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ThomasScherrer

Audio track as modem data NMEA

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Well, just finished my modems and they work nice,...so.... just want to say thanks to DZL and Thomas for these little wonderful toys. :D:D:D

Gil

Edited by Gil

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Gil,

Can you share your setup details for the good of the group? Did you use a filter cap on the receiver? What component values did you use? What brand of Video TX/RX are you using?

I just finished installing the last of the Beta modems into my UAV and ground testing. I'm not using a filter cap in the RX and I'm using the standard component values of the kit. I have a Black Widow AV setup (Lawmate) with a 600mW 2.4GHz TX and a simple standard RX (I'll use my high gain diversity system when I flight test).

The video is clear and the telemetry seems rock solid. When the morning fog condition lifts, I'll be able to do some testing in the air. My long range ground testing of a couple weeks ago tells me I should have no problem in the air.

I'm taking a photo of the finished RX so I can annotate it with Photoshop to help the kit builders. Good luck guys and yes, BIG THANKS to DZL and Thomas for the brainpower.

Jeff

post-6-1179464382_thumb.jpg

Edited by jparisse

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Hi Jeff, I received my Beta Kit yesterday here in germany.

Just to confirm that everything went fine with shipping and customs, in a reasonable timeframe :-)

Cheers,

Hartwig

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Received mine too here in spain. It´s going to take a while before I could try it due to very busy with work.

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Gil,

Can you share your setup details for the good of the group? Did you use a filter cap on the receiver? What component values did you use? What brand of Video TX/RX are you using?

I just finished installing the last of the Beta modems into my UAV and ground testing. I'm not using a filter cap in the RX and I'm using the standard component values of the kit. I have a Black Widow AV setup (Lawmate) with a 600mW 2.4GHz TX and a simple standard RX (I'll use my high gain diversity system when I flight test).

The video is clear and the telemetry seems rock solid. When the morning fog condition lifts, I'll be able to do some testing in the air. My long range ground testing of a couple weeks ago tells me I should have no problem in the air.

I'm taking a photo of the finished RX so I can annotate it with Photoshop to help the kit builders. Good luck guys and yes, BIG THANKS to DZL and Thomas for the brainpower.

Jeff

Hi bud, here is my flight equipment and my last plane project,....if you ask me for cam´s, Tx, or other things,....too many... i´ve owned and still have,....., since i started implementing airborn cams on my remote planes ! :rolleyes:

cheers

ground%20station.jpg

uav1.jpg

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Actually Gil, we are only interested in the set-up into which you have installed the DZL modem. This thread is for DZL users who wish to share information on the DZL modem and how it integrated into their plane. I bet most folks on RC-CAM have planes with cameras in 'em. :rolleyes:

I must reason that the DZL Modem works perfectly for you without any modifications.

Great... so far 100% success.

Jeff

Edited by jparisse

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:o I´m sure.... most people have cam´s in their planes ;) and not many have DZL modems,...oh well.....i thought about share my flight setup with PDA & DZL modem,....sorry for having display it in here.

Yes, the DZL modem is the standart version as Thomas show us here and is working fine !

P.S - For the modems, i´ve used Pony Prog ( latest version - free program ) with an AVR programmer (cheapo from ebay ),....., i´ll be making some upgrades to this modem and 2 new boards for telemetry and OSD.

Total for the 2 modems finished = +/- 40 euros ( Attiny2313 + programmer + electronic components ).

Not bad,...., cool price for a cool toy. :D

Gil

Edited by Gil

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40EUR=$54 about the same as a full DZL Beta kit with case, PCBs and all the parts. You're right, Gil... A bargan!

Jeff

Edited by jparisse

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:D Yep,....., and that, thanks to Thomas and DZL,...., listen.....if you take the 28 euros out of the equation (AVR programmer),...., you´ll get a very cheapo modems ! :rolleyes:

I have more applications with AVR´s running on my workbench at the moment and i really needed the programmer !

Tell me,...what GPS program are you running on your PDA ? :unsure:

Gil

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I c,...me too,....on my desktop ! ;)

Gil

Edited by Gil

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I run Google Earth Plus at home to survey the flying field and to cache the data so that when I'm away from the Internet the maps are still available. I use a laptop for telemetry and one of those portable 7" DVD players that are also dirt cheap on EBay for video and OSD data. I setup my gear inside the rear hatch of my car.

My current ship: http://www.rcgroups.com/forums/showthread.php?t=631757

Jeff

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Hi , I receive it yesterday , I going to plug my soleder Iron.

But just a thing , where is the scheme to mount the kit , you forgot to put it in the box ?

Maybe there is a web page I've don't see.

I'm happy to test the modem soon..!

