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Everything posted by Dimitris76

  1. The tracker is not 100% reliable yet but I am getting there. I have two pots to play with now - Lynx' and Pyle's... Hehehe Thank you for your help! /Dimitris
  2. Thomas and friends, I just checked the "setting write protection" box on MiniGPS and pressed SET. The module is starting now at 1hz... How do I undo that? I need GGA, RMC @5Hz, 9600baud as default... /Dimitris
  3. Thomas, I am starting to believe my problems were related to the 6m long cable... Since you posted your instructions I am running the video signal first through Pyle amplifier then send it back to the tracker. The idea is to boost and condition whatever quality of video signal the diversity receiver is sending out, before I send it to the tracker's circuit board. I wanted to reduce the clutter so I figured that a single 3x RCA AV cable would be enough for all this - yellow from VRx to Pyle's input, red from Pyle's output back to Lynx tracker, white for the mono audio channel. That's what I did with a 1 meter long AV cable and it was working very stabile but I didn't like the idea of placing all this stuff on the car's roof (next to the tracker), so I tried once more the 6m cable with the thick video coaxial. Same... the tracker was not working. As a last resort I tried a 10 meter cable I had lying around - the cheap kind, the one that has thin 1/8" cables on all three RCAs. And it worked!!! I went to the store's website: http://www.clasohlson.com/se/Anslutningskabel/Pr321228000 and read Skärmad: Nej in english - shielded: No So apparently despite the fact that the video cable is much thicker and stiffer that the audio channel cables - the braid is not soldered on the RCA coonector's ground and that makes all the difference in the world in my application. /Dimitris
  4. This reminded me a conversation I had with Ian another hobbist that modified the original Lynx according to attached schematic. Then I looked for his old email and I quote: "I then hooked up a DakarOSD board and attempted to get data to the Lynx. However, I got nothing. Then I remember that I had a problem with Cristobals original design and so I modified the circuit a little. If you look at the Lynx schematic on my web page you will see 2 resistors and an extra capacitor at pin 3 of the LM393. This modification fixes a problem when the video signal has a large DC offset......which some receivers can have. My modification AC couples the input so that any DC offset makes no difference." I have this mod in my Lynx too. Is it possible that LM393 IC is providing 75 Ohm termination via pin 3? Could this modification on Lynx be the reason of my problems? /Dimitrios LinceIJV2.1Schematic.pdf
  5. I went over the RCA socket solder pads. Still the same. I am giving up... /Dimitris
  6. Here is what I have noticed when I tried once more the 6m long cable. When I slightly pulled the RCA connector out of it's socket the tracker came to life. I was excited and I believe now the problem is just a case of a sloppy rca socket or a cold solder around it.
  7. Ok I found a 98 Ohm resistor and did Step 4. Still no go. The tracker dies as soon as I replace the short cable from Vtx to Pyle's input with a long one. /Dimitris
  8. I followed you instructions: Step 1: Done Step 2: Done - connected with 1 meter long cable Step 3: Done - connected with 1 meter long cable Step 4: Skipped Step 5: Skipped - I didn't have to adjust anything - read next step. Step 6: Everything is working like a charm. A solid LED on the controller and a perfectly functional antenna (tested indoors with a NMEA generator program). Step 7: Vtx to Pyle input cable replaced with the 6m long one. No go... Tracker freezes. Is this because is skipped step 4? I am trying to measure the resistance in Pyle's input and it's infinite according to my multimeter.When I switch up to 200k scale it shows 50 and then it drops to zero...I am lost here... /Dimitris
  9. My Lynx controller's board is posted as .pdf file on post #1. Here is a block diagram of what I want to accomplish. The problems occur when a long cable is being connected between the Lynx and Pyle amplifier. If Pyle is not properly terminated, can't I just solder a pot across it's video input and adjust it accordingly? /Dimitrios
  10. Here is how the RCA connectors plug on the tracker's circuit board - a straight passthough as you see. /Dimitris
  11. You were right about the long cables Thomas! I just used a much thinner but also much shorter - only 1m long - cable between the tracker and Pyle amp and the problem went away. It's a viable solution but I would really like not to have the Pyle amplifier on the car roof next to the tracker. The whole point is having only one composite video cable entering the car and then have the amplifier to distribute the signal to various devices. So, how can I eliminate this "ringing" on long cable runs? This 75 ohm impedance - is it something I can measure with my multimeter and adjust with resistors between signal and ground? /Dimitrios PS I am attaching photos of my "Good" quality 6m long cable that I would like to use between tracker and Pyle and the ratnest on my desk just to give you an idea... hehehe
  12. If you look at the schematic, there is no specific video output and input on the Lynx tracker. Input from VRx and output to monitor devices, DVRs, video amplifiers, etc is common and in parallel. Could these long cable runs throw something off? /Dimitris
  13. Ok more info. It seems that the problem is not Pyle-specific. I connected the tracker with the same long video cable - about 15ft. long real coaxial - straight to DVR video input and had the same problem. The antenna tracker freezes and does not resume unless I unplug the cable. Then I tried another composite video cable - longer and thinner - in case it's the cable's problem and the same thing happened. When I connect a Philips 9" monitor I have straight to the tracker I have both picture and a working antenna... /Dimitris
  14. For quite some time now I have been using a home made antenna tracker based on DakarOSD and Lynx tracker controller plans. http://www.aeromodelismovirtual.com/showthread.php?t=1849 Recently I thought it would be nice if I upgraded my ground station with DVR and an extra LCD monitor apart from my goggles so I put to use my trusty Pyle 4 channel video amplifier. The tuning procedure is to adjust the R8 multiturn potentiometer (see attached schematic) until the LED lights almost solid, meaning that there is a steady flow of decoded data coming out of the Lynx antenna tracker controller on the ground. I do that and get a solid light over VTx/VRx link and everything works wonderfully until I plug in the RCA cable that goes to Pyle amplifier. As soon as I do that the amplifier the LED turns off and the tracker's operation is interrupted. I turned the pot in every imaginable direction without success. The LED turns on and the tracker resumes it's function only when I disconnect the cable to Pyle amplifier. Does the amplifier introduce interference? Is it some kind of impedance mismatch? Thank you in advance, Dimitris PS I am even attaching a .pdf my version of Lynx board LynxBoard_v1.3.pdf
  15. Oh... I was hoping to hear that a sacrificial diode or something would be damaged... Thank you for the answer! Dimitrios
