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Hartwig

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Posts posted by Hartwig

  1. cfe7, there are various ways to record our beautiful FPV footage posted in this forum. These are the ones I tested:

    1) DV-Camera Sony DCR-TRV900:

    + Very good, stable, reliable. Absolutely No Dropouts.

    - Expensive device

    2) DV-Camera Canon XL-1s:

    Very good, stable, reliable. Absolutely No Dropouts.

    + Very good, stable, reliable. Absolutely No Dropouts, however, the following digitize process into some editing application might show a few "hicks". Windows Movie Maker seems to be very generous, thus I recommend it for capturing.

    - Expensive device

    3) Hitachi Hi8 Camcorder VM-H71:

    + Excellent, relatively cheap, very easy tu set up and use, robust and usable in all weather conditions

    - obsolete, analog => needs ADV-Converter for further editing and publishing

    4) Laptop with a Canopus Converter ADVC-100:

    + The best I've ever seen! NO dropouts! Excellent picture quality, converts in both ways (e.g. for client monitor during editing), rock solid! Delivers DV-Quality.

    Supported for Avid editing applications

    - Rather expensive, superceeded by ADVC-110

    5) Laptop with an old proprietary AVID Cinema USB-M-JPEG capture box:

    + Great tool and easy to use on Win98 for good and stable video signals

    - Absolutely unsuitable for FPV video recording! During weak signal periods and Dropouts the capture process stops.

    Cheers,

    Hartwig

  2. Thanks a lot for sharing your project! It's amazing!

    I find it very inspiring and the pictures are really breathtaking.

    Just an idea regarding the moisture: is the moisture on the outside or the inside of the plexiglas? If inside (as I suppose), could it be helpful to put some small packets of demoisturizer (the little bags you find it in packings of electronic devices) into the payload, in order to reduce humidity?

    Just an idea, don't know if it works under these extreme conditions.

  3. :-) It is just an idea.

    BTW, I tested Airwave TX612 along with Airwave RX623 and it's great! I had some trouble with the audio which is still not resolved totally, but it seems to be related to the OSD I'm currently using.

    However, I compared the video signals which go into the TX with those that leave the RX on my scope and the combination of AW612 and AW623 is quite good. Of course you see the bandwidth limitation on high frequencies (lowpass effect starting at ~3MHz), but the picture looks quite nice.

  4. Regarding receiver, you might like to think about assembling the following kit, as I do:

    Comtech receiver module:

    http://www.lechner-cctv.com/artikel_einzel...32p1550vl1abd91

    Preinstalled PCB:

    http://www.lechner-cctv.com/artikel_einzel...32p1550vl1abd91

    uC for Channel Selection:

    http://www.lechner-cctv.com/artikel_einzel...32p1550vl1abd91

    This altogether costs roundabout 52EUR and it enables you to select any frequency in the range 2300 - 2555 MHz in 1MHz steps and it's brilliant quality, (the Comtech module works best in the range 2400 - 2483 MHz).

    However, it needs 12V power supply as the Comtech based receivers do. So you will need a 3s Lipo to power it. Airwave on the other hand is satisfied with 5V, you're just stuck with the preselected channels.

    Cheers,

    Hartwig

  5. Thanks to you all for your kind words! :rolleyes:

    I think VRflyer flattened his Easystar's wings because he likes to fly around obstacles and maneuvers like that. In this case it's more agile. so it really depends on the style you want to fly.

    I've seen rudder mods on various pages about Easystar modding, so I think it definitely makes sense, and I would really prefer this to flattening wings and ailerons. For what I want is stability at first and then margin for critical situations. So I will start off with the rudder mod, now.

    -AT-Rob10000: I just love your video! :rolleyes:

    It makes me really impatient to get my new ES ready to take off again!! :D

    I'm looking for ideas how others modified their Easystars to get inspiration, especially on rudders and drive, to provide a good stable basis for FPV flights, even on windy days. (Sorry if I'm going off topics at this point.)

