HobbyKing SS series 18A ESC.

As I bought the ESC’s for my TriCopter I was thinking that no matter what,
it should be able to drive the DT750 good enough, with or without updated firmware.
With this in mind, I bought the HobbyKing SS 18A ESC.

HobbyKing SS 18A








If you look closely the sticker indicating battery and output ports a reversed 😉

This was probably a good idea, they’re cheap, can be programmed with a Turnigy program card,
and when I received the ESC’s, I was that they were fitted with the ATmega48 MCU.
This is nice, as I own a USBasp, so the new firmware for those can easily be programmed to those.
BUT: Some of these boards have their nRESET pin disconnected through the fuse bits.
I haven’t tested it though, as I still need some of the parts, to build the entire copter and then testing the settings
by the programming card.

Instead let’s look at the FETs onboard these things:

P/N FETs of HK SS 18A








The SO-8 chips are soldered on in pairs, not very nice work, but the solderblobs between the pins are okay, as they’re connected to the same spot on the PCB.
The P-FETs are Si4425, -30V -11.4A@Vgs= -10V.
The N-FETs are Si4856,  30V 17A@Vgs= 10V.

One thing I noticed was the one of the boards was fitted with the A1730 P-FETs.
These are -30V -6.5A@Vgs= -10V.
Those FETs will probably do fine, but I really don’t like the idea of just replacing one part with any other.

The FETs are chilled with a layer heat-transporting goo of some sort, it’s black, and sticks a bit to the FETs.
On top of this is a aluminum plate, just pressed on to this:

FET Chiller









The topside, confirming the ATmega48 chip, as well as the programming pins:

HK SS 18A ATmega48









Left side to right:
7805 – 5V voltage regulators, SO-8 on top is another 5V regulator,
a bunch of resistors, some transistors and of course the ATmega48.
The programming pins on the right is like this from the top:
nRESET – Pulled up to Vcc by 4k7 resistor.
VCC – +5V
GND – 0V
SCK – Clock for SPI interface
MISO – Input for SPI data
MOSI – Output for SPI data

I don’t now what my idea with this post was, other than inform you about the product from HobbyKing.

I’m not responsable for any damage to you or your equipment.

Forgot the trainer cable for HK-T6A transmitter?

Yeah, that’s what I did.

Found a guide here, followed it and modified a bit.

Fortunately I have a bunch of CP2102 USB to Serial converters laying around.
I simply soldered wires on the board directly, but soldered the wires on pinheaders to be able to remove
the wires from the trainer port of the HK-T6A transmitter.
Remember when you plug in the CP2102 the drivers may have to install first.

CP2102 - USB to Serial converter










From there just ran to wires about 3 feet, so I’m able to adjust without placing the transmitter in front of the PC monitor,
adding the pinheaders to the wires.

Pinheader CP2102 trainer cable









When removing the header from the trainer port, the header (which consists of two row), moved from each other.
As I were epoxy-fying my DT750 motors, I just pushed in the headers, and put a little expy between them and around the wires.
This will hold it nicely together, making it easier to connect the trainer port.

CP2102 connected to trainer port of HK-T6A transmitter









Tested with this software. It works like a charm!
Now I’m able to reverse the channels.

I’m not responsable for any damage to you or you equipment.

Tricopter build series

Looong time since I’ve been here.

But now let’s try it again.

I’m going to build a Tricopter, based on rcexplorer’s guide.
First of, it needs a frame. As I am the lazy kind, I bought the frame from rcexplorer’s site.

I ordered the frame set and got an e-mail confirming this from him in person.
The frame itself is perfectly cut, putting them on top of each other confirms that now slop was involved in the cutting proces.
The frame was sent through the post office, at friday and got here monday. (I live in Denmark, not far from Sweden).

RCexplorer Tripcopter Frame

I ordered all the electronics from HobbyKing, including a VERY cheap Transmitter/Receiver pair.
A complete list of the components will be written in this blog, once the build is complete.

I bought the pinewood in a shop called Bauhaus, they had it for around 1.5$ for 90 CM.
Two of those, cut in 40 CM length for arms, and drilled a hole in two of them, for the frame mount.

Next is to assemble the frame and pinewood.

That’s all.