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Hartwig

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Everything posted by Hartwig

  1. Check your TX's RF output lead to the antenna. I had similar behaviour once. In my case it was a broken lead but very tiny small break which I c ould hardly see with bare eyes. soldering over it solved the problem quickly and effectively. Well, it had a crash before, so that's where the damage came from.
  2. Hi jbourdon, in this thread: http://www.rc-cam.com/forum/index.php?show...wtopic=1222&hl= you can find information about some easystar setup. Something about motor mount: http://www.rcgroups.com/forums/showthread.php?t=566537 Another nice page is this one: http://www.mpx-easystar.de/ It's a german page but it should be easy to understand the most important things. http://www.rc-cam.com/forum/index.php?act=...ID=in&MSID=4371 ...and this one might answer some of your questions: http://www.rcgroups.com/forums/showthread....iloting+project Cheers, Hartwig
  3. To me it looks like your video RX does not match exactly the frequency of your TX. It reminds of a a satellite receiver being mistuned. This would also explain the dropouts with the different recording equipment. But this is just a rough guess, I might be wrong.
  4. I did a few tests more and I'm currently using a 6,3x3 Slowfly Prop on the AXI 2212-12 which seems to be a good compromise between Power and current. It draws about 10A on a 2-cell LiPo while the Easystar is still controlable without too much interaction, and there's still some Power left to fly on moderate windy days.
  5. Hi Wavess, I haven't tried them, yet. I'm currently using Schulze, MZK and Hitec. But ACT has great references, for example Peter Michel uses their diversity system in his large planes: http://www.michel-concorde.de/index2.html
  6. Wavess, if I can help just tell me. I'm german, so I can translate regarding the ACT or the like.
  7. And another one, showing the waveform of a so called "Multiburst" signal to verfiy the frequency response / bandwidth of the transmission:
  8. Hi Doofer, the syncs need to be in "good shape" and the video levels must be correct, that means from 0V to 1V absolut range, not more, not less. (a little overhead of up to 0.2V might be tolerated by most devices, but that is not a "Must". However there must not be a DC offset, and the video level of black must not be lower than 0.3V! Otherwise it will screw up your syncs.) You might like to take a look at this page for a simple example of the video waveform (vid_wf.jpg) : http://www.rc-cam.com/lawmate.htm As a real life example, I attached a pic that shows the waveform of a black scre
  9. Looks like this: However, the plane glides very nicely, but when I turn on the motor it goes up and I have to push the elevator hard down to compensate. Despite the fact that I increased the mounting angle of the motor, it still goes up very much, so I guess this won't change unless I reduce power
  10. Hi, I put an AXI2212-12 with an APC7x5 thin electric prop onto my Easystar, and this makes a lot of thrust, and the battery's empty pretty soon ;-) The motor is mounted in the fashion of rob's mounting:
  11. This is hard to judge without a look at the signal's waveform. You could try the following instead: 1) Place the camera in a dark room or just put its lid over the lens to cover it and see if the the strobe effect still occurs. In comparison to that vary the amount of exposure up to bright day daylight and see if there are any changes in the amount of strobes. 2) However you might like to try another camera with your TX/RX setup as well, for example the AV-out of a camcorder. 3) Put the video amp/splitter in series between the camera and the transmitter and play around with the levels.
  12. Is there any way to determine if the pot of the frequ Synth PLL is still correctly adjusted? I'm not sure if I accidently touched the wrong pot today and turned it back into its previous position... How does this pot affect the PLL?
  13. Do you have a schematic or a block diagram or a pict of your setup (signal flow overview) which you can post?
  14. Ah, great! Thanks! Do you have an idea what the other pot in the upper left corner is for? I actually supposed it would be this one because it's accessable from the outside Cheers, Hartwig
  15. I got two brandnew identical Airwave TX612 modules which perfrom very well, but I got one problem: They have different sensitivity on their video input. While using the same receiver I get a little less than 1Vpp with the first module and about 1.1Vpp with the second. I heard rumors that the video level sensitivity of the modules can be adjusted using a little pot located inside the "sardine can". Does anybody know if this is correct, and if so, how to locate that pot? I don't want to screw up the precious thing by destroying a factory set parameter. On the picture, which I attached,
  16. Exactly. I would strongly recommend to apply the seperate vreg solution. This will definitely get you out of trouble, even when your power source gets weak or messed up with other stuff. You can also add another servo, if needed. Just power it from the servo supply. Doing this with only one vreg, would most likely show up with distortion again because the passive filtering might not keep up with the higher current.
  17. I remember I once saw a 2.4GHz TX/RX set on where the receiver had a pot to adjust the frequency. You can find them on Ebay. In its documentation they say that the frequency shifts with temperature and that you have to readjust the receiver then. I would recommend to go for another set, check out airwave and friends
  18. Just a little add-on: The switching regs of Dimension Engineering are great from my experience. However if you should have problems with interference, you can try adding a few low capacitance caps as well because the big cap might be too sluggish to compensate the high frequency components of the reg's switching. I tried the DE-SW-Regs as a BEC and my RC-receiver just refused to work. The "Filtering-method" with the linear reg, which I described before, solved the problem.
  19. Of course, if the signal is already terminated on this side, no second termination should be applied. You can daisy chain quite a couple of video devices, just make sure the first as well as the last device of the chain is terminated with 75ohms. For example, a camera has an output impedance of 75 ohms at its video output connector. So when you connect it (for example) to a Monitor, the Monitor needs to have an input impedance of 75ohms to perform proper termination of the transmission line. You can hook up another device between the camera and the monitor as long as this device has a high
  20. For what I suppose those receivers have comtech modules inside which need a certain voltage to operate properly. If the circuit which the manufacturer designed permits, it might be possible to go as low as ~8V. The standard circuit at the moment requires more than 9V since there is linear reg for 9V output which supplies the audio demodulator IC, as well as a couple of other components. So this might get difficult then. However, it seems that the comtech modules themselves seem to operate at voltages below 9V, as long as the voltage at the VCO power supply pin is high enough to ensure proper
  21. Matt, regarding Op-Amps, single supply and DC-Bias and so on, I posted a sample schematic which might be useful for you in the following post: http://www.rc-cam.com/forum/index.php?show...wtopic=1977&hl= Cheers, Hartwig
  22. Actually I didn't want to chime in, but now I must say that from my point of view there might be some misunderstanding regarding wallaguest's reply. I guess wallaguest posted this picture to show that it's possible to mount this type of lens to this specific camera, while from my experience, the lenses of this type differ in the position of their thread. The camera looks very similar to one that I have, and mine is a CMOS type. So that would explain the problems regarding exposure-changes. A CMOS camera will not perform as well as a CCD type when pointed into sunlight and then back to dark
  23. In case you like a shortcut solution, you might consider the MAXIM-ICs "MAX7461 Loss-of-Sync Alarm" and "MAX4311" or "MAX4314" (High-Speed, Low-Power, Single-Supply Multichannel, Video Multiplexer-Amplifiers). There is a thread in this forum regarding a diversity receiver solution where a similar technique is required. You'll find the thread here: http://www.rc-cam.com/forum/index.php?show...topic=1324&st=0 At the maxim-ic homepage you can easily order a couple of samples for free (limited quantity per person). If you need more samples of one special device, just ask your friends,
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