September 27, 2014

Broken and fixed single-wire receiver with the CC3D

I messed up today. Big time. I was preparing to wire a Fasst S-BUS receiver to a CC3D. I do this by removing the servo connector and soldering the wires directly to get a more compact build. I'm using the Corona R4FA-SB which can either operate in 4-channel PWM mode or a "special" mode with S-BUS. PPM and RSSI-PWM outputs. I intended to use it in special mode with the S-BUS wired to the CC3D.

However, I manged to break it while removing the servo connector pins. The only important soldering pad, the S-BUS one, was broken away from the receiver. This is catastrophic, it might mean that the receiver is ready for the garbage bin.

Lost soldering pad
I managed to track down a new location to possibly solder then S-BUS signal cable. A small area between two tiny surface mounted resistors (I think). So I tried it out.

I soldered the signal cable and the power cables. Wrapped it in heat shrink and added a small bead of hot glue to avoid any possible stress on the tiny signal cable. But when I hooked it up to the CC3D there was nothing.

But I decided to go to Google and quickly realized that you can use the PPM as input to the CC3D as well. It's connected to a different input port on the CC3D and it comes with less precision and higher latency than S-BUS but it'll have to do for this build. Some cutting and soldering and configuring of the CC3D and it worked! Turns out you need to use output channel 2 which carries positive PPM.

CC3D installation with receiver, hidden below

September 25, 2014

Scrap mini-quad build: power system finished

Yesterday and today I managed to get started with the new mini-quad build. I started by de-soldering the connectors on the CC3D as I will solder all or most cables on this build.

I've also soldered the motors and test-run them to make sure the work and spin in the right direction. Looking "good" so far. There are notable differences between the motors.

Motors soldered to the ESCs

Motors and ESCs attached and soldered to the frame

I've also started the build page for better documentation.

September 23, 2014

Scrap mini-quad build, inventory check

I got my last items for the scrap/cheapest mini FPV quad build the other day and it's time for the inventory check.

Parts for the mini-quad build

I few things are not on the picture, I've left out wires, heat shrink and parts for the FPV filter. Right now I'm only short on propellers. I know I have them somewhere. And the FPV OSD. I know I've seen that around somewhere as well.

September 22, 2014

Chinese CC3D

After a long wait I got a chinese CC3D today. I've been warned about these things but I was just too curious to not try it. I already have two original CC3D and they fly great but are a tad bit too expensive for my next scrap build. So I wanted to give this one a try. I bought the CC3D from banggood and got myself a 3D-printed protective case while I was at it.

First impression is positive. Most reports about the CC3Ds have been that they come without bootloader, which makes them more or less unusable by most people. But this particular one came with the latest firmware, which is positive. Hooking it up to the GCS just worked and everything seems to react as it should. I HAVE NOT flown it yet and there are still a great chance/risk that the sensors are not of top quality!

CC3D with 3D-printed hard case

This device has something that is different from the two I already have. It has the SWD connector soldered on the board. I will hopefully never ever use this connector and it does not really matter except for one thing. It does not fit into the hard case that I ordered with it. But it's not impossible to fix.

September 19, 2014

I learned what New Caledonia is today!

I've been waiting almost a month for one of my orders from banggood and the tracking hasn't been updated for 3 weeks. The last tracking information was flight departure from China.

I mailed banggood about this and they just responded that it might be because of the bad weather. But that I should wait a bit longer. And now it turns out that it might actually be because of some bad weather because the airplane apparently dropped my package over the Atlantic where it has been swimming around for a while.

Today, I got the big surprise. The tracking information has been updated and the package was apparently sent from "New Caledonia". Wow. This is like when HobbyKing sent their packages via Fiji. I had too google New Caledonia. Now I know where it is and why it is taking some time...

September 11, 2014

Ridiculous battery connector

I used to fly my 250 helicopters with the same 1300mah 3S batteries I use for the mini-quads. This simply to avoid having many different battery configurations. Those batteries are actually slightly too large for that application. I also used the EC3 connector on said helicopters. Which is not easy. They are hard to fit under the canopy and hard to disconnect without ruining the little helicopter.

EC3 connector on a CopterX 250

The 250 helicopters usually comes with a JST on them and today I finally gave up and started the move to smaller batteries and smaller connectors. I will use a 1000mAh configuration instead. 850mAh is actually the recommended size but most 850mAh batteries have high C-rating and are as heavy as a 1000mAh 20C. And 20C is 5A more than the 15A ESC can handle.

JST connector

I got two batteries in the mail today and they had said JST connector already. Which is great. So I started by changing connector on the CopterX 250. That was easy.

But then it came down to an "old" Turnigy battery of the same configuration I had laying around. This one was equipped with a XT60 connector and a 14awg wire. This is a battery built to deliver over 60A and I'm gonna pull 10 maybe 12 out of it. Alright, so how do you put a JST connector on a 12awg wire?

I did it by uncovering the cable and cutting away half of the strands inside.

After that I used heat shrink tube in two steps to get down to a size that can pass into the JST connector.

Heatshrink step down metod to reduce the cable size

JST connector crimped onto the cable

And then, when it all comes together, it looks really awesome. Or ridiculous. (sorry for the quality)

JST on 14awg wire!

September 7, 2014

Fixes for the CopterX 450

I got a few spare parts today to fix the CopterX 450 after this summers aluminium failure and following emergency landing. I replaced the broken tail servo mount with a plastic stock Align one. Also, the landing gears broke when I took it down and I had a spare Align ones in the drawer. You can see the new servo mount and the new white landing skids in the picture.

Tail servo mount
Tail servo mount

While I was at it I installed a metal canopy holder. I have always dreamed of these when the ordinary servo rubber pops out or breaks.

Canopy holders
Canopy holders

You have to cut out a larger hole in the canopy and there is no going back. Pay close attention not to damage the threads when screwing them together. I tightened them unmounted first to press the outer o-ring together a little bit. This made it easier to make the threads grip while mounting them on the canopy.

Once in place, the work really well. Attaching and removing the canopy is much easier than before and it is still held firmly in place while mounted.


September 3, 2014

Diatone 17# finished

I've had it sitting all put together without flying it for a couple of weeks now. The lack of spare time during daylight has kept me from adjusting the flight controller. But yesterday I got two spare hours and got it done.

I used the TxPID module on the CC3D this time and it went much smother than the previous one. I think I got a decent setup this time.

I've only setup the attitude mode so far. Hopefully I get a few hours this weekend to fly it FPV, setup the rate mode and possibly adjust the camera.

Check out the build page for all the gory details!

September 2, 2014

Diatone 18# from HobbyKing, but not the latest version

Malaysia post lost two of my packages from HobbyKing about 3 months ago. And that's the time it takes for HobbyKing to process the complaint and everything before you can get your refund.

Anyway. With some dollars on the point account I went shopping for some lipos that I've considering for testing a lighter configuration on my EDF and the 250 helis. While doing this I discovered that HobbyKing has a new mini quad frame that they call the Slick 220. It is a Diatone 18# but version 1. Version 1? Seriously, banggood has been selling version 3 for some time now!

The 18# frames are nice and I liked the build quality of my 17#. But they're a bit heavy. If they could (and they should be able to) shave off some 50g from their frame they'd be even better.