RC India

I am a complete noob to RC ( the most experience I had was a few chuck gliders and control line planes). After doing an edX course on Autonomous Navigation for Flying Robots, I became obsessed with quadcopters. I finally decided to build one since I don't have the space or regular transport to get to a flying field for planes. I did a lot of reading and ordered a Reptile 500 Kit from quadkopters.com this Tuesday and received it today in perfect condition. The quadkopters team was extremely helpful and answered all my doubts. I unpacked all my stuff today since I also received a package from RCmumbai and picked up some stuff from RCBazaar. I am waiting for a charger power supply from Indian.Hobby.Shop but I will try to post a build log (of sorts) soon. For now, here is my setup:
Reptile 500 frame (clone of TBS Discovery)
Sunnysky 2212 980 kV motors
SimonK 30A quadkopters ESCs
kk 2.1 board
Wolfpack 2200 mAh 25C and Wild Scorpion 3500 mAh 30C
Avionic RCB6i

Kudos to RCBazaar, QuadKopters and RCMumbai who have made this possible. Thanks also to Mr. Bhavesh from Indian.Hobby.Shop who called to answer my doubt within 15 minutes. I am very happy with all these stores. This a long post and I will wind up by saying that any tips, suggestions or advice will be greatly appreciated.
Siddharth

Good luck, all parts seem good

I just completed d same kit ,from quadkopters ,its great,d kit is awesome, and highly stable, just make sure u have space 2 mount d battery before u start wiring d stuff up ,  careful during ur first flight d quad is very powerful , with minimum throttle it just zooms up , I ended up breaking a prop , make sure u use thread lock 2 lock d props in  :thumbsup: , good luck

Thanks a lot guys. I was very impressed with this combo in particular since the kit included the frame, motors, ESCs, the flight controller, props and all accessories at the impressive price of Rs 9500. I have started my build by mounting the prop adapters to the motors (using a drop of Anabond Blue on each screw) and soldering bullet connectors to the ESCs. I also attached the top plate of the frame (again using a little Anabond on each screw). How do I post photos? The fie size is over an MB each?

First make d power distribution cable , then mount escs , then connect it 2 ur pwd , then mount d motors, then hook up ur escs 2 d motor, then connect kk board ,after u confirm d direction of d motors. , calibrate ur escs , then mount d props ...

Thanks. I am having a bit of trouble soldering to the power distribution board since the 50W soldering iron I got was faulty and I am stuck with a 25W one. I have already assembled the upper half of the frame and mounted the motors.

go to sp road n get a Solderon Brand soldering gun. this is really a really good one. also use a lot of flux while soldering the PDB this ll help u out.

Still suffering with the PDB. I will try to pick up a new iron this afternoon or make my own wiring harness (in the worst case scenario)

trouble soldering ?
Well first clean your Iron tip.
then heat the parts to be soldered with the iron
heat it together for enough time apply lead from a side, it should flow evenly to make a perfect joint - in this meathode no flux required - the joint will be perfect
Btw, are you soldering ESC wire to PDB or gold connector ?

I am soldering the power wires to the PDB. I think my soldering iron cools down the moment i touch it to the board and I get a lumpy cold solder joint. Do you think 25 Watts is enough for the job? I was also planning on soldering female bullet connectors to the board later. Any tips on how to go about it?
Thanks

well soldering wires is easier for a beginner.
25W is enough in normal condition - ensure you have enough supply voltage from mains.

1) first apply some rosin free flux to the wire and if needed to the PDB and heat it.
2) make sure solder tip is clean , and have a coating of lead on it (this is importent)
3) heat the wire and soldering pad together for few secs, and apply lead from one side, then the lead will flow to form the joint - apply enough lead.
If lead does not flow- heat is insufficient.

Btw to solder ur connectors to the escs u need , a pointed soldering tip ! , ND yeah  I had the same problem , 25volt solder will be really slow to heat up .., u need a more powerful one
 

Thanks guys. Looks like power is the problem here. The solder flows beautifully at first but when it touches the PDB it soldiifies instantly and no matter how long i touch the iron to it it does not melt again.

well, that is lack of skill :(
25W chisel tip (45 degree) soldering iron is enough for almost any common works.
no need of pointed tip, for soldering bullet connectors, first fix the connector vertically on something and place the iron tip to the small hole on one side of connector (here chisel tip is better than point tip) close that hole with soldering iron tip - heat for few secs, and apply lead from top - fill the connector with lead up to 75% now dip the wire to the Lead - the Iron is placed on the hole through out the process.
Now just move the wire up and down - for lead to enter the strands and make a perfect joint, take back soldering iron and allow the joint to cool.

first apply flux to your PDB, then make a thin layer of solder, and attempt again, .
25W is enough.
place the iron for the time needed for the lead to flow evenly- don't be frightened it won't damage anything.
is it first time ?

