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Posted by ej189 | Jan 09, 2015 @ 01:57 AM | 5,713 Views

Always feel happy flying with V120D02S form the day I got my first 02S since 2012 January. Not the best heli but good enough to do mild 3D without any modification. Later I found it’s outstanding in durability and easy maintenance that lead me to try many dangerous maneuvers without worry and fear. That’s pretty helpful that I can pick it up and try again with no serious check or test or days of repairing, that did save me huge time and money.

Though there are some minor issues but it’s also easy to make up. Reducing friction and fine tuning cost you nothing but could fly it in efficiency and reasonable, a slipper clutch mod with metal gear A will stand for more crashes, a faster motor (or higher motor gear to 11T) will drive more power out, a lighter blade will fly agilely, a lighter weight gets punching fast, a powerful battery could drive the bird much harder, maybe a new gyro to fly more handy.

The theories are all there, rest is how further you want to dig in.

Actually I am too success treating V120D02S to fly any other heli that I had leaved my two EP200 and HK250 for more than 2 years.
Had heard folks saying good and bad of it, mostly agree but some don’t. V120 just like my child that she has some specific characters, just treat her nice and she will pay you back.

The most talked about V120 is that 1S battery is not enough for 3D unless doing serious and costly mods. I can’t agree with this since years ago.

Let the video talks.
...Continue Reading
Posted by ej189 | Oct 24, 2014 @ 02:28 AM | 6,327 Views

The first mind of DIY canopy is to color the little bird for visibility in flight, start form the popular paper canopies of mCPX, but the shape doesn’t fit V120 at all, thus I decide to build it by myself form scratch.
Soon I found almost every paper canopies are marked with *.pdo file extension, then I got Pepakura to read the files. As soon as I realized that Pepakura can’t create 3D model, then I got another software called “Super”. Actually there is a Chinese word in the header of its name but you may not see it correctly so I leave the link for you.
Super had been sold and renamed as Clip Studio Modeler in 2011.

I stared to build 3D model with Super 5.5 form scratch, actually you may using many other 3D modelers for Pepakura to transform into plane paper, but the “Super” may fit best and also easy for 3D modeler.
First I scratch the canopy projection image of V120d02s.

Then calibrate the shape and dimention.
...Continue Reading
Posted by ej189 | Sep 03, 2014 @ 10:07 PM | 7,651 Views

Since Deviation project giving us the ability to get away from Walkera’s receivers, it is a great chance to leave Walkera’s defective gyros and seeing others out of the well.
A great product is called GY280RX that came with a cloned Vbar gyro core and DSM2 receiver, also equipped with micro connectors that totally fitting V120D02S. The only thing needs to be careful is 1S battery system may drain the voltage down too low and waving gyro’s detecting level. Fortunately the seller also provides a 2A booster for you to plug and play.

New gyro provides a great improvement in tail lock and pirouette compensation, also makes V120D02S behave more natural and stable than ever. Plus the durability of V120D02S and slipper clutch mod, the combination makes it being the top grade micro heli in the world.

V120D02G Smooth Flight (6 min 48 sec)

With the encouraging of GY280RX, I soon convert two of my birds and flying happily.

Though GY280RX is good enough but seems not good in price compare to such cheap clone bars. After go through the setting and usage of GY280RX, I figure out that it is nothing but a compact clone bar. The cheapest clone bar here costs less than US$20, why not mod it by myself to save more than 50% off GY280RX?
Moding is easily be done than thought, just removes shell, heavy USB and standard connectors, then soldering micro connectors and satellite receiver. The difficulty is planning, once you figure it out, it is nothing but a...Continue Reading
Posted by ej189 | Aug 06, 2014 @ 04:47 AM | 6,868 Views

Seems we all have known that Deviation firmware had make Walkera DEVO RC transmitter become the most cost effective Tx in the world. The most valuable thing is supporting multiple protocols that we will no longer be kidnapped by one brand with expensive controller. Except that, how good the controller is? Can it compete with those expensive Txs? Had made a test in 2012.