:rolleyes:

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Taz, you can the schematic from here ! <_<

http://dzl.dk/projects/electronics/modem/modem.html

Jeff, nice project you´ve got there,...., the old telemaster still is a nice platform for this kind of experiments,...., i´ve noticed that we share the same toolbox(very helpfull and easy to transport),......, my congrats on your project ! B)

Gil

Edited by Gil

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Taz and Beta Team...

The schematic and construction photos can be found on this thread. I wanted to keep everything here during the testing phase so we could all research this together.

Thanks Gil... yeah, I love those plastic toolboxes from Stanley Tools!

Jeff

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Testing with Airwave

I finished assembling a 633 TX and 634 RX from Airwave and tested the DZL Modem with them.

Video looked clear and very much like the Lawmate product. The difference (as Thomas has already pointed out) is in the quality of the audio link(s). The square wave looked almost identical to Thomas’ screen shots and the TX tolerated a much wider range of pot settings. I added a .01uf, .1uf and 1uf filter cap just to see/hear if I could detect any difference or benefit. Maybe in a harsher airborne RF environment a filter cap could ground out LF but on the bench, I couldn’t see how it helps.

Jeff

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so Jeff that means = perfect ?

lets hear about some test flights ?

I have experiance about some stuff looks really good on the bench,

but could be different in air. so go flying dudes :-)

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The modem is probably perfect but the audio fidelity (antique word) of the 650mW Lawmate TX is not so good...

I flew a test today with the DZL Modem and above mentioned Lawmate TX. I should point out that I have messed with the audio pot on the TX so much that the screw driver slot is worn down. I think this pot is for impedance matching but on some TXs (as Mr. RC-CAM points out) is a carrier frequency adjustment for the audio channel. In either way, I used it to maximize the performance with a TinyTrac3 and, later, with the DZL Modem (less so). The “non-factory” setting of this pot may skew my results as reported herein. Also, I flew at a soccer field the Port of Los Angeles at Long Beach (one of the busiest sea ports in the World in one of the largest cities in the US) so R.F. traffic was very dense.

I created a 5-mile GPS route for the plane to follow and used a laptop with cached Google Earth data for moving map visualization. The route was plotted over a 15 acre field with the plane staying within 1000' (305m) of the RX. The route took 20 minutes to fly and I had one loooong (5 minute) data drop out that wouldn't reset even with a power cycle of the DZL RX. The lights on my serial port adapter (my only TTL diagnostic tool at the field) blinked away and I restarted GE+ with no positive effect. The data stream restarted, by itself, a few minutes before I landed.

I plan on switching over to the Airwave products to see if I get better performance ( like Thomas B) ) so wish me luck. BTW are there any commercial products build around the Airwave modules that Intelligent Flight AU sells? They seem to work well, are well supported on this forum and priced right (thanks Mark) but I am curious about a factory built and tested unit...

Jeff

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did you check the GPS data was setup so that some minor holes exist in the datastream ?

the DZL modem encoder need this to re-sync if failure out of phase sync due to a signal glitch.

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Thomas... You are like the Shaolin Priest from the old Kung Fu movies! Totally wise but cryptic to your followers! :ph34r:

I have two sentences setup: GGA and RMC each at 1Hz so the data seems continuous to this human processor. I understand about the pauses but don't understand how one can program the GPS unit to produce them... Should I just lengthen the pause time between the sentences I am currently using (say 2 or 3Hz)? Is it that easy?

Thanks for teaching me so much. Someday I hope to snatch the pebble from your hand... :D

Jeff

Mark... That is VERY cool and about time (ask 'em to make a 1000mW).

Edited by jparisse

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im starting to put my plane back together. i have a dzl modem. i have few questions. what is the voltage do i use to power the dzl modem. and for the gps input. i have a geko 201 that i am feeding my osd with. which two wires do i need to feed the dzl modem out of the gps. i have red black white and brown coming out of the gps. thanks

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DZL TX takes 5v which you can get from your RC RX. The GPS connects to the lower of two connector (connectors to the left) with just GND and TX lines (black and yellow).

Jeff

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Jeff, if will not work if you dont have tiny delays in the datastream,

it is impossible to see using a terminal,

but easy to see if the data is sampled with your PC audio input,

just record 2 sec, zoom in and scrool back and forward,

you will then see the delays between the pakages,

at least 2-3 chars needed, more is even better.

I dont know your GPS type but most of the GPS modules we normally use can be configured to send some pakages at slower rates, leaving spaces for re-sync,

the phase modulation the DZL model encode and decode MUST have those spaces,

if no spaces it actually works in the lab, but on the plane you will get short drop outs or other noise glitches, this will in some cases be counted as a data pulse, and then all following datapulses could be inverted, that is why you need a clean space to resync, if this space come every sec, you will get a fast re sync and your overall good data will be much better.

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