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About KeithLuneau

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    RC-Cam Regular
  • Birthday 08/18/1982

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    On top of the world! (in Louisiana)
  1. Hi Thomas, I just wanted to thank you for this project. I've made one up for myself, and it works great! I grabbed two board from RTFQ (KV-Team modded ones), but I don't have access to a 3D printer so I put the boards together and made some simple cables to adapting them for my needs. I simply soldered all the pins as standard, added the jumper wire for the voltage sensor on both boards, then soldered a JST power lead to the back of the 12V and GND pins. After a bit of glue for a strain relief on the power leads, I shrink wrapped the board with clear wrap, so I could see the LEDs and also the marking on the boards. (I maked them Tx and Rx, so as not to confuse them later) On the Tx board, I left both pins for video in and out, in case I ever re-purpose the boards later. On the unused video in pins, I just covered the pins in colored tubing, makes a nice reference when I plug in a cable to the other set of pins. To test the boards after flashing the firmware, I simply used a male-male servo lead and plugged from the output of the TX board to the input of the RX board. This also carried power between both board so they were both powered by one small 2-cell lipo. They matched up well and passed fine to me, at least to my eyes. Test pattern shown below... When using them to test my video transmitters, I simply plug in a transmitter to the Tx board. (all my transmitters are wired with servo plugs, so it worked out perfect!) I power the test board with a 3S lipo, which also powered the transmitter plugged into it. On the Rx board I made two of the adapters like the one in the picture, RCA type to servo connector. It goes inline between the video receiver and my monitor. This board is powered by another small lipo, separate from the power for my receiver/monitor. So far I've tested 6 video transmitters. All of them 1.2/1.3GHz ranging from 200mW up to 1500mW, from various sources. (US FPV shops, Chinese resellers, etc.) Only ONE of them was set correctly "out of the box", coincidentally, it's the one transmitter that's always seemed to give me the nicest video and audio. We're onto something here! lol It's worth noting that the 200mW transmitters I have do not have a pot for setting the video levels. Both of them are close, but not perfect. I have 300, 400, 800, and 1500mW transmitters that DO have pots in them. The 1500mW (Gold cased "budget" transmitter from RMRC) was the only transmitter that didn't need to be tweaked. As far as my receivers, I have two tan cased "Racewood" type. One from your store (DPCAV), and one from RMRC when Tim was selling those. I remember a note on your store saying that your transmitters and receivers are checked and verified before shipping, so I used that receiver as my starting point. I checked all the transmitters using that receiver. Once I was finished setting them all, I tested them again with the other receiver from RMRC. All of them were still good to go, so I'm guessing the receivers are matched up well. I use them both on a diversity setup, so that's good to know. I'm looking forward to flying some of these again soon to see how much better my video looks, if any. I've had less than perfect video from some of these planes with these receivers in them. I suspect they will be better now. Thanks again! It's also interesting to note, look how much the voltage varies between the two boards. (8.1V vs 8.4V) They were both powered off the same 2S lipo for that test. It was showing 8.4V on my meter.
  2. KeithLuneau