    Cheers,

    Hartwig

  6. Well... I was surprised as well. Actually I think it was more a matter of bad concentration. I was focusing on the field and when I realized that the plane was drifting it was just 2 seconds too late. Otherwise I could have saved it by loop and roll, at least that worked in similar cases before, but at higher altitude.

    Since I don't have ailerons installed I find it a little tricky to get it out of hard positions.

    So in this case it "landed" on the upper side and smashed all electronics of the video and telemetry stuff, and even the fuselage has burst and a couple of centimeters shorter now. I found the transmitter disassembled even without its shrinkwrap and no cover lid on it anymore :blink:

    However, the backup Easystar is downstairs in the cellar waiting to get assembled. So it will take a couple of evenings until I'm up and running again, probably with ailerons ;)

  7. I just hope that there was no static discharge to the wires, as this would grill the chip connected to it.

    I would remove the wires, clean the whole thing very carefully, and make sure you are grounded (for example with a wrist wrap connected well to ground) make sure that no wrong connections were produced by damaged wires, and that the pcb is not bend when reassembling the case.

    I recommend, that you make sure you put the cam in the exact original state (mechanically and electrically) before you proceed with any other investigation.

    Can you send a more detailed screenshot of the cam where you soldered the wires to?

  8. Hi oxxyfx,

    a couple of weeks ago I posted a schematic in the following thread:

    http://www.rc-cam.com/forum/index.php?show...wtopic=1977&hl=

    You can use it for your application exactly the way it is shown there, and use MAX4217 as the OpAmp. The schematic is similar to the circuit shown in the 4217's datasheet on page12, only that you don't need symetric power supply.

    You can forget about the coax cable and the 75ohm resistor on the very right hand side. They are there just to show the entire function. Actually the represent the goggles video cable and it's input cable impedance. So it's not a part of your video buffer circuit.

    Just connect the Airwaves video out pin to the left port of this buffer, where it's labeled "IN", and connect your goggles to the right side of "Rout".

    Use exactly the same circuit for the second buffer, connect it's "IN" to the same node as the first buffer (to the Airwaves video out pin), and just leave "Rin" of the second buffer. The reason is that this is the termination for the Airwaves video output stage which must be terminated with 75ohms, and so it's needed just once.

    Cheers,

    Hartwig

  9. Regarding the video goggles I compared "cheap" i-glasses with 320x240 to the io-display HR versions and found that the resolution is worse, of course, BUT: when your radio signal gets weak or when you get dropouts, the extremely expensive HR-glasses just blank the screen and need a couple of seconds to resync after the signal gets good again, whereas the low res goggles alwazs stayed in tune and showed me the noise when the signal is bad.

    So, because of this fact I chose the Olympus Eyetrek FMD-200 goggles, for I know I can rely on them! You will get them on Ebay.

  10. 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.

  11. For me the most effective way to filter the power line of the video TX when running everything from the main battery is to use a linear regulator. Just make sure that its input voltage stays high enough so it can do it's job properly.

    The video cable between camera and TX should be shielded when it's so long, but I guess you did that already.

  12. I guess that's a normal behaviour. Take a look at this page:

    http://rangevideo.com/index.php?main_page=...4&products_id=8

    "...If more than one channel is selected (up to 8) the receiver will automatically flip between the selected channels in 4 second intervals..."

    I don't know which receiver module they actually use in this device, but it sounds familiar to what you're experiencing.

  13. Another thought comes to my mind, regarding the fresnel zone.

    In the Online Range Calculator (http://www.compex.com.sg/home/WDC.asp) you can see in the last two fields the minimum height clearance and the Fresnel Zone clearance. So maybe the point of better reception is related to the angle at which you put the receiving antenna regarding to the ground. Maybe that clears the Fresnel Zone, better than the positioning on a high tripod with a more flat angle. Just a guess...

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