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Everything posted by Lupy

  1. Ah well, thanks for the replys, I am looking at replacing it with this: http://www.fpvhobby.com/transmitter/12-2-55-volt-500mw-24ghz-video-transmitter.html Which seems to have the same frequency set as my older BW diversity rx, or possibly this : http://www.fpvhobby.com/30-4ghz-500mw-transmitter.html Which seems to be the same unit, but with a mic and power board built in, but would only work on ch 3. I find it odd that the same unit would be sold with 2 different frequency sets, but I supose since there are no crystals, it's all up to the programing. Anyone have a difinitive answer as to in audio will work with these?? they seem to have audio carriers at 6 and 6.5hz for stereo, but I can't find a spec on the lawmate RX, I am mostly looking at these units because of this artical: http://forum.tsebi.com/viewtopic.php?f=4&t=100 Which states that the output dosn't sag with heat unlike the lawmate, and they are capable of 1w (30 db) which would be nice.
  2. maybe it overheated, I had it sitting on for a while with no airflow, do these need lots of external cooling?
  3. Trying to figure out why I'm not getting any range on a small BW 500mw 2.4ghz lawmate 5v TX. I tried to guage current draw, and it's almost nill, around 100ma or less. Only run on 5v, Still getting a clear signal when very close, but 20 ft is about the limit. I can't figure out what I did to it, but it also dosn't seem to get warm like it used to. Is it posible to blow the amp end of these without blowing it up all the way?? I asume it's a brick at this point, I know BW dosn't sell these amy more, anyone with a hot tip as to who has the best price?? Thanks Ken
  4. given the cost of a replacement, and the value of the complete plane, I wouldn't trust it in the air. I supose strictly for recording, but given the damage to the board it's a big risk for FPV. Esp given how hot these run, the expansion and contraction could easily break a fix over time.
  5. haven't been keeping up with this thread, but yes use that address, I got the BB back fine a while back. Not really inderstanding the chip you are using, this might not work, but could you have the oracle take a sample of the current video quality, and then do a switch baised on a decrease from that level? The user could select from a set of allowable decreases in quality. This problem with the BB video out levels might also explain why the mobicom 900mhz video tx I had been playing with didn't work if the video went through the BB first.
  6. ah, I never actually flew it, just tested it in the yard and such. I didn't look at it closely enough to see the color/cantrast change. Did you notice that the switching seemed to start off fairly normal, then increase untill it's almost constant? Thanks for taking a look. Ken
  7. my black box is off to you. I agree that it's sort of a dead product, but was hoping to use it untill I made the jump into another OSD. $$$. I figure that it might be usefull to know what is wrong with it, so that the problem dosn't reapear later in a new osd design. It's esp odd, since the video looks fine on the screen. Ken
  8. I supose I could send the Black box to you, I'm not going to use it any time soon. Would like it back at some point of course. Ken
  9. An oracle update: I have been building a twinstar seaplane FPV. I was hoping to use a new mobicom900mhz 1.2watt tx, but it has been shelved due to rf interferance and servo jitters. I have aready reported on another thread that my black box osd did not work with th mobicom tx, even though it seemed to work fine with the airwave modules. I proceded with airwave and the black box, but now I have found that the black box has a problem with the oracle. On first power up, everything works fine, but after 30sec or so, the oracle starts switching, this increases ultill the switching is almost constant. I have tried powering the tx/camera on separate lines, and even separate power from the OSD, thinking maybe it was heat buildup, no luck. I have tried adding extra caps on the video lines, still no help. The odd part, is that I can not see any problems in the recieved image, the data and picture are sharp and clean. rapid switching occours even in the lowest sensitivity setting Any ideas? I can't fault the oracle, as it works fine as soon as the black box is removed. Ken
  10. I wasn't expecting so much noise from this tx. I may just bail and step over to a 500mw 900mhz tx, or look into the future hobbies 700mw one. Using a std shielded video and power line dons't help much, as the ground seems to broadcast noise too. I tried various caps from ground to power, and small filter caps across the servos, without much imporvement. I have had some sucess moving the tx to the rear and running a three conductor (video, power, ground) with a shield not attached to anything. I wrapped the camera in foil, but did not connect the foil to ground or the shield. I don't like this location much though, as the heat sink, tx and battery make a pretty big package with lots of drag. I am running a pan tilt head with 180 deg servos, which seem really sensitive to whatever the 900mhz tx is putting out. I am using a pcm futaba. still getting about 60-70% range.
