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Hi Mark, that's great! Please count me in for

- AWM635RX US$ 17 (diversity rx)

- AWM633TX US$ 15 (500mw)

When should I transfer the money? Right now, or later?

Cheers,

Hartwig

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eehh Hartwig, PM means Private Message :-)

I also wrote to him and ordered a bunch of those COOL modules.

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AnthonyRC sent me a message saying the diversities are pretty crud, here is his message:

Hi Mark,

I noticed that you are offering the Airwave Diversity modules for sale.

Just wanted to make sure that you know, these are not really usable for R/C Flight, infact, they perform worse than a standard single receiver.

I believe that they were designed for static installations (door cameras, etc.)

I wouldn't want buyers getting their hopes up. Both myself, and rc-cam have evaluated them, and we both gave up.

Cheers,

-- Anthony

We have not had time to test them so i would heed his advice and go with the 634RX if you were thinking of getting the 635.

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I had read that on a board too and warned Thomas yesterday as well. Pretty deceiving :(

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I had read that on a board too and warned Thomas yesterday as well. Pretty deceiving :(

I miss that, can you direct me where you read this?

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Same as above, it was Anthony relating his experience with them. Can't remember whether it was on here or on rcgroups.

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well the 635 diversity receiver is amazing,

see here indoor test, tx is 1m away with a dummyload on it,

so no real tx antenna.

http://www.webx.dk/rc/video-wireless/635div.wmv

here I have inserted 15mm leads into the sma connectors,

to give as bad signal as possible, and to see if it can switch antennas fine,

I also tried to take out one of the leads later, and then I saw all the normal drop outs from nulling indoor.

http://www.webx.dk/rc/video-wireless/635whip.wmv

here I simply see if it will stay at input 1 or 2 if input is strong compared to the other input,

still the tx is weak, no link after a few more meters !

note the nice nulling in the clip, see that is what happens with only one antenna mounted, just as bad as normal 1 antenna rx systems

I also tried to compare video quality with and without the radio link,

not possible to see any difference.

I have NOT flight tested this diversity 635 RX yet !

I will be back soon..

Edited by ThomasScherrer

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I have been flight testing the 635 for several months now, and made some nice double-sided PCBs for it.

My hope was to be able to offer the AP/FPV community some reasonably priced diversity kits, but the performance really isn't suited to this application, I abandoned the project :-(

When compared against a dual-airwave diversity system, even with the same antennas, it performs extremely poorly.

It is a real shame, on paper they look good, but I think they are better suited to home video RF-links, or video intercoms, where neither rx or tx is moving.

The only reason that I flight tested it for so long is that I mounted it on my goggles for FPV flight. When using it, I use a second dual-airwave diversity system on a tripod to record the flight, the 635 video is 'ok' for close-in FPV work, but I wouldn't want to record the video from it

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but I think they are better suited to home video RF-links, or video intercoms, where neither rx or tx is moving.

But the stupid thing is that diversity is pretty much useless in those applications... <_<

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But the stupid thing is that diversity is pretty much useless in those applications... <_<

Not really... if you happen to position the Tx and Rx in a null, then you certainly need it.

Same reason the WiFi guys have used them for years, to save you from sliding your laptop around on your desk to get a decent signal :-)

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exactly !! diversity is much more important inside your house,

many more reflections and more chances for nullings.

Thanks for telling us Anthony, about the 635.

it is possible they have improved it since ?

mine has serial 000358 on it, and 0539A, any clues ?

I have only tested it indoor and only one unit,

the switching is not possible to see on the video,

we know it works with two LNA and an RF switch before the receiver inside,

so there is only one RX unit there.

I think it works like this: the diversity microcontroller get in sync with the video,

and check if the other unused input is stronger at black levels or just after sync, or picture start, or so ?

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Latest news:

I have now sit and played arround with the 3 receivers I have on stock,

sensitivity comparing on ultra weak signals:

the lawmate I have always used is actually the worst.

the 635 diversity is better, but at really weak signals its sync system fail,

and a white switching stribe rolls down the screen,

at that point only noise is to be seen on the lawmate rx,

the 634 rx has the best sensitivity, slightly better than the 635

and no stribe problem at weak signals, ok noise that is normal :-)

I still think the benefit from diversity is worth a few field test,

so I have planned to go flying and recording a bit tomorrow,

one Patch pointing up, and one vertical whip pointing up,

my TX antenna also points up, so I hope the drop outs I always have when approching to landing from the horizon will be removed or better,

we will see.. I'll be back.

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exactly !! diversity is much more important inside your house,

many more reflections and more chances for nullings.

Thanks for telling us Anthony, about the 635.

it is possible they have improved it since ?

mine has serial 000358 on it, and 0539A, any clues ?

I have only tested it indoor and only one unit,

the switching is not possible to see on the video,

we know it works with two LNA and an RF switch before the receiver inside,

so there is only one RX unit there.

I think it works like this: the diversity microcontroller get in sync with the video,

and check if the other unused input is stronger at black levels or just after sync, or picture start, or so ?

Thomas,

I looked at my 635s and didn't find a serial number. Was yours on the outside of the can?, or inside?

-- Anthony

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Hi Anthony

see here is the test board I made for the 635:

635-board0005.jpg

See the label on top of my 635 :

635-board0004.jpg

I guess it is a date code or serial number.

for more files about the 635 rx and board layout and so on, go into this filder:

www.webx.dk/rc/video-wireless/

all 635 files, start with 635 :-) so they are easy to find

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We did flight test them and were not impressed, the quality was not as good as the 634. Our video, pcb design and photos of it all are with airwave's engineers at the moment. Will be interesting to see what they suggest/say.

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Considering the potential quantities that would be used by the AP/AV/FPV market, I think I know what they will suggest :-)

It does seem that our application is much more demanding, and quite different, than that which they were designed for, but lets hope they come through with something.

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Well if they say that our stuff is all correct and they are just plain not designed for this, i'll ask them to get their ass into gear and design something for it!

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for more files about the 635 rx and board layout and so on, go into this filder:

www.webx.dk/rc/video-wireless/

all 635 files, start with 635 :-) so they are easy to find

A little bit off topic, I saw on your website few pictures of a lna on the patch hand, how did it work?

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