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Posted by seurat | Feb 22, 2016 @ 10:54 AM | 1,352 Views
Yep, I was quite surprised when the present arrived: a SYMA X8W quad-copter that my eldest son sent me for Christmas.
And this is quite an impressive quad, considering the price/performance ratio.
I immediately took it apart to see what's inside:
  • DC motors with a 15W and 3 Amp max. performance current rating (gearbox reduction is included).
  • A BK2425 based flight controller (NRF24L01 compatible) with MOSFET dc motor drives and current limiting function to avoid circuit damage if the propellers are blocked.

Posted by seurat | Jan 01, 2016 @ 04:39 AM | 3,187 Views
Yes, after reading many of the posts in "E-Flite Adagio 280 BNF Basic" I decided to make me a Christmas present.
Thanks to all the guys/gals posting in the fore mentioned forum I started by checking all details of this e-gliders construction:
  • Checked the elevator and ruder servos for binding and horn positioning.
  • Checked the correct operation of the ESC/BEC and motor.
Still need to chekc the wing servos, un-mount the motor and check for any metal shavings left over from manufacturing.
I was surprised to see that Horizon Hobby has connected the ailerons via a Y cable, like the flaps. This will require an extra JST extension to separate the ailerons so crow is possible.
I only have Walkera TXs ( 7e & 10), both running Deviation 4.0.1, and have started to program a new model for this e-glider on the 7e. So far I have the channel assignments right and sticky throttle is working fine. I have decided to go with the stock setup of Y-cabled ailerons and flaps to start with. Later I will implement crow and snap flaps.
Good thing I decided to unmount the motor; I discovered that one of the screw base posts was stripped. I need to find a way to reinforce the screw posts in the motor mount plate.
Posted by seurat | Nov 05, 2014 @ 01:01 AM | 2,648 Views
I have used the arduino high speed capture method laid out by Michael Dreher ( and adapted his source code to the arduino micro for analysis of the PPM signal coming from the DSC port on the Hisky H-4Q transmitter. The clock tick is 62.5 ns. This allows measurement of pulses from 3 us to 65.5 ms.
Attached is a preliminary evaluation of the captured data as a time diagram.
The H-4Q produces a positive PPM signal containing 8 channels per frame. Only the first 5 channels are usable: aileron, elevation, throttle, yaw and the DR switch.
Approximate values for max. and min. are based on the output of the DR-SW channel and are measured from rising edge to rising edge: min. = 1 ms. / max. = 2 ms. / sync = 4.5 ms.
The next step will be to write an arduino sketch to decode this PPM signal and produce a USB HID to interface with HELI-X.
Posted by seurat | Nov 03, 2014 @ 08:45 AM | 2,605 Views
This is going to be fun!
I received an IR controlled 3 channel toy heli for my birthday from my oldest son.
Since it turned out to be so much fun I decided to go for something better.
I purchased a bundled HFP100 V2 from TMART with a H-4Q transmitter.
Wow, this little heli works just like the real ones expect for the missing main rotor pitch which is fixed. It weighs just under 50gr. so crashed won't wreck much havoc in my living room.
After some 5 tries I have managed to hover tail-in and land once the battery gets weak.
I bought a 350mA/h LiPo nad tried to wire it in. While doing so I managed to reverse polarity and fried the receiver
Purchased a replacement receiver from Banggood. Took 20 day to arrive.
The heli flew some 5 time with the new receiver and then the elevation channel quit working. The receiver has a damaged elevation channel This sucks.
I decided to order a new HFP100 V2 and use the old one as spares lot.
So what's next? I have decided to buy myself a Walkera V120D02S bundled with a DEVO 10 transmitter for Christmas
I'm waiting for both now.
In the process of waiting I decided to purchase a PPM2USB adapter from Conrad Electronics to see if I could get the H-4Q transmitter to work with HELI-X.
No luck here . It seems every transmitter manufacturer has a different idea on how to code the PPM signal.
I've bought an Arduino Micro and will analyze the signal coming out the H-4Q trainer port.
The analysis of the PPM signal coming from the...Continue Reading