Thoughts on HKPilot V2.5 flight controller?

RoyBro

Senior Member
Mentor
I'd love to see this one as well. Granted it is supposed to be a cheap China made version of the Audrino board. But that's the part I like... cheap. If it works as well as the $250 model, I'm in.
 

zev

lumpy member
ooh, that does look cool. though I feel kind of bad about buying the chinese ripoff of an american product… but its so cheap :p
 

epic.engineering

Senior Member
I plan on running one on the v-tail I'm building.. this is an exact copy of the audrino board. Even the sensor that are used I believe are the same. The audrino is open source and that's why they are able to reproduce and sell it. So components and programming is interchangeable.
 

Cyberdactyl

Misfit Multirotor Monkey
Yea, I do love the KK2, but with all the heavy woods around my house, I really should make the change over to having a RTH capability. I initially wanted to do FPV over my woods, but now that I've lost a quad to them, I'm paranoid about losing my video feed, because I lose line of sight past a couple hundred feet.
 

epic.engineering

Senior Member
Yea, I do love the KK2, but with all the heavy woods around my house, I really should make the change over to having a RTH capability. I initially wanted to do FPV over my woods, but now that I've lost a quad to them, I'm paranoid about losing my video feed, because I lose line of sight past a couple hundred feet.

I read that 2.4gtz doesn't penetrate well neither does 5.8 so I'm thinking about a 900mtz on the video and trying to extend the range on the dx6i.. keep me posted on your setup as there are a lot of trees around many areas I fly also.
 

xuzme720

Dedicated foam bender
Mentor
That's true, the lower frequencies do penetrate better, but most of them require ham licenses to operate. In the states, it's pretty easy to get a license though, so that really isn't a big hurdle.
 

epic.engineering

Senior Member
Shhhh! lol
No, 5.8 and most 2.4 are legal to operate. That's why Fatsharks are fine!

I'm pretty sure in the U.S. 1.2 and 900 are legal also. Both are reasonably easy to buy in the United States. As I understand it, the lower the frequency the larger the antenna is, however the lower the frequency the better the penetration through objects like trees.
 

earthsciteach

Moderator
Moderator
This has been debated quite a bit on this forum. I will defer to those more knowledgeable than me, but from what I've seen, there is no exception based upon frequency.
 

Craftydan

Hostage Taker of Quads
Staff member
Moderator
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In the US, It's legal if you have a license. That's covered by part-97 of FCC regs (highly recommended reading for insomniacs).

Transmitting RF *might* be legal if you don't. It all revolves around it being a part-15 compliant device (like your cordless phone, wifi, or wireless security system).

For part 15 compliance, the OEM must have their device measured, certified, and registered with the FCC prior to sale -- many of the "new gadget in the works" leaks are from public records of this testing. Along with this are certain design considerations, like making the antenna non-removable/non-modifiable/non-standard. This is so you can't go in and "boost" the power by swapping that whip antenna with a "better" one you bought at radioshack (as if they'd have something better ;) ). There are also signal type considerations -- digital like our control radios is fairly loose, power wise, where analog like an FPV video signal is typically allowed only a 10th of the power.

Again for you to use it legally without the license, the OEM will have needed to go through this design and testing process. Unfortunately, if you want an FPV system with any reasonable range with analog video, the system will have to have higher power than allowed by part-15 and therefore for it to be any good it will completely fail the certification process.

Think of your control TX -- it's got good range, but it can tolerate a high error rate before it drops control. Now cut the power by a factor of 10, and demand a good signal to be useable. Control Line FPV anyone?

There are some digital video systems that are trying to take advantage for the higher radiated power. Promising, but many of them are still very short range because the bandwidth is much larger than the control signal and the error rate MUST be much lower.
 

xuzme720

Dedicated foam bender
Mentor
I thought the 5.8 band was still legal without a license in the states...? Or is that some more of the internet hooraw affecting the old brainbox?
 

Cyberdactyl

Misfit Multirotor Monkey
I need, or want, video tx range of around 1000 feet to explore my woods. My Fat Shark 250mW tx is easily good for that in clear LOS, but through heavy tree canopy starts breaking up bad around 150-200 feet. I have yet to test several hundred feet into the woods with bare 'winter' trees where line of sight is ~possible.
 

Craftydan

Hostage Taker of Quads
Staff member
Moderator
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License free 5.8 devices are still "blessed" via the part-15 cert. There's nothing unregulated about any RF band - just exceptions for who needs the the blessing to opperate. 5.8.and 2.4 have been viewed as unregulated, since the processes of getting a license free device have become liveable for OEMs.

That being said, there are exceptions in part-15 provided for experimental and hobbyist devices - which is why you'll find rf gear for arduino projects in electronics hobby stores. As nice as it is for that freedom, they still have to comply with the power and bandwidth limits. They also don't apply to us, unless you're soldering components onto homemade pcbs.
 
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xuzme720

Dedicated foam bender
Mentor
I need, or want, video tx range of around 1000 feet to explore my woods. My Fat Shark 250mW tx is easily good for that in clear LOS, but through heavy tree canopy starts breaking up bad around 150-200 feet. I have yet to test several hundred feet into the woods with bare 'winter' trees where line of sight is ~possible.
It's a toss-up and really depends on just how thick the woods are. From the pic you posted on the lost quad, they look pretty thick and you would probably benefit from a lower frequency. But Fred (Flyingmonkey) has a couple of videos showing his FPV trips through woods. They don't look as thick as yours but the canopy can be deceiving as you know since it's much thicker up there than at ground level.

Here is one of Fred's videos he flew on 5.8G Fatsharks. The video is not taken from the FPV at the goggles but from his GoPro. He said he had a little drop-out, but it was always flyable and never lost video signal for more than a fraction of a second at a time.