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Old Dec 04, 2010, 11:56 PM
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GoPro it!! You can fix the RF issues. Separation is key. Try and move the vTX away from the GoPro.

I really want to see an HD skyfun!!
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Old Dec 05, 2010, 12:13 AM
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Sydney, Australia
Joined Jun 2006
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It isn't the VTx. IT wasn't even plugged in. It was simply the Go Pro being on that did it. Not sure how the power issues can be fixed. I'll have to think on it.
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Old Dec 05, 2010, 12:31 AM
Flying FPV from the lab.
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Canada, AB, Lethbridge
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very cool, gree!!! I told you it would be too heavy, but looking at your layout, you're likely lighter than mine... I run 2 batteries all the time due to interference. Are you using the video transmitter off the main motor battery? All you have to do is share a ground with the go pro's video output and your rc reciever, and you can ruin the range. Make sure that video and motor/control circuits are separate. You may need to run another small battery for the video tx?
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Old Dec 05, 2010, 12:36 AM
Flying FPV from the lab.
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Canada, AB, Lethbridge
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heres an example of an overweight skyfun:
Sky-Fun-Damentals (3 min 6 sec)

flies nice and smooth, but you gotta keep that speed UP!! Plus it lands like a sack of bricks.
Config in video: 2600mah 11.1v 35c, 2200kv & 7x6, 1100mah 11.1v video battery, heavy 540tvl cam, 2.4ghz 200mW transmitter.

Now, My skyfun pulls about 43A@7.4v WOT w/8x6prop & 2200kv motor. It has just as much thrust as with the extra cell before, minus a bit of speed.
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Old Dec 05, 2010, 01:43 AM
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Lakewood, Colorado
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Quote:
Originally Posted by Gree View Post
Well I am back from the maiden flight. Here's a run down.

Range test with Thomas LRS
Did the usual range test by taking off the TX antenna and walking away until the plane goes into failsafe. I got 18 (big) paces which is pretty damn good! Then I tried it with the Go PRo switched on - 6 paces! LIterally 1/3 the range with the Go Pro turned on, and not even in live video out mode. There was no video tx running or anything either.

I am in major trouble here. Anyone have any ideas?
Well I got *ridiculed* by the usual suspects when I suggested that the GoPro
totally thrashes the range of 433Mhz UHF Rx's. And of course this is a very small plane, so
lots of "physical separation" isn't really possible, especially if you're using it
as your main flight camera, so it's physically wired into your FPV harness,
with a single battery setup.. etc. I don't know what to tell you, except
"ya, that sucks, doesn't it".

BTW, how'd you balance it? The main problem with the Skyfun is that the CG is
so far back that if you put any significant weight in the cockpit (basically anything
more than a battery) it makes it seriously nose heavy.

I finally got my Mega 16/15/4 2200kv with 7x4 prop installed on my Skyfun
today, and did some visual flying. Without any FPV gear it has unlimited vertical.
But with a 2500mAh battery as far back in the cockpit as it can go, I'm already
at the forward end of the CG range, so after I add FPV gear, I'm going to have to
add lead behind the CG to balance it.

BTW, the best way to strengthen the wings is with carbon ribbons embedded edgewise and CA'd in,
not tape on the surface. Minimal Rf blockage, and very light.

ian
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Old Dec 05, 2010, 02:17 AM
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Hey Aaron, as I mentioned, the video TX was not even plugged in. It was a non-FPV flight with none of the OSD gear on board. Yeah you told me so, but I had to give it a shot!

So the range problem really is only related to the Go Pro itself, as nothing else was plugged in!

Daemon, I balanced it by putting a whopping 80 amp speed control on the back, and by hollowing out the canopy at the back to move the battery even further back. It balanced very well actually, maybe just a tad too nose heavy but it flew very well.


At the moment I am leaning towards making it a light SD camera plane with the whopping motor on it...
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Old Dec 05, 2010, 02:18 AM
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Quote:
Originally Posted by Daemon View Post
Well I got *ridiculed* by the usual suspects when I suggested that the GoPro
totally thrashes the range of 433Mhz UHF Rx's.
Well I can confirm it! Funny thing is though, with the Go Pro on my easy star, the range was not effected. I could get 10 paces away from it on range test with my old SD camera, and with the Go Pro it was the same. I think it is the way I positioned the aerials...
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Old Dec 05, 2010, 03:27 AM
Zephyr 66" Blunt
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New Zealand
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Can you test the range again with the receiver and antenna out on the wingtip and the vtx on the other wingtip, I think that is as far as you can get away from the nose, I have always run my vtx antenna on a vertical fin and I am wondering if maybe the lrs antenna might be better there than upfront by the gopro. Lots of choices but would be a good hd plane if it all works out. Good luck.