First time soldering 14 AWG wire and a PDB. I have soldered everything from resistors to ICs on protoboard earlier.

ya, me too had some problem with these wires, But I did make it beautifully with my low power iron.

you should first coat the wire tip and solder pad completely with lead - can't upload a video don't have cam now.
But it can be done .

Thanks for the tips. I coated the wire and pad with solder. The problem is that I can't melt it afterwards. Anyway, I will try again later.

now , there after coating wire and pad with solder, don't try to solder with that,
Now return to reply 10.

Oops looks like I misunderstood. i will try what you suggested  :thumbsup:. Meanwhile, I have been balancing my props.

the problem of solder quickly solidifies is because our Iron tip is small - but with some tweaks like this we can make it happen with any iron.
The first time, we may have to spend tens of minutes for a single joint, but once got the trick it's a breeze. :thumbsup:

yup, it's a good habbit always balancing new props, and after crash.

Bro very first look at the solder gun tip, if it has turned black then there is carbon deposition onto it. so it may pose problem in soldering. if u ve a sand paper then rub the tip, until all the carbon deposit is removed. also take some thick sponge dip it into water n place it over the solder gun stand. Keep your solder tip rubbing it over the sponge every time u solder a spot. this ll keep your tip clean. Also its better to get a branded iron rather than going for cheap alternatives. PS get a Solderon brand Iron its really good I am using this one since 3 years, n ve replaced only one tip so far. Moreover its not like I use it once in a while. I am an Electronics Professional, so I ve to use it almost all the time. The sponge technique ll help u a lot. Try it. The best way to solder is, take someones help, tell them to hole the wire onto the board itself, then apply some flux over the spot as well as to the wire to be soldered. hold the wire onto the board, then hold the lead in one hand n the gun in other hand n directly apply the lead to the spot, rather than applying it to the gun tip.

I have a Soldron iron and I am also using a Mr. Grippy Soldering jig so I don't need anyone to hold the wire  ;D. I will try what you guys have suggested and post soon.

:thumbsup:

Well in that case U might ve three hands. My Mistake to Suggest you.

 ;D Three hands. I was 'this' close to soldering it but it is just not working out. The solder is not bonding to the PDB and is not flowing I can't melt solder that I have already put on the wire :(. I am just going to get a more powerful soldering iron and try again. Meanwhile I mounted my ESCs to the frame using zip ties.

that's sad :(, but I use the same iron for any works.
well try with what you think is appropriate. :thumbsup:

Thanks for all your help. I will give it another shot when I am fresh in the morning. Otherwise I will get a different iron or use a pre soldered PDB like the Hobbyking one

I tried again and following the tips from Sooraj, I got the PDB soldered  :thanks:. While testing the setup, one motor was not spinning and would only pulse (spin once or twice) when I raised the throttle. I checked my PDB again and found a loose joint. After resoldering, during testing I appear to have destroyed one of the ESCs  :(. I am not completely sure how, though it could have been because of bad soldering or because I ran the motor at full RPM without a prop. Is there any way I can check the ESC or save it? I have decided to drop the PDB and use a wiring harness from quadkopters instead. I will need to order the harness and spare ESC and get back to this build.  :(

glad to here you did it .
there can be many issues for non spinning motor - it is not necessarily be bad soldering.
you can check this ESC and motor, by directly connecting the signal wire of ESC to throttle channel of receiver - the motor will respond to throttle stick movement, if ESC and motor are good.
There is no problem running a motor with out props on - it is always advised to tune and test your board only after all props unmounted.

one more thing, make sure you didn't reversed polarity of ESC power cables while soldering them to PDB.

I read on RCGroups that running the motor at full throttle without props can be harmful. I will try testing it how you described and get back to you.

Nope. One ESC is not working. It does not even power up the kk board or receiver when I connect. I will order a new one.

so it seams you burned it by soldering in reverse polarity - but as just a electronic circuit, I recommend you to rip off the heatshrink around ESC and look what is wrong in it (if you know what to do !!)

I have nothing to lose here  ;). I will check out the insides of the ESC.