  11. Is your 900mhz tx by any chance a ebay purchased mobicom tx? I am currently chasing interferance from one using a std pcm radio. I have moved the tx and it's battery back to the tail, thinking it would be cleaner there, the camera is in the nose, with a video only feed traveling through the center of the plane. I am still getting jitter, and only about 60% of normal rc range.
  12. I am trying to tame some interferance I am getting from my mobicom 900mhz tx. I am moving the tx towards the tail, but want to add some ferite rings too. There will be a sielded video/power line back to the tx, camera and battery in the front. I have braided the servo lines, and have some ferite rings, but am a little uncertian where to put them. Servos, close to the rx or the servo? Power cables? Video/power cable? Which end, tx or camera and battery? I was getting some jittering when the 900mhz tx was near the servo lines. When I connect the tx directly to the motor battery, everything jitters and the rx (pcm) drops out. I think I will just use a separate battery. Thanks! Ken
  13. the specs I have seen claim that the loss at 2.4ghz is greater for the connector than for a lot of cables, esp for a couple of feet of resonable cable. Unless you are going to solder a sma plug directly to the back of the antenna, I would think the risk of messing up the cable, would be greater than the gain, esp if the insulation isn't teflon. It can melt and change the spacing. YMMV Ken
  14. it's pretty odd, I broke the video out line, so I could touch inputs for the camcorder or the 900mhz tx in real time, it's there for the camcorder even when the tx is still powered up, so I don't think it's swamping anything with RF. Now I realise that I should have hooked up both the camcorder and tx to the signal at the same time, to see if the picture drops out on the camcorder because of some drain the tx is placing on it, or if the tx is just more sensitive to having a nice video signal, and something about the osd combining the orig video with it's overlay is messing things up. Something to waste more time with tomorrow...... Ken
  15. by terminate, I asume you mean to put a 330ohm resistor from the video in signal (from the camera) to ground. This didn't seem to have any effect. I did discover that if I turn the video to disable, the data screen goes through the 900mhx tx just fine. I know that in normal operation, camera and Black box connected directly to a camcorder, video enabled, if then the camera is unplugged, the whole display dies. So for some reason, the adition of hte 900mhz tx is making the Black box think that the camera isn't plugged in. No real Idea on where to go from here, pretty strange. Ken
  16. I also posted this question on RCgroups, but I know that there are more tech people here. I recently bought a mobicom 900mhz tx 1.2watt. I also got a couple of the rx's to use with the oracle. Ground tests show much more ( over 2X ) range than the airwave 500mw tx. This was with dipoles on 900mhz vs ground plane and patch antennas on the 2.4ghz. I am currently trying to get them in the air. My problem is trying to integrate a black box osd. I have tested the OSD on the airwave tx, and it works fine. The Mobicom TX works fine with the camera and mic alone. When the OSD is inserted into the mix, the picture is lost, audio isn't affected. The carrier signal seems to still be there. Ocasionally, I will get a second or two of video, then it is gone. I have tried adding another cap on the video signal, no change, I have tried putting a video amp/ splitter on it, no change, I have tried moving the osd a couple of feet away, thinking maybe the 900mhz tx is swamping something, no change, separate power lines, etc. At this point, I am moving ahead without a osd, but would really like to figure out what is going on. I would like to use an osd, but want to know if another osd might work, before spending the $$ on it. Thanks for any help Ken
  17. I don't quite understand why you are trying to do what I think you are trying to do. The digital frequency controll boards from Mobicom are designed to be used on their RX boards. The Mobicom rx board already allows tuning of almost any frequency in the band using dip switches. A digital controller board selecting the frequency makes me nervous. If a stray signal or power spike causes the rx to jump frequency, a plane could be lost. Having dip switches seems much safer. I tend to pic a frequency and then leave it alone. Adapting one of these controllers to the lawmate rx seems like overworking the problem since mobicom and lawmate both use the same comtech cans, at least in 2.4ghz and therefore should have similar sensitivity. The lawmate RX is smaller, but one you add the controller, the size isn't as much of an issue. As far as mobicom, I have bought from him, and everything showed up in a resonable time. Best of luck. Ken
  18. I have a set of cy-visor goggles, with the stock default settings, I get a lot of flicker, if I go through all the menues, there is a flicker setting which removes the effect. There is an adjustment for left and right sides. Not sure why, but the stock settings are pretty bad, color is off too. Once I did some adjusting, they look much better.
