Jump to content

Recommended Posts

Hi,

Have just putted a new Airwave 450mW TX,

and new Dynam RX in plane.

When flying over some power lines 300 meter away, radio contact is lost..

See what happen, i could do nothing than following the video downlink..

Well videolink worked just fine :-)

Sorry, for very bad video quality.

(There is something wrong with cam probaly, horizal lines + color is bad + red glow because of misplaced black "tape" on CMOS cam)

How much range to expect with a Dynam PPM 6CH RX?

Cheers,

LoopForEver

Share this post


Link to post
Share on other sites

Loop brings up something I have wondered about.

Does anyone here have or know where to find the output power specs for different manufacturers R/C Xmitters? I'm thinking like Futaba, JR, etc.

I know I have seen one and I can't remember which it was but it was listed at 600mw output power.

Thanks,

Curt

Share this post


Link to post
Share on other sites

It varies between countries and frequency bands. But what counts the most is not the TX, it's the RX in the plane.

Did you do a range check comparison with video TX both off and powered? Such high TX powers can easily cause drastic range reductions with bad placement/poor quality receivers.

The image quality seems like a mix of bad quality CMOS for the colors (are there good ones anyway?), vibration for the thin fast moving lines, and bluetooth/WLAN for the wider horizontal lines appearing sometimes when the signal is low.

Share this post


Link to post
Share on other sites

>It varies between countries and frequency bands.

Mine is 35MHz Channel 64.

>But what counts the most is not the TX, it's the RX in the plane.

>Did you do a range check comparison with video TX both off and powered? Such >high TX powers can easily cause drastic range reductions with bad >placement/poor quality receivers.

Know that, i will try to do some more tests.

My question where more how long do you guys go with a 500mW TX next to receiver?, and what RX/TX radio systems are you using.

I just changed my old Multiplex IPD RX out(455kHZ filter died on crash, anybody have one?), with a new Dynam R6P.

I noted the antenna is shorter than my old Multiplex,

maybe its a 1/8?

Thomas have done some great findings with Receivers,

including the Dynam R6P 6CH(8CH with soldering skills ;)

Not the best, but cheap.

Dynam R6P test

Link to test off RX systems

I will do some range checking.

>The image quality seems like a mix

>of bad quality CMOS for the colors

The red in bottom is due to light coming in on "wrong" areas on the chip,

(Will try to put some black tape on, the black tape is misplaced a little)

The CMOS is pretty good with good color when connected directly to TV,

but very slow to change light conditions.

Have now changed it out with a Sharp 1/4 CCD, powered from 9.6V RX battery..

Much better quality, still a little lines that changes with motor RPM.

But WAY to much "light" in picture, its seems overexposed.

(Camera+TX is connected directly, do i need to put a resistor to ground?,

or cap(what size?)

>and bluetooth/WLAN for the wider horizontal lines appearing sometimes when the >signal is low.

Due! Use a laptop to see live video, with WLAN..

Hehe.. :lol:

(Also my neighbord do have a wireless internet connection TX/RX to 8KM away,

maybe that on the 2.4GHz band also..)

Cheers,

LoopForEver

Share this post


Link to post
Share on other sites
My question where more how long do you guys go with a 500mW TX next to receiver?, and what RX/TX radio systems are you using.

Gave up on the idea after having 2 unexplained crashes on different planes in a row, only common point being the 500mW TX, which was already as far away as possible. During some ground tests I've come to see that even far away, depending of component orientation the receiver could be totally fooled.

Futaba 40MHz TX and 149DP dual conversion PCM RX.

In my common planes I use alot of different (Hyperion, Futaba, Schulze,...) receivers. My TX is a Futaba 9Z.

Now I always stay with the allowed 10mW. In any case not more than 200mW.

But WAY to much "light" in picture, its seems overexposed.

(Camera+TX is connected directly, do i need to put a resistor to ground?,

or cap(what size?)

Airwave modules need a coupling cap in series with the video. I think the the value is specified in tha datasheet (check the AWM module thread in the for sale section), or else 330uF will do it.

Due! Use a laptop to see live video, with WLAN..

Hehe..  :lol:

Hehe... You just learned to deactivate it before taking off ;)

Share this post


Link to post
Share on other sites
Airwave modules need a coupling cap in series with the video. I think the the value is specified in tha datasheet (check the AWM module thread in the for sale section), or else 330uF will do it.

Kilrah, Do I need a decoupling cap (between Camera and AWM) on the TX side as well? I just know about the decoupling cap on the RX side...

