the story so far..... 

i bought this flysky 9x system and then before finishing building my quad i fried the 9x with reverse battery polarity ( novice me!! ).... it just went kaput!!!  ( well hatsoff to me.... you don't get a liftoff without the burning ) 

then i searched RCINDIA and also RCGROUPS and with a lot of information i bought the replacement objects (VR, Transistor etc.) and replaced the required parts. now the flysky 9x was glowing like a baby.... :-) i am happy and felt would be happy every after 

but the story continued.... the TX module behind the transmitter had to undergo some replacement too.

i now have KK2.0 board on the quad and when i check the RECEIVER TEST i see the numbers are flapping.... not much but when i bring it to ZERO after trying to fly the quad is very unstable with or without self levelling. i have reset all the Gyros and they all repsonded OK!!!

going back to the receiver test all those which were set to ZERO i see them flapping either 1 or 2 positions in + or - 

will replacing the RF module with the FrSky DJT 2.4Ghz Combo Pack for JR w/ Telemetry Module & V8FR-II RX help me make the aircraft stable?? is the current Flysky RF module the main culprit?

and finally where can i get FrSky DJT 2.4Ghz Combo Pack for JR w/ Telemetry Module & V8FR-II RX?

It could be because of the module but most likely you have some interference from the positive/negative line in the ppm line. try shielding it and see results...also check your pots once, and any solder bridges

hi girish,

thank you for the reply. could you please put some light on the +/- line in the PPM ( could not understand it that is a setting of the TX or something on the board?? )

and yes which POTS?? there are three pot dials on the TX but to my knowledge those are not in use.

your help in this matter is highly appreciable.....

Sorry chief, my answer was convoluted. I was confused myself when I read again! 

What I meant was, there seems to be interference in ppm from the +5v or Gnd wires. It could be a shortcircuited somewhere (maybe a solder bridge) or noise from the VR that's causing this. Can you also check the capacitor on the in and out of the VRs, are the alive and kicking?

GS

hi girish,

do you recommend dumping the TX and going in for a new one?? instead of fighting on this...??

saint - have you tested tx with a servo ??

Partner, my recommendation would be of little use. There are other factors that might drive your decision much better, including your willingness to fix it, your budget, and most importantly peace of mind...I can figure out you're not too happy about the last set of repairs..so ditch it if it ain't working out. The last thing you want is your plane in air and repair woes knocking your mind out of breath

The 9x is an ugly duckling. You've already given it the FrSky kit, so it's almost a swan. Give a last try to fix it, if it doesn't work out, salvage it.

GS

PS: You said that the numbers are jumping, how bad is the jump. I am not a quad guy so can't comment, but a minor swiggle shouldn't affect much. Do servos jitter when you hook it up under no load? Is this on all channels or just one? If one, which one?

Yes in the kk2.0 receiver test menu, the numbers may not remain constant all the time, there is a movement of 1 or 2 points. I have the same issue with HK 6ch tx and now Fly Sky 9ch, but doesnt affect flight much. Think its due to the springs attached to the sticks.

So I think your tx is working good, maybe you need to tune kk2.0
But you can go for Frsky upgrade, you will have better strong range and peace of mind!

i would say do not trust on repaired electronics when it comes to flying a quad please,
i would advise you to keep the current tx aside and go for any new one , enjoy.

meanwhile your can do experiment on your current tx with out risking your expensive quad copter , it can be fixed to 100 percent with good guidance , there are many guys on forum like mr girish who have a good knowledge of electronics .

That (+1+2/-1-2) jump in kk2 rx test is normal if your tx sticks do not center correctly(there will be some play, keep it next to futaba/etc and see) many flysky tx stick do not center well, even with this defect, flying quads and planes should not be a problem, symptoms- with planes the servos might chatter and quads will drift.
My 9xr had same problem but i changed both gimbal stick set of it with new ones.
your radiolink is not responsible for this, but still- frsky.

YOU CAN BUY IT FROM HERE...

You can check here for FrSky DJT 2.4Ghz Combo Pack for JR w/ Telemetry Module & V8FR-II RX.....

http://www.rcproduct.in/frsky-accst-module-india/11-frsky-djt-24ghz-combo-pack-for-jr-w-telemetry-module-v8fr-ii-rx.html

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