I FIXED IT! The problem was so simple, I can hardly believe it. I removed the heat shrink and began checking continuity with my multimeter. There was no continuity between the positive input pad and the positive bullet connector! I cut off the connector, soldered a new one on, and the problem was fixed. Since I don't have 25 mm heat shrink, I wrapped the ESC in one layer of silver duct tape and put the original sticker back on  ;D. Sooraj, your advice has been really helpful  :thanks:

It's happy to hear everything is going fine :thumbsup:
Wish you perfect landing ;D.
Regards,
SPN

All systems are go!  ;D Ground testing is complete. All the motors are spinning in the right direction. I can hear the motors speed up while tilting in self level mode. PI gains are on default as of now. I will maiden the quad soon. Any tips for mounting the props and battery and for the first flight?

you have KK 2 board I think is that right ?

for any flight - mount the props tightly, check the prop adapers have strong fit to motor shaft.
Battery should be mounted secure, It should not come of while quad tilts. (I did this wrong !).
everything should be tight and flight controller should be level.

which is your FC board ?

You are right. I have the kk 2.1(.5?) that came with this kit. I have calibrated the ESCs and the accelerometer. Receiver test is also done and I reversed the necessary channels. I am using a smaller battery for the maiden- a Wolfpack 2200mAh, attached with a velcro strap. Later on, I will use the larger Wild Scorpion 3500 mAh. Just have to double check everything before the flight. What happened to your quad? Did the battery fall off?

sorry - I found you have KK 2.1 , well calibrate accelerometers, by placing the quad in level surface.

check the receiver signals on FCB

now check minimum and max ranges of each channel as picked up by flight control board. min value should be -100 t -90 and max. value should be 90 to 100 for each channels. If not adjust in transmitter by decreasing end points.
trim the transmitter channels to zero in middle position (as seen on FC board)
check response to stick movements - the LCD will display the movement while moving the sticks. I mean when you move roll stick to left, the LCD displays left in side of appropriate channel.

sorry - couldn't read your replay while posting the above ;D
my battery didn't come off but it hanged to  a side (deans connectors are strong !) , but that made lose of controll - but nothing worst happened as quad was in ground level

Wow that must have been scary  :o. Do you think the default PI values are OK:
P gain:250
P limit:100
I gain:250
I limit:20
Pitch and roll are linked. I will tune it later.

OMG ! - this is not default - better you noticed it- otherwise :banghead:

Roll/pitch P-tuning:

Set the gains and limits to the following values:

Roll/Pitch P-gain: 30 (For a small 25cm size set to 20)
Roll/Pitch P-limit: 100
Roll/Pitch I-gain: 0
Roll/Pitch I-limit: 20

Yaw P-gain: 50
Yaw P-limit: 20
Yaw I-gain: 0
Yaw I-limit: 10

Now, Increase Roll/Pitch P-gain by 10 (5 or less for a small aircraft) at a time, and test your aircraft response by hovering and move the left stick in short and fast movements.
As you increase the gain you will notice:

1: The aircraft reacts faster and feels more connected to the stick movement and wander less on its own.
2: The aircraft may oscillate for a short time. Usually a few oscillations, but may be more if gain is high. If it oscillates continually the gain is too high.
3: The aircraft may be harder to land, it bounces back when touching down.
4: The aircraft may climb.

When the aircraft has a good response and does not oscillate or climb when testing, P-gain is good.


Roll/pitch I-tuning:

1: Trim it level.
2: Fly fast forward and center the stick.

If it level itself, increase I-gain.
If it stays in attitude, I-gain is good.

Alternatively setting I gain to 50-100% of P-gain does the trick.


Yaw P-tuning

Increase Yaw P-gain by 10 (5 or less for a small aircraft) at a time, and test your aircraft response by hovering and move the Yaw control stick until it have

yawed about a quarter of a circle, and then center it.