Mark
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Old Dec 05, 2010, 04:45 AM
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Quote:
Originally Posted by Gree View Post
Well I can confirm it! Funny thing is though, with the Go Pro on my easy star, the range was not effected. I could get 10 paces away from it on range test with my old SD camera, and with the Go Pro it was the same. I think it is the way I positioned the aerials...
Were you piloting through the GoPro on the EZ*? Are you powering it
from your FPV harness? If so, was it same on EZ*?

ian
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Old Dec 05, 2010, 04:53 AM
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Quote:
Originally Posted by mark hitchman View Post
Can you test the range again with the receiver and antenna out on the wingtip and the vtx on the other wingtip, I think that is as far as you can get away from the nose, I have always run my vtx antenna on a vertical fin and I am wondering if maybe the lrs antenna might be better there than upfront by the gopro. Lots of choices but would be a good hd plane if it all works out. Good luck.

Mark
Problem is, you just really can't afford anything as big as an Rx out on the wingtip
of the SkyFun. It's a very thin wing and highly tapered, so by the time you get
the Rx embedded in the wing, there's not much wing left.

Anyway, the Skyfun does have a bigger/wider/fatter fuse rear of the cockpit
compared to something like the Funjet, so the trick for it would probably be to embed
the UHF Rx in the foam outside the cockpit just inside of one of the tailfins, and
then run the antennas out to the wing tips. Doesn't matter where you put the
video Tx antenna. It won't affect LRS range at all.

ian
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Old Dec 05, 2010, 05:18 AM
Zephyr 66" Blunt
mark hitchman's Avatar
New Zealand
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Quote:
Originally Posted by Daemon View Post
Problem is, you just really can't afford anything as big as an Rx out on the wingtip
of the SkyFun. It's a very thin wing and highly tapered, so by the time you get
the Rx embedded in the wing, there's not much wing left.

Anyway, the Skyfun does have a bigger/wider/fatter fuse rear of the cockpit
compared to something like the Funjet, so the trick for it would probably be to embed
the UHF Rx in the foam outside the cockpit just inside of one of the tailfins, and
then run the antennas out to the wing tips. Doesn't matter where you put the
video Tx antenna. It won't affect LRS range at all.

ian
I think you will find plenty of room at the wingtip for the receiver, I had a 6 channel Futaba one in mine still in it's case and it did not stick out at all.
I just like balance was why I suggested the vtx on the opposite wing.


Mark
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Old Dec 05, 2010, 05:53 AM
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Sydney, Australia
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Quote:
Originally Posted by Daemon View Post
Were you piloting through the GoPro on the EZ*? Are you powering it
from your FPV harness? If so, was it same on EZ*?

ian
Yeah my easy star uses the go pro as the FPV camera, but no it is powered from its own battery. Like I said no interference as far as I can tell with the LRS 8 channel receiver. However the camera is about 60cm away from the aerial of the RX come to think of it!

I'll get back to the Skyfun in a couple of days when I get back from a work trip... Thanks for the input everyone - you've given me much to think about.
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Old Dec 05, 2010, 05:56 AM
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Quote:
Originally Posted by mark hitchman View Post
I think you will find plenty of room at the wingtip for the receiver, I had a 6 channel Futaba one in mine still in it's case and it did not stick out at all.
I just like balance was why I suggested the vtx on the opposite wing.
Unfortunately the Thomas LRS 12 channel receiver doesn't really lend itself to a wingtip placement because of its size and also the fact 2 antennas come off of it (for diversity - hence me using this receiver)...
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Old Dec 05, 2010, 03:52 PM
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Auckland, NZ
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Have you tried filtering the power source by means of a LC filter?
It will surely make a difference.
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Old Dec 05, 2010, 04:16 PM
Flying FPV from the lab.
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Canada, AB, Lethbridge
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Quote:
Originally Posted by bingo17 View Post
Have you tried filtering the power source by means of a LC filter?
It will surely make a difference.
He is saying that the gopro causes the interference even as a stand-alone unit. No wires connected at all - just running off the internal battery of the go pro
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