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I am pretty sure you all know and worked with these transmitters before. I have the same PCB and 3 different type of Airwave transmitters mounted on it.

I wanted to compare the performance of these with the same receiver setup. The receiver is the Airvawe 623 module and I used 2 receivers, one on the goggles and anotherone on the camcorder. On the receiver is the GP-Patch, copper dipole and steel reflector modified by Thomas Scherrer's dimensions. The camera had a GP-Patch by the same dimensions with a 2mm Aluminium reflector and copper dipole.

The movies were recorded on minidv camcorder. On the first two (10 and 100mW) transmitter are the same setup, except the transmitter. I did not edit the video at all, I did not cut the errors so anyone can compare it.

I did not fly with the goggles since there were other flyiers interested in the system, and I let them watch. Also I tried not to glide out of the imaginary range of the GP-Patch.

On these two videos you can also see a low-tech solution to a high tech problem people are spending hundreds of dollars to do electronically. The virtual horizon and the heading direction problem is solved from less than 5 bucks...

The server may be a little slow it is coming through a Rogers connection. The 500mW video is much longer and slower, included only as a reference - that was my ever first FPV flight.

The videos were recorder in Toronto, Canada, Humber Valley RC Flying field.

Please enjoy:

10mW: 10mW

100mW: 100mW

500mW: 500mW

Also if you feel like it, look throught my previously recorded videos and other projects:

My Video Album

Edited by oxxyfx

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Thanks oxxyfx, I think that shows that 10mW is usable amount of power for anyone who did not already know :)

I would have liked to see the test with OSD of the distance to the receiver though, maybe a job for one of the guys testing their new OSD's !

Terry

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I was planning on doing similar tests with our OSD this weekend, but i've injured my hand to the point that i cant use my left thumb, so that scraps that idea.

I'll try again to get out to our friends farm in 2 weeks after the stitches are out....

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HAHA great solution.

it is possible to get the links for download of the films,

instead of online view ?

Edited by ThomasScherrer

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Sure Thomas. Here there are:

10mW test

100 mW test

500mW First FPV Flight

Sorry Terry, no OSD on this plane, is starting to be too heavy already. It is an Easystar and I had to stick quite a few pieces of lead on the back to balance it properly.

The max distance I flew away was about 300m - 900ft - just as far as I could still see the plane from the ground.

Thanks, Ox.

Edited by oxxyfx

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300m is very close even with 10mW...

Once I receive the OSD I'll have a 10mW and 40mW module so could do a couple of tests - no 400mW though.

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Well the depth of my flying field is limited. I have only about 300m's. The flightline is over the railroads we cannot wonder further than that because there is a highway pretty close after that. I do not have yet a diversity receiver - but I am working on one - so if the GP Patch is oriented toward the railroads the beam of the patch is east and west (0-170 degrees) - as you could see in the 10mW test the first turn was already out of the beam, that's why the video cut out.

Interestingly on my other flights I often ended up a little over 180 degrees west of the GP and while it was cutting out at around 180 degrees, beyond that 200-220 degrees I had still perfect video. And that was kindof behind the GP Patch...

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Last week I did a test with the 10mW from rc-tech. I used the rc-cam patch antenna on the receiver side.

Most of the time I flew about 900 meters far, but unfortunately i was too enthousiast, and i was going further and further... Until my motor-batteries ran out! A bit paniced, I was disoriented and started flying in the wrong direction. Then I had too much noise on the controls of my plane (with an ACT digital dual conversion receiver), however, the image still remained perfect without any noise, and i could see my plane crash into a potato field. After an hour of searching I found my plane about 1250 meters from the starting site.

Thumbs up for thomas: your patch antenna performed a lot better than the rc-tech patch that came with the camera setup (i think it had a wrong polarisation).

The rc-tech transmitter and receiver are brilliant! With the stock antennas they go about 500 meters with some occasional noise, but with a good patch (and a good person pointing it ;-) ) I could go to the limits of my rc-transmitter without any signs of noise.

Does the receiver have some special sensitivity compared to other receivers?

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>Does the receiver have some special sensitivity compared to other receivers?

YES ! since they are designed to work with 10mW legal transmitters,

extra effort in the sensitivity has been made !

other systems are designed for 100 or 500mW so they dont have the same hi demand for sensitivity, to perform nice on long range.

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Until my motor-batteries ran out!

I nearly ran into the same problem on my longest range flight. I was pretty much used to flying at ~1km distance and pretty high, that is always with more than enough energy to come back even with a dead battery, so I didn't actually think about the time to fly back from 1.8km out. I fortunately suddenly thought about it after a few minutes, and it took me 2 good minutes to come back. My battery died just after that. I WILL remember now.

I've rarely used a standard whip on the RX, nearly always a patch. After yesterday's test with a diversity setup using both it seems I should trust it much more though.

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Until my motor-batteries ran out!

Me too !

I was only at about 1k and had 10 min battery in reserve when I turned for home but I had not noticed the wind had changed. It took me the whole very tense 10 min to get back to the field, I just got back into good visual from the ground when the motor cut. No time to prepare for landing, just strait in and hope.

All ok in the end though :P

I keep a closes eye on the wind now ;)

Terry

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Had a bad experience on a windy day, too. However, the wind was too strong to get back to the field, and my plane was about 1.3km away, still. So I tried to "gently" (while bumpy wind) prepare it's heading and behaviour, although gliding was out of the question. Then I could just watch it going down, trying to figure out where it will touch the ground.

All of that was shortly before sunset, and the next 4 hours we weer searching for it in the dark and didn't find it anymore.

So, the next day with the help of the video we found it.

This was a real lecture to me! :unsure:

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Vallaquest,

I used the Gipsykings CD for this, let me listen to it...The first is only the intro from the Galaxia - 10th track on the CD. The second song is the second track on the CD - Bamboleo. The third on the clip is Volare - the 6th track on the CD.

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