As you increase the gain you will notice:

Or just for a quick maiden, reset your board to get default values, - I still fly with default values - no problem so far :thumbsup:

Thank you. Even I was wondering since they seemed very high. I am not sure why since I did a factory reset first. I followed the instructions in this video and changed the gains. http://www.youtube.com/watch?v=8NAXSBCtSLY#ws (http://www.youtube.com/watch?v=8NAXSBCtSLY#ws)

well if factory reset does not get these values as default, set it manualy and FLY!!
Default PI editor settings
Roll/Pitch Axis:
Pgain = 150
Plimit = 100
Igain = 50
Ilimit = 20
Yaw Axis:
Pgain = 150
Plimit = 20
Igain = 50
Ilimit = 10

I tried to take off but the quad is flipping. It appears that the back is too heavy. What do I need to do about this.

is the flipping happening with default PID ???

well I too had this flipping while take off - at first I thought it is a stick centering issue and compensated the flipping by stick movements while take off- but I was running old f/w at that time, yesterday flashed latest firmware- and now the quad is level in takeoff and there is a nice change in every attitude of it.

gonna upload video of my flights, stay tuned .

Could it be an issue with weight distribution? The back is quite heavy since it has the battery.

NO, my quad is not uniform in weight, even angles are not exactly 90 degree (my custom frame)

still I can fly with out any problem.

which is your KK firmware version?

Version 1.9S1 came pre loaded. My update tool is still shipping.

that is new firmware - but in my case, one update solved all my problems :)
but you can still fly the quad by compensating it's flipping through manual stick movements, it's little tricky, but it can be done. I mean, if quad flips backward, give a little forward pitch wile take off .
But if there is unwanted movement, once the quad is in air, immediately land it.

I am barely able to get it off the ground. it is really unstable and drifts a lot when I try to hover. If I increase throttle it flips. What do i do? As of now, I am charging the LiPo. I will try again later.

these were the same symptoms I had, broke 3 props, by flying withese conditions - but a firmware burning magically solved all my problems, nothing else !! . Now It won't drift even if I take hands from controls !!

watch my flight video - in HD .
www.youtube.com/watch?feature=player_detailpage&v=6FSuqgml5hI (http://)

you can see, the behavior of quad with perfect PI tuning in the end of video :)

Guess I will try one last time and then wait for my firmware update tool. Reflashing the firmware might help.

No wonder I was having so much trouble. My firmware is 1.9S1 when the latest is 1.19S1 (Btw, it looks like the .xx part follows an order like 1.10S1 after 1.9S1). I am 9 versions behind! The gyro may also be reversed since when I tilt the quad forward, the bubble moves back slightly. I am not going to risk flying until my programmer arrives.

:thumbsup:

No, that is normal . :)

Oh ok. I thought it might be a problem. Anyway it appears that the only issue now is old firmware. My PDB is also pretty ugly so I am replacing it with this harness: http://www.quadkopters.com/product/multirotor-accessories/xt60-to-4-x-3-5mm-bullet-power-breakout-cable/. (http://www.quadkopters.com/product/multirotor-accessories/xt60-to-4-x-3-5mm-bullet-power-breakout-cable/.) If I can get this quad to fly I have a lot of upgrades planned  ;D such as using an APM board with GPS.

KK2.0 itself performs best for me - APM is advanced, still you will love KK2 after correct tuning- !!

P.S when you upgrade count me in line to buy your old KK  !! ;D

You really are an opportunist  ;D. Arducopter was the first thing I read about in the field of multirotors and I always wanted one after watching this hilarious episode of Flite Test http://www.youtube.com/watch?v=4IJ2V8xVJO4#ws (http://www.youtube.com/watch?v=4IJ2V8xVJO4#ws) Anyway, the upgrade is at least a few months away. i need to get this quad in the air first and learn how to fly and plus the kk will be a great backup board even with an APM.

you caught me :(

Haha   :giggle: . It's time to put my quad away (at least for one or two days)  :(

you can't do that, you will understand gradually ;)

Success (a minor one)! Since I am too impatient to wait for the USBasp tool, I decided to flash my kk with the newest firmware using my Arduino Uno an an ISP. I followed the instructions here: http://blog.oscarliang.net/flash-kk20-16-firmware-upgrade-arduino/. (http://blog.oscarliang.net/flash-kk20-16-firmware-upgrade-arduino/.) SInce I have a Mac, I needed to make a few adjustments to the procedure. I will start a new thread on this topic.

Oscar liang's blog is a best place to start learning multirotors, he has so many tutorials ther, I learned a lot from it.
When using arduino as ISP, make sure you correctly connect vcc and ground to ISP port in KK board, if you are unsure by any means, just connect vcc and ground to ESC or receiver terminals, but don't worry oscar have done a nice job there, by marking pins of KK ISP header - You can only use terminal to flash using Arduino as ISP, KKflashtool can't be used :banghead: I don't know how it is done in mac.

