green n00b with this RC stuff but I love figuring stuff out. Thanks so much for posting the photos and the link to the ebay seller! I don't think I have the same problem but I have another 9116 sitting here, unopened so you never know...

Which reminds me, today I flew my 9116 which I've been having some trouble with. I had a new vibration last week so I checked the balance bar and straightened it out. Eyeballing it, it seems like it's within 1% tolerance of straight. I still had vibration so I tried replacing the blades and checking all the screws. Seems like it's all good. I had a light breeze today after a week of wind & rain so I gave it a try in the field but it's acting very strange. Someone had suggested my OEM battery is fubar and I think that makes sense. Sometimes the controls seem unresponsive. I can try and spin and nothing seems to happen. I can push forward and nothing happens. Then it's like slowly it decides to push and away it goes.

I'm going to try a battery I have here from an F45 and see what happens.
Thanks all for the tips and suggestions an all the mod info you post. Us n00bs are learning a lot and realizing there's way more potential to these little beasts than we may have realized when we picked them up.

Still got 9116 in the #1 spot on shelve battered but still flying. Fly the MJX F45 and the Honeybee a lot but usually take the 9116 along cause on my worst day I can still handle it and we have had many happy moments together.