First is the resolution of Tx.
I setup the trim step to 1 (minimal) then found WK2801 can provide 800 steps in one axis and DEVO10 provides 1600 steps. And even a minimal move can be observed on servos which be connected to the receiver.

Second is the speed of data transition.
There is a authoritative report about Tx latency test that made to measure control latency since the day eCCPM had played a important role but causing huge latency.
TX/RX Latency Test Results
I also had done the test for 2801 and DEVO:

DEVO10+RX1002(11ms): 16ms
DEVO10+RX1002(22ms): 19ms
DEVO10+RX701 : 28ms
DEVO10+RX2622V-D: 15.5ms

WK2801PRO+RX2801PRO: 29ms
WK2801PRO+RX2622V : 20ms
WK2801PRO+RX-2702V: 17.5ms
WK2801PRO+RX-2612V: 20ms
WK2801PRO+RX2610V : 25ms
WK2801PRO+RX2609: 29ms

...Continue Reading
Posted by ej189 | Jul 22, 2014 @ 04:09 AM | 6,656 Views
From the experience through 4G3, 4G6, 4G6S, V120D02, V120D02S, I always leave Walkera manuals alone and doing test by myself. Each gyro has its unique characteristics, by now I can only remember RX2622V form V120D02S. Common sense will be ignore, let me talk about the defects.

1. Never tuning swash limit in ADJ mode. ADJ switch will control swash limit by channel limit(TRVADJ) on transmitter, but after back to WK mode the swash will go full extension that controlled by the gyro not the Tx.

2. ELEV/AILE EXT. will not limit swash extensions but only servo speed, that id totally the same as dual rate control on Tx do. And this two settings (on Tx and Rx) will combine together to determine swash moving speed.

3. RUDD EXT. does limit tail pitch throw, but may different from rate mode to heading hold mode. In HH mode (tail gyro sense more than 50%) the servo throw always using 100% of rudd scale, but it will reduce to rudd scale value in rate mode (tail gyro sense less than 50%) if rudd scale less than 100%. That means you should always tuning tail limit on HH mode, and rate mode for rudd center only.

Above is the tuning defects that every one should know of on RX2622V. Beside that, there are some defect that we cannot avoid.

First, the swash curves are not linear from end to end.

RX-2622V/D Swashplate Behaves (1 min 25 sec)

Second, there is a low voltage protection circuit on RX2622V that will cut off motor output when loading voltage lower than 3....Continue Reading
Posted by ej189 | Jul 09, 2014 @ 04:01 AM | 9,599 Views

Playing V120D02S is a pleasure for me that it gave me more than I spent on it, but the bird still need some serious tuning on the crucial spots.
Had found many detail things on my photo album recently, though the skills have all been known for a while, but that is how I can play it for such a long time.

First is to eliminate frictions, every tighten junctions and bearings will cause serious friction to drop down performance.

Every gears should be settled in the right place to get proper gap, the torque tube must long enough or it will push bevel gear away and run out of gap.

Bevel gear B must be sended thinner to leave the gap from gear C, if you don't have slipper clutch that you should sand the spacer thinner to leave flange bearing running smooth.

...Continue Reading
Posted by ej189 | Jul 18, 2012 @ 02:57 AM | 10,109 Views

Have painted National Flag of Taiwan (formal named Republic Of China, ROC) on my film canopy with silver base color.They look so shinning and decent that let me flight much closer than ever. The pleasure is to watch her flying gracefully nearby and doing some awesome aerobatics.

V120D02S With National Flag Of Taiwan (Republic Of China) (5 min 19 sec)
...Continue Reading
Posted by ej189 | Jun 30, 2012 @ 10:00 PM | 9,416 Views
A wonderful trip and flying especially with my shining canopy.