I modified the procedure from my (average) knowledge of Mac. It is really not that difficult if you have been using Mac for a while (as I have). Check my new post here: http://www.rcindia.org/multirotors/updating-kk-firmware-with-an-arduino-(on-a-mac)/ (http://www.rcindia.org/multirotors/updating-kk-firmware-with-an-arduino-(on-a-mac)/)

so, have you test how new f/w performs ?
sorry- saw your reply on other thread - well no flying topic on other thread, ok ???

Good idea. Let's avoid confusing the other thread. A firmware update solved all my problems and I was finally able to get my quad in the air. What an amazing feeling! I had several rough landings and managed flight times of only 15-30 seconds (lack of space). I will go to one of the empty sites in my layout tomorrow and practise. I will also have to do some tuning. Does anyone know about any good simulator that has a quad (preferably for a Mac but Windows suggestion are fine too.)? I also found a good sim on the iOS app store and will try it out.

well why you need a sim ? - you are gonna fly a heli or what ???
flying a quadcopter is easy dude (once it is correctly set up ;D) .
just go to a open space without trees, and practice hovering the quad, don't get it to more than 3- 5 mts high, and also avoid testing the range of your radio ;D.
you can use those yellow smiley balls fitted to your landing skids, for dampening the effect of rude landings while practicing.

Wish you safe landing :)

You have lots of experience, so I will listen to you and not get a sim yet  :hatsoff:. I will practise tomorrow. Going to try and pick up some of those smiley balls. Should I hot glue the sponge balls to the landing skids? I am definitely not going to let the quad get more than 30 feet away from me. I just need to resist the urge to cut the throttle too much

well I can't agree with that - I have flying experience of only 3 days ;D , and it is 4 charge cycles of a 3S LiPo :giggle:.
But what I said is from experience gained in these mere 3 days !!

you can attach smiley balls to landing skid by any means - I didn't used it and learned it's need while practising ;D -

From all your help, I thought you have more experience. You definitely have excellent knowledge of multirotors. Speaking of your charge cycles, did you get a charger? Which one? I saw that you hadn't received a charger from another member even after a month. I am using a clone of the IMAX B6 and I am happy with it's capabilities. Which LiPo are you using?

You may laugh, while hearing this, but I am charging my LIPo using my PC SMPS !! (I managed to gt 12V o/p working in my burned SMPS board).
And yes, that guy cheated me :banghead: - lost 500 Rs. that was my first purchase through this forum :(
But I gained contact with so many good people through this forum :) so I am gonna forget this guy, a little sad though .
one helpful person (subash sir, :hatsoff:) have agreed to give me one simple Lipo charger for free!! , and more than that, he is also giving a LiPo and a Imax for some days use.

BTW , I use wolfpack 3S 2200mah LiPo - I bought two of these packs from anjan, I managed to damage one cell in a pack - so now have a 2S pack and a 3S pack.

Again, this just shows how good your DIY skills are  :hatsoff:. How do you balance your LiPos though? I have seen that the WolfPack 2200 mAh 25C LiPos have the best capacity to cost ratio.

It seems, it is self balancing with a error of approx .1 to .2 V , if it is more imbalanced, I charge the low voltage cell separately with a mobile charger.

expect some pics of your build  8-)

Here you go.

i managed some flying but my quad needs a lot of tuning. It tends to climb and dip rapidly. A prop fell off in mid air and I lost the mounting nut. I will go check in a hardware store for one and fly again later.

for the first problem (climb and dip on small throttle variation) - you should set a throttle curve - which goes smoothly after the hovering point to up to 70% throttle on your Tx.

you know what these prop adapters sucks - I lost two nuts now - the problem is even though size 8 nut is suitable for this, the thread is different, sometimes, you have to force it in with a player. I am gonna get some prop savers - it is safe as the name says !!

What I understand is, if a prop went off in mid air, your bird should have hard kissed the mother Earth - But you don't seem mentioning it ;D

Oh it did flip and fall. But it was hardly 3 feet above the ground and nothing happened. Satya Sir has very generously offered to send me a prop adapter set and I will use that. How do you use prop savers with a quad? Aren't they meant for planes?

I have done some more reading and I have realised that we are bound to keep losing nuts. Since the nut is screwed on clockwise, and 2 of the motors are spinning counter clockwise, the opposing directions will cause the nut to loosen. That is why there are some counter clockwise threaded prop adapters for sale. The only solutions seem to be to use Loctite, Nyloc nuts, or a CCW threaded shaft. As a side note, does anybody know where we can get Nyloc nuts in India?

well I chose prop savers, because in my place all those alternatives are hard to get.