  16. Yeah, with that I lost my last chance for FPV flying this weekend...
  17. I thought it happens only to others but while I was testing a new FPV setup I reverse-connected the switch-mode BEC I am using for powering up everything with 5V. The BEC is this one http://www.dpcav.com/xcart/product.php?productid=16488&cat=252&page=1 . I heard a faint "paff" and it died immediately. I don't see any obvious damage on any component. Can anybody tell me which component did most likely get damaged, in order to replace it? Thomas? Regards, Dimitris
  18. The board's behavior is still a mystery and having troubleshot the hardware part as much as I can, I'll blame the software for now and call it a day. My crude solution is this: sorry for the blurry photo - iphones are not real cameras... which is a delay circuit based on a 555 IC and a relay, that powers up the servos after a 1.5sec delay - enough for them to "miss" this jolting phase. I might sit down and etch a proper PCB for this add-on card someday as I hate perfboards, but for the moment it works! Dimitris
  19. I have been in contact with Ian. He is describing the problem as random quick movement within normal servo range. He using a servo slow to take care of it.
  20. Fuse settings? What is this? I have used that little program that comes with PICkit2 and I have not been asked at any point about fuse settings. I just clicked "open", browsed to the hex file and then clicked "write"... Did I miss something? Dimitris
  21. About the video: I was about to power up the servo with the ESC, with common ground to the Lynx and holding the signal cable straight on the bent out pin 22. But before I power up the Lynx I have noticed the glitches due to my hand moving around. The photo is old - I have populated the board with all the caps and then some more. The 7805 on the top right though has a it's 0.1uF ceramic staight on it's output but the GND is a little further away... Dimitris
  22. What do you mean "will ignore unusual R/C pulses"? Will it ignore and let them pass through to the servo or ignore the incoming out of range pulses and replace them with the minimum/maximum allowable/normal pulse length (0.8-2.2ms)?
  23. Certainly, here is the schematic: http://aeromodelismovirtual.com/attachment.php?attachmentid=8320&d=1248365157 and the only addition to that is a MAX202 RS232 driver (with 4x 0.1uF capacitor per datasheet) connected on data out (pin 17) The power supply is with two 7805 regulators (one for servo mechanics and one for the tracker's ICs) with 330uF electrolytics at input/output plus 0.1uF at various other points along the output (one right by the PICs power supply pins). Dimitris UPDATE: I have powered the servo through an ESC and observed some interesting behavior: http://s12.photobucket.com/albums/a235/Dimitris76/FPV/Lynx20b%20Antenna%20Tracker/?action=view&current=EMIlynx1.flv I don't even have to touch the brown signal cable and it brings the servo violently to it's mechanical limits !!!!????
  24. Thomas, unfortunately I don't have a scope. Can one of these software soundcard-based scopes be up to the task? The RCFS-V2 with it's out of range pulse rejection could indeed solve the problem. Does the Landtastic let any out of spec servo pulse go through - even if it's under 0.8ms or over 2.2ms? Another solution would be making a small auxiliary circuit with a 555 and a NPN transistor to power up the servos with a few sec delay! Dimitris PS Just bent pin 12 (the LED's pin) out of the socket and tried it... same S@#%!
  25. i just went out and bought some 2.2k resistors. I have already tried with a 220ohm one and didn't help at all though... I am seriously thinking building your Landastic in order to slow down things a little and hopefully avoid hitting the servos mechanical limit. Less strain to the tracker's mechanic is an extra bonus too! Alot of people are using the GWS 360degree winch servo for panning. I don't know if they test the setup without the antenna's weight but they don't report this glitch. Dimitris
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