    Multiplex Twinstar II Build Blog

    Looks great! You shouldn't have much trouble spotting that one in the tall grass should it ever go down... That's brings me to my question, what paint to you use to paint Multiplex foam? I can't find anything that sticks well and doesn't flake off. I'd like to find a nice flat or satin black for the nose.
  3. I remember seeing his flights too. Last time I talked to him he said he was still flying but not posting as much. That was at least a year ago though. I found his site again, but didn't see much about his setups and equipment, at least the R/C gear. Maybe I'll just stick with my current mile range and enjoy that for a little while longer, and work on other things that need attention, like my ground station, a video splitter, etc. People often say how cool it must be to live in the middle of nowhere like I do, with miles of nothing in all directions. Don't get me wrong, I do love it, but it does get boring flying around in the same little circle with all this terrain begging to be explored from the air! lol
  4. Ideally I'd like to fly around 5 miles reliably. I think this amp would give me that, I'm getting at least a mile with stock gear. Given that this costs $120, runs the risk of shooting someone else down (though there's literally nobody flying R/C here but me), is illegal, etc. I think I'd be better off saving up for a UHF system instead. I'm currently using a Corona RP8D1 receiver in one plane, and a Hitec Electron 6 in another. Maybe I'll pick up a good Futaba receiver to try in the mean time. Any suggestions on which one is the best? I do have a PCM transmitter (9CAP) but would prefer a PPM receiver. I like knowing that my signal is weak before it's dead.
  5. I recently saw a link to this amp posted at RCGroups. http://www.cnchelicopter.com/servlet/the-1639/Booster-system-SA725-Signal/Detail The seller claims it's a 7W amplifier for 72MHz, and provides instructions for installing it into an R/C transmitter. I know this can open a big can of worms with regards to the legal issues, and rightfully so. There's probably a long list of reasons why it shouldn't be so readily available for purchase and use in the US. That said, I wanted to ask about it in a technical sense. How well would something like this work? Assuming the receiver side of the plane is properly set up and was performing to reasonable expectations, would this amp make a big improvement? Would it be reasonably safe to use out in the middle of nowhere? (no other R/C activity within 20 miles for example)
  6. I asked this same question on RCGroups already, but more input can never hurt. Besides, I like how answers over here tend to be more fact that opinion! lol I was just wondering if the 5V regulator that's in the cable that comes with the 500mW 2.4GHz transmitter can handled the extra load of a camera as well as the transmitter. I took the regulator out of the plastic housing and soldered my own cables and connectors to it, then covered it in heat shrink, so it's a lot smaller and lighter than before. I've used it to power the transmitter for a handful of flights and it seems to work just great. That was with a 12V camera. I'd like to move the transmitter to another plane with a 5V camera, and it would be nice to use one regulator. The regulator in the plane is one I made using a linear 7805, and it runs about as hot as I'm willing to push it with just the camera. I did mount a little aluminum plate to it to cool it, but it would be much simpler to use the Lawmate regulator if it'll handle the load. Just wondering if anyone has tried it, or could offer some ideas as to how much load it can handle. Just to be sure, this is the cable I'm referring to, the regulator is on a little board inside the plastic at the end. http://hobbywireless.com/cart/index.php?main_page=product_info&cPath=25&products_id=150
  7. Ok, that explains why it's so easy to "tune" the output frequency too then... To quote some info that came up with a search for VCO Transmitters... I guess the final verdict is that I'll never be able to get it to work on a legal HAM frequency within the specified voltages. I did try earlier raising the voltage up to 11.5v and never got it all the way to the next channel on the receiver. I'd have to jump 5 channels to make it to a legal one.
  8. Here's the close up pictures... There's not a lot there... The coin for size reference is a dime. Maybe you can make more sense of it than I can. All I see is poor construction and design! Maybe later today I'll do some ground range tests and see what it's doing with such a low supply voltage.
  9. No, there's no Vreg in the cable now. There was one, but it was a 5V for the little CMOS camera. The transmitter was fed the full 9V from the battery. There may indeed be one on the transmitter, I'll take a look and see. I know varying the voltage definitely changes the freq. it's transmitting on. Using the pot on the Anyvolt I was able to "tune" the transmitter so the receiver picked it up. Tomorrow I'll cut the shrink wrap off and take some pictures of the transmitter board. It's super small, no can, just a little board with a whip antenna. I soldered a short lead with a connector so it will plug into my other harnesses in my planes. If I could use it on 5V it would be great, as small as it is and using such a small amount of power, I bet it would be safe to power it and a small camera off the BEC in a small plane. I'm afraid I'll never get anything close to a legal freq. at 5V though.
  10. A few years ago, I picked up one of those cheap-o cmos cameras with built in transmitter like the "Hong Kong Camera" project. Mine was sold as "1.2GHz", has a tuning knob on the receiver, typical junky set. I messed around with it a little bit for a while, and found that the frequency seemed to drift as voltage changed. I've used it all the way up to 12V, even though it was originally set up for a 9V battery. Using a stable voltage (Anyvolt Micro) I was able to get it tuned so that the knob didn't need to be adjusted much in flight, and made a GPP scaled for 1.16GHz as stated in the project here. I did get a handful of flights in using it, thought I wouldn't go so far as to say that it worked well. I ended up taking the transmitter out of the camera and rewiring it to use an external camera and mic. It's just been sitting around, worthless. Not long ago I picked up a 1.28GHz set which included a receiver like those from Inesun. I decided to see if I could vary the voltage on that little transmitter enough to "tune" it so that the new PLL receiver would pick it up. With the input voltage for the little transmitter between 3.4V and 5.6V, I can set my receiver to channel 4 and it picks it up, the picture looks great, sound is clean too. Channel 4 is 1.080GHz according to the manual for the receiver. That's a problem, it's not legal in the US. I want to try to tune the transmitter to another legal frequency and see if it'll work. Even at 12V it never got so much as warm. So my question is this... Does the output RF power vary as the voltage changes? I don't want to go over 12V and burn it up, but at the same time I don't want to stay too low if it's cutting the RF power too much. I don't ever expect to get a "good" result from this, just playing around with it is all. At most I might stick it on little indoor flyer or something to poke around the yard with when it's dead calm. The transmitter barely weighs a few grams.
  11. I ended making a flight at sunset again today, landed after dark in fact! That was scary... lol I made two trips out to known points just over a mile from the launch point. Video was rock solid the entire time. I used my laptop and Easy Cap, which worked great for the whole flight. I guess I'll just chalk this up as an incompatibility between the Lawmate receiver and my Mini-DV camera. (It's a Sony DCR-HC40 for anyone else wondering what camera it is, might save someone else running into the same issue.) For now I'll also assume that the video levels are probably off and could use some tweaking, and likely pick up the o-scope and find out!
  12. For what it's worth, I messed around with a similar transmitter/receiver like this for fun, and found that using a stable voltage on the transmitter and receiver helped with frequency drift. I ended up using a Any Volt Micro on the transmitter, and a 12V NiCd pack on the receiver. I also made a Goof Proof patch scaled to it's frequency, and that was a huge improvement. It was all good fun, but barely worked at best... It was still good fun bombing around the back yard though, not really worried about crashing the plane or the video gear. I still have that stuff, maybe I should dig it out and throw it on a Pico Stick or something! lol
  13. How much will it cost me for indefinite calm days?
  14. Just a little more info... In preparing for a flight this evening, I just tested the Lawmate gear with my Easy Cap. It sees the video and captures just fine. I'm not sure what the deal is with my Mini-DV camera, but it still refuses to see any signal at all coming from the Lawmate transmitter. Guess I'll be using my laptop while I wait on a scope to investigate further...
  15. Definitely looks like multipath to me. It's not uncommon to see it indoors where the signal is free to bounce off of may reflective structures in the building.