Prop savers are best for quads - even professional video graphers are using it - in small crashes propeller and motor shaft will be saved if using prop savers.

From what I read prop savers are a better option only for smaller quads. They have a higher risk of failure and increase vibrations, causing the 'jello' effect in aerial videos. Anyway, I don't think I can use prop savers since my adapter is 5mm (no prop saver is that wide) and my motor shaft is too short to put a prop saver on. I am just going to buy some Nyloc nuts.

Ha ha, I was suggesting propsaver with out knowing which is your motor . :banghead: .

I got my power distribution harness today. The quad is looking much neater. I just need to get a nut which fits my motor  :P ! A spare prop adapter set is on the way from Satya Sir  :thanks:  and I can't wait to get my quad off the ground!

I just noticed that one of my motors seems slightly harder to turn than the others. There is a more distinctive 'click' feeling as I turn it each step. I suspected a short but the resistance between any two of the three motor wires is the same as the other motors. I am worried that this may be a problem. Should I try disassembling my motor? What could the problem be? Is this a threat to my quadcopter? How should I go about the disassembly. BTW I have SunnySky x2212 980 kv motors.
Appreciate your help.

That is not a problem at all - it will be smooth after two three runs.

Here is one of my first decent flights. Right at the end there is a momentary power failure in one of my motors. http://www.youtube.com/watch?v=JhAQYoSSodA#ws (http://www.youtube.com/watch?v=JhAQYoSSodA#ws)

That's Far better than my First flight :thumbsup:

And I like that Lane very much, Which is this place ?

Thanks but that was not my first flight ;D. Just my first recorded flight (that was reasonably good). The place is the lawn of my layout clubhouse.

That's a very good place, I should say.

A few updates on my quad.  I have installed a shock dampening setup on my landing skids: 4 smiley balls that have undergone a lobotomy  :giggle:  They are doing a really good job as landing gear. My Wild Scorpion 3500 mAh 30C battery is an awesome battery.  :thumbsup: to RCMumbai It gives me around 10 minutes of flight time and barely gets warm. My WolfPack 2200 mAh 25C is not doing so well though. It gets pretty hot after less than 5 minutes of flight and the voltage starts dropping so much that the quad does not even lift at full throttle. I understand that I am running the motor close to it's max draw ( 23C is the load according to eCalc) so I can't really complain. Also, I have not tried equivalent batteries of other brands. The battery is good for quick testing and has a really good mAh/ :Rs: ratio. I have replaced the stock SunnySky prop nuts that keep getting loose with M5 Nylon Locknuts from Indian.Hobby.Shop. They are really good and I need to tighten them very slightly only after several flights. I plan to get a FlySky 9x soon and upgrade to APM in my summer vacation. I am considering adding LED lighting soon as well. I will put up some videos once I find someone to take them.

Good Luck and best wishes, well, beginners do face many types of soldering issues, there are some very tiny ones like SMD components,  to some little larger ones, the joint you wanted to make, can be solved by 10W iron, 25W can also solve ur issue, while soldering don't lift the iron or sake at that tip, it will melt because the suurface needs heat too, when both surface and components reaches melting point you get a perfect solder, don't give pulse heat, when you feel it is heated take the solder wire as it also contains flux, for a smooth joint, I am into TV , Motherboards services,  I like to buy any burnt ESC or any Electronics junk , I am also interrested buying all types bad batteries , from anyone of you RC guys,  can refer them to me 9820881300 Stanley Benjamin Dsouza,  Santacruz East, Mumbai

Hi, As you said that, you damage your 3S, well give me some details how did you damage,  next send me the pic via whatsapp on 9820881300,  and 8451077566, I will guide you, how to recover

Hi, Add 1500 Mfd 16Volt capacitor, 2000/16v  to the supply line, see the polarity before connect ing, else it will get hot and burst, just push the lead into the connector, be careful,  that it does not sort, while putting, Hope you will get power, because some batt are bad and unable to give power, use the best configuration chargers, because here you destroy good batteries,  secondly it does not give exact ratings,  do not use Transformer chargers, use SMPS onces, and many smps chargers are bad, in configuration... I give you a fair  example, I have my Tablet, with it Comes a charger,  but I don't use it, because after full charge it drains out quickly,  but when I use lower amp charger of my other mobile it, gives me good long time usage,