-AT-Loop: I like your video! :unsure: It happened to me a couple of times already. So the recorded video was the most effective help to find it again, even in total darkness after a night flight (that was a horror trip :blink: )

I'm glad your plane is fine. Once I lost control exactly the same way flying close to power lines. They seem to radiate so much "noise" even in RF that the AGC of the RX receiver seems to turn down sensitivity and doesn't "hear" the Remote control's calling anymore. It might also behave like a shield. So now I make sure to either stay from them or to fly high enough with lots of margin so they can't block my control's signals by being in the line of sight.

Edited by Hartwig

Share this post


Link to post
Share on other sites

Also have a 10mW TX, how long is the range typical with that?,

do you get alot of dropouts?

(Will try it soon)

>Airwave modules need a coupling cap in series with the video

Also for TX?

Do have a 470uF cap on RX side in serie off video signal, + side to RX.

>Hartwig

>So the recorded video was the most effective help to find it again

First i looked at the wrong spot, did replay video again with laptop,

and found it quickly :-)

Do you have any videos with the "bad landings"? ;)

>AGC of the RX receiver seems to turn down sensitivity

> and doesn't "hear" the Remote control's calling anymore

Yes, that exactly what happened - just lost control quickly, may be the AGC.

Share this post


Link to post
Share on other sites

Mmh, it's true the datasheet doesn't use one on the TX side. I have put one on mine, but might try without too then. There's the 470uF cap on the bypass pin in the datasheet, that I havent noticed and thus not installed, it worked perfectly without though.

With 10mW it depends a lot on your setup that is more critical than with a bunch of power, especially the RX. A bad quality 500mW set is no problem, you'll still have far more than enough range if the TX ends half the secified power and the RX isn't very sensitive, but with low power you of course don't have that margin.

With a 8dBi RX antenna I regularly fly up to 1-1.3km, then I'm limited by the R/C range and come back :unsure:

Share this post


Link to post
Share on other sites

My very first 10mW system of about 2002 cost me an arm and a leg and had a range of only 200ft out of the box !

Terry

Share this post


Link to post
Share on other sites

Well I went for a flight tonight and not too far from launching, I had lost radio control of my plane ( should of grounded her then). Strange... very strange, but regained control shortly after. I was testing out my new 14db patch antenna and it worked quite well as I predicted. This time I noticed video ripping, something I heard about but never personally experienced. Anyhow I flew quote, I think 2.5 to 3 km up and then I lost total control! I believe the wing folded and if that happened, then it would of ripped my wiring out and that could explain why I might of lost radio and video signal. Anyhow thank god that the property I flew in was very large, actually this person owns a small mountain on her farm. So guess where my plane crashed? Yup of course on one of the three rock face somewhere. So if the weather man is wrong (suppose to rain this weekend :( ) I will have to do a little up hill climbing and some rock climbing to retrieve the wreckage. ohh fun.

I hope the forest will shelter the planes' electronics/motors from the predicted rain. I'm posting a video as I am typing so by tomorrow I will provide a Megaupload link. (hope, for I seem to be having troubles uploading with them too :( ) I tell you when problems comes, it doesn't always trickle but sometimes pour all at once :huh:

JMS

Share this post


Link to post
Share on other sites
I flew quote, I think 2.5 to 3 km up and then I lost total control!

Sorry for the loss... :(

That is already very far with stock R/C.

The best loss of control I've had was a VERY lucky one. It was with a glow engine trainer by the sea. Flew maybe 15mins, went far up and decided to stop the engine to glide down smoothly without the vibrations. About 15secs later, no more control. The plane glided down smoothly as desired, but on its own... flying large circles, half of each being over the sea, the other half over land. Very fortunately it landed on the land part, with about nothing more than a broken prop. The culprit was the RX battery deciding to disconnect itself... and the most annoying part, I had noticed the plug between the battery and switch harness was a bit loose, and thus had put some tape on there. The tape didn't stick to the plastic correctly...

Very fortunately again, that didn't happen 15secs earlier. The ending wouldn't have been the same with the engine running and a tank large enough for it to fly 10km out over the see if it had fancied it...

Edited by Kilrah

Share this post


Link to post
Share on other sites

Ouch! I feel your pain JMS - my nightmare as well. We don't have a lot of field to fly here and there are trees everywhere so I think we all share the same nightmare. The worst thing would be to come down on traffic or someone. Fortunately that didn't happen in your case. Hope you find your plane back in one piece.