  19. I like the way the prop still turns over a couple of times from the wind Nice clear reception, only one dropout near the end.
  20. Got done doing some field testing with the 1.4 firmware. I believe I have an exceptionally noisy environment flying over a lake with a seaplane. The 1.4 firmware was much better at picking a rx and sticking with it over the 1.3 version. I was using the default sensitivity, and was getting lots of switching, but it no longer wanted to stick with the lower input. I didn't see any evidence of breakup during switching. Thanks again for making such a usefull product. I no longer get random dropouts like I used to, and it has made me much more confident in the stability of my vid link. Now to get my twinstar built with a pan tilt mount. Ken
  21. just an update, I was having some problems with the chan one bias, I tried several other settings, and it still seemed to be there, so I am excited to hear about the new version. I think it's presently good for a std diversity setup, with both antennas pointed in the sme area, but for an overhead pass, where one antenna is pointed one way and one the other, then it really needs to switch and stick. I'm not sure why mine seems to have more problem with this than most others seem to be having. I think it might be my flying off water, there may be more multipath, or the signal may be getting degraded quicker. Thanks again Ken
  22. Just got back from flying the version 1.3 chip. I was not flying under the hood, so it was a little hard to see exactly what was going on. I haven't had a chance to review the tape yet. I flew with the factory settings which were a level 3 sensitivity. For the most part, the switching seemed pretty clean, with no breakup visible on the lcd screen. I did notice that it wants to stay with the left or lower video input. I positioned the antennas towards the left and right, and when I flew to the left, it was pretty quiet, with just a couple of chirps. When I went to the right, the chirps were almost constant, and some noise was getting through. I thought it was my antenna or rx, so I reversed the inputs, and the situation was the same, the lower input was the prefered one, even when hooked up to the other rx. so the rx's and antennas were not the cause. I will try flying with different sensitivities, and see if the situation changes. interestingly, I was unable to duplicate the situation on the bench. I think that when the signal is mostly clear, then it switches and stays there, but when there are a few errors all the time, then it wants to stay with the lower input. It's almost like it's more tolerant of errors on the lower input. When I made the back layout, I was orig going to use vid input A and B, but then that would have required a mark on the front as to which light was A and which was B. Usually, the antennas will be placed with one on the left, and one on the right. As long as everything is setup properly, it's easy to see by the lights if one antenna isn't getting much use, and adjust it. If the back is labled A and B, it's easy to make a mistake with the tangel of wires and have the left light indicating the rx on the right. Also, If you use A and B, then if the left light is A, to read from left to right A-B, then the back will be labled with B on top and A underneath. Now I'm totally confused. ;-) Of course it's really a mater of personal prefrence and what is easy for setup. I also got a surprise in the mail today, my long lost 1.2 chip arrived. Here is a pic of the package. It looks like it stuck on a roller and a lot of the lable was removed. It must have been there for quite some time, as it's been in transit for ~2 weeks. Mr RCcam, do you think it's worth it to try the old chip to see if it has the same prefrence for the lower input? Ken
  23. I should have mine back up and running this weekend. I plan on running the rx sound output into the "left" for one RX and the "right" for the other. That way, with recorded video, the sound should switch back and forth to indicate which RX is active. I too found it interesting that the two diversity systems rarely broke up at the same time. It makes me think again that having a 4way would be better, but a lot more $$.
  24. wow, that's pretty cool. Right up to the end, I think the Oracle had the edge. There were a number of instances where the RSST version had breakup that wasn't present with the oracle. There certianly didn't apear to be a huge advantage of one over the other. What rx's did you use? Was your RSST system a BW version or something else? The ultimate test would be to use only two rx's, and split the video feeds so that each diversity unit had the same input. Then both will see the same interferance at the same time. Not sure how hard that would be to do with a BW unit, since it's all in one box. Ken
  25. Thomas, your caps are a lower farad rating than called for in the specs, do you find that there is any neg effect? Also, Isn't this a 4ch rx? is the 4th ch selected when none of the chanel switches are selected? Thanks Ken
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