On one of my recent FPV flights, after I landed, I noticed the rudder had popped out at the hinges! Needless to say I was thankful it didn't happen in mid-air.

Daniel

Edited by Daniel Wee

Share this post


Link to post
Share on other sites

normal RC systems are designed to perform with a good margin for VISUAL flying only !

that means up to 300-400meters, normal people can not see and control a plane safely over those distances, but you can with FPV video links.

the margin I talk about let you in some cases fly 1-2km away, even futher on some installations, specially 72Mhz gear is know to have longer range over 35 and 40Mhz.

so if you want to fly futher away, use a special constructed RC system,

that is designed to give you a relayable link at the range you need,

if you use stock RC gear at 1-2km range

you will fail, crash, or have to pay huge compensations if really bad things happens.

remember the terms stated in our insurence policy !

they MUST be followed to get money from them in case you need it.

please read this thread about FPV safety:

http://www.rcgroups.com/forums/showthread.php?t=616667

Edited by ThomasScherrer

Share this post


Link to post
Share on other sites

Thanks guys for the support.... better than getting a hug :rolleyes: Hee hee... anyways things happen so move on I do! Here is the vid for you guys to see... right to the end ( loosing all signal up in the air. ) http://www.megaupload.com/?d=LZ67DPCQ

JMS

Edited by JMS

Share this post


Link to post
Share on other sites

>JMS

Have also tryed a wing flap some years ago, when flying really high.

When you fly HIGH you get up i "lighter" air,

and can then fly REALLY really fast, that where bad wings will brake in dive..

Hope you find your plane very soon,

rain is not that bad, if you clean everything after.

Hey, do you have another video plane you can use to find/recover old plane ;-)

(Downloading video now)

>Thomas

I where only flying about 300meters away, when radio control got lost,

and have good visual of my plane.(Its 2meter in wingspan)

(Okay it where a cheap new Dynam 6P receiver, with a 450mW next to i, that probaly why)

>if you use stock RC gear at 1-2km range

>remember the terms stated in our insurence policy !

Ofcause, if your are very very unluckly to hit a car/person your screwed!

But sometimes there is a risk when you do things that can go wrong,

like everytime you drive a car, flying, or controlling you airplane.. - but safety first.

Have a nice day all!

Will upload a video soon with new cam+new power system.

Cheers,

LoopForEver

Share this post


Link to post
Share on other sites

That video nearly made me sick... :blink:

Was the über-shaky flight due to glitches?

Share this post


Link to post
Share on other sites

ok loop now I have seen the video,

yes your cam is really bad looks like the really cheap cmos types,

get a read CCD cam like kx131 or kx151

http://rangevideo.com/index.php?main_page=...85e32cd07556ec0

chose the one that you can afford.

the stribes and noise you have can be several things:

mecanical vibrations on cam or tx module, check and improve,

voltage noise from regulator, or bad wiring and bad decoubling filtering,

check at improve,

also try to make more distance from TX to any other things,

specially to your RX and your cam and other wires.

About flying FPV or normal RC planes:

when you discover flips on RC, you MUST return home,

get closer to avoid total loss, ok you found out the hard way,

your crash could have been avoided, it was close to roads, and houses !

you could have ruined your self and caused serious harm to cars or persons.

imagine the senario on a road people drive 80kmh and suddently an RC plane hits a car on the front window, the driver will maybe change lane to avoid the plane, hitting another car in the other lane, you continue the story..

Share this post


Link to post
Share on other sites

Wow, you where really high up! (Any clue?)

Seems like plane wings break up, with the high speed, like you say.

>Thomas

Yes, really bad CMOS camera, have tryed with a Sharp CCD, much better result, but overexposed light, and still some lines.

(Seems like there is a loose connection IN CMOS camera, it goes from good color to near B/W(like video) when i hit it hard)

>when you discover flips on RC, you MUST return home,

Sure, but what you can not see in video, is that i lost orientation when servo flip occurs, and try to get it home, but too late - control just lost after that! (AGC noise..hmm)

Even did pull my radio TX antenna in a little before flight, so i could take it out, if servo flip did occur, but did not help much.

I do NOT fly over the highway intentionel,

it first when control is lost it goes there.

(Yes im near the houses in the start)

>caused serious harm

Yes i know, but somehow when you high up, you are near many things. (like your field in sjælland, near a road and railroad)

But i totally agree with you, bad things can happen if you very unlucky,

and we must do everything to not come in that situation.

Now back to a more good subject :-)

What brand is KX131(Sensor chip, DSP chip type etc?)

Will go back to try to find the issue with the lines, and seperate all systems.

Cheers,

LoopForEver

Share this post


Link to post
Share on other sites
ok loop now I have seen the video,

yes your cam is really bad looks like the really cheap cmos types,

get a read CCD cam like kx131 or kx151

http://rangevideo.com/index.php?main_page=...85e32cd07556ec0

chose the one that you can afford.

the stribes and noise you have can be several things:

mecanical vibrations on cam or tx module, check and improve,

voltage noise from regulator, or bad wiring and bad decoubling filtering,

check at improve,

also try to make more distance from TX to any other things,

specially to your RX and your cam and other wires.

About flying FPV or normal RC planes:

when you discover flips on RC, you MUST return home,

get closer to avoid total loss, ok you found out the hard way,

your crash could have been avoided, it was close to roads, and houses !

you could have ruined your self and caused serious harm to cars or persons.

imagine the senario on a road people drive 80kmh and suddently an RC plane hits a car on the front window, the driver will maybe change lane to avoid the plane, hitting another car in the other lane, you continue the story..

Hey Thomas!

Actually that road is a long driveway, the cars were ours and the house.... well the owner was with me during the flight.

The shaky flight was due to shaky nerves? :lol: Should had a shot of vodka before flight :P

Yes this was to see what this plane could do and believe me guys, this property is huge! So I made sure that nobody would get hurt except my pride! ;) Funny thing when I saw her helicopter down to earth, she virtually floated down like a leaf! Hey I could of boiled some water, made some tea, steeped it a bit and continued watching her helicopter downward. Soooo slow! :o So I assume there isn't going to be too much damage when I find her; oh I decided to go today after work! Could use the exercise anyways.

:D

Share this post


Link to post
Share on other sites

Ok I got my fill of exercise ( for the entire year! I deserved that!) at the "mountain" and too much leaves were growing on the trees now because it's spring, so I assume she's hampering on some tree top. So the TS FPV plane is a write off.. oh gee. I just don't know what to replace it with now, all I know is I want to go lighter, slimmer, coast slower and fly longer like a glider! ;)

You know I flew up here on a Cessna and the scenery is awesome! If I had succeeded, I should of been able to ( while gliding back down ) see the Juan de Fuca Straight, Gulf Islands, city of Vancouver (CND) and the snow capped Mount Baker/Mount Rainier (USA). Ohh I can hear Christopher Cross singing his hit song "Sailing" now. :lol:

Edited by JMS

Share this post


Link to post
Share on other sites
ll I know is I want to go lighter, slimmer, coast slower and fly longer like a glider! ;)

Easyglider!

As a side note, it flies very well with one aileron only... says yesterday's flight :P

Share this post


Link to post
Share on other sites

VERY COOL KILRAH! I think you know how I tick or ...think! :lol:

BTW folks.... in case some of YOU are thinking my latest flight was nutty, well the truth, the facts, the laughs, the horrific graphical images... ahhhhhhh ... scary stuff... Yes folks the comedy SOAP OPERA continues here on this link. So if you dare.... click here! http://www.rcgroups.com/forums/showthread....t=696837&page=2 :lol::blink:

Share this post


Link to post
Share on other sites

>JMS

Sorry you could not find it, but you got some rock climping ;-)

Small=Multiplex MicroJet its very small and go very fast,

"Speed FPV" hehe, just kidding.

BR

LoopForEver

Share this post


Link to post
Share on other sites
>JMS

Sorry you could not find it, but you got some rock climping ;-)

Small=Multiplex MicroJet its very small and go very fast,

"Speed FPV" hehe, just kidding.

BR

LoopForEver

Oh yeahhhh sure.... what was that???? Darn moved too fast by that :o

Yeah rock climbing..... my thighs and calves are pretty tense now :lol::lol::lol:

Share this post


Link to post
Share on other sites

I am just getting into the FPV flying (need money first) but I am looking at adding a PicoPilot to my list of must haves when I start putting my plane together. That way if signal is lost it will fly autonomously back to the start location. I could also use the PicoPilot to fly to waypoints that I program so I can look around without worrying about controls. In theory, if I do lose the plane I can use the GPS last known Lat/Log and a handheld GPS to find the plane. Thought this might help other people that might fly out of sight FPV.

Here is the PicoPilot website.

PicoPilot

Share this post


Link to post
Share on other sites

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now

×