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garris2

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About garris2

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    RC-Cam'er
  1. So I had a close look at the cct board again. I removed the channel select button to reveal more clearly whats going on. I can see from the mic the trace goes to some audio amp circuitry then through to a hole taking to the other side of the board.On the RF side a simple trace takes the audio over to a solder pad for audio input to the RF module. I've cut the trace isolating the mic circuitry. I also wanted to make a clean hack for the audio input. So I found that I could remove a resistor between the 5v output connector pin and regulator circuitry isolating the pin. Now the 5v output becomes the audio input and a wire run internally directly to the RF module audio input completes the hack. I've verified the vtx accepts extremal audio now and transmits by rigging up camera and mic on the bench and receiving loud and clear without distortion at my goggles. Thanks very much for your help on this Thomas, it's very greatly appreciated.
  2. He's some pics of the RF board. I hope the quality is sufficient to get some useful info. If not let me know and I will take some more. I will do some probing and report back.
  3. Hi Thomas, Feeding the Rf module directly would be my preferred method, thus far I couldn't identify the audio input solder point but I will look at that again. I assume if I correctly identify it I can simply cut the track close to the module to isolate the other Mic circuitry. In case, I will buy some other smd resistors and play around with values as suggested. Thanks
  4. Hi Thomas, thanks for your reply. Its very helpful as always. A reading of the Eagle Eyes manual indicates the audio output level as "line Level". Reading your link and this one about Line_Level I'm going to build a L-Pad attenuator as follows using 0805 smd reistors and fit it inside the transmitter case. I/P voltage: 2v O/P voltage: ~ 3mV R1 = 100Kohms R2 = 150ohms Will report back. Best Regards Geoff
  5. Hi everyone, I bought this Video_Tx for use in my ground station as a repeater up to my goggles. At the time I didn't realize it doesn't accept external audio but instead has a little mic built in. I want to know if I can remove the mic and wire up my external audio to the solder pads adjacent to where the mic was located? Would I require a resistor (value?) between the audio source and solder pad? The external audio source is just one of the audio outputs of an Eagle Eyes. Any tips or advice greatly appreciated. Geoff
  6. I've decided to go down the PWM to PPM converter route in the meantime as I don't think there is enough interest in the ET OSD community at the moment to warrant Bills time and effort. Geoff
  7. Thanks for your replies guys, the OSD's makers name is Bill (no more clues will be given). I will try to sweet talk him and in the mean time I might try to build the project above. I looked at the FrSky receivers as linked by Kilrah but they are limited to 10 channels and I would like to make full use off my 12 available channels with my existing system. Geoff
  8. Hi all, I'm looking for a Futaba SBus to PPM converter. Does anybody know of such a thing with a proven working track record or would anybody be interested in building such a thing? (Hint to Thomas) I'm sure it would be a great seller. SBus protocol I can't vouch for the accuracy or completeness. http://www.flightronic.com/index.php?page=futaba-s-bus-protokoll There is also this but it is sold as a pcb only and I dont have the knowledge to program it, ( I could build it), I could not find any reports attesting to reliability, some negative actually. http://ddfpv.de/projects/s-bus-to-ppm/ I would like to feed PPM into an OSD that has newly developed firmware to support PPM in while still having ordinary servo connectivity to the receiver for things such as Head Tracking, flaps etc I've considered a PWM to PPM encoder but it would add wiring complexity as I still want access to the receiver outputs for the above mentioned things such as Head Tracking and Flaps etc. If eventually I need to use a PWM to PPM encoder I will stick with my Futaba R6014HS, If I find a proven (or one is built) SBus to PPM converter, I will be using a R6108SB receiver Geoff
  9. New Update. password: 2.4G RC off Here is a sort clip where I turn off my 2.4G RC Tx to compare what my video is like when RC is On/Off. At about 49sec into the video I turn off my RC Tx (after RTH has manually been engaged) and I think there is a slight improvement in video quality. At the 1:26 mark I turn 2.4G RC on again and a barely perceptible decrease in video quality can be seen. And then again at 1:43 I turn RC off and on again at 1:53 Conclusion: I think its ok in my case to have the 2.4G RC Tx Yagi positioned so close to the 1.2G VRx yagi. Geoff Edit: Well I just watched the video after I uploaded it to vimeo and if anybody can tell the difference in quality in that video, I go he. Recorded quality is much better, I just don't know how to make it look good for upload, sorry.
  10. Update: Ok, I have tested as suggested following the proceedure in Post #4. I applied my DMM to the RSSI output of the Lawmate receiver with all transmitters turned off. The reading was 124.4mV. This reading was a bit low I thought, so I verified by turning the video Tx on and the RSSI went to 3.78v I turned the video Tx off again, RSSI went to 124.4mV and then I turned on my RC Tx and WiFi Amp. Both LEDs on the Amp illuminated indicating power and signal were applied and received. I noted the RSSI voltage of the Lawmate VRx and it was still solidly at 124.4mV i.e. there was no observed change in the RSSI level with my 2.4G 2W Booster Amp feeding my 7dBi yagi placed at 3" separation from my 1.2G Video yagi antenna. I've so far only made this test on my channel frequency of 1.280GHz. I went flying on the weekend and had another good flight out to 6Km. I know this is not stunning range but I can report that video quality is better than my previous flight. The reason is that my friend has changed his video goggles repeater frequency away from mine which has improved picture quality for both of us. I forgot to perform an RC Tx power off test that I said I would do probabily because I was having too much fun and things were working well. I will try to do that test next flight. Geoff
  11. Thanks guys, I'm setting up with an OMM dual Notch filter at the moment too on my video Tx. Geoff
  12. Thankyou again for your replys Mr RC-Cam and Terry. I will give those tests a try as soon as I can. I actually have one of those DPCAV RSSI display meter kits connected onto the Rx already, would it be helpful in performing some testing? In addition to the testing above I guess I could power everything up, note the RSSI level and then turn off the RC control Tx and note the reading again. Actually thats probably not all that dissimilar to what you have suggested Terry. Yes I do have a RTH system set up and working well. On a side note, I turned off my other RC Tx (JR) once, mid air, and it didn't end well. But I feel much more confident attempting that with my Futaba. I will do that as well and see the result. I agree that 2W may be high but I went ahead with it because I thought 2.4G would be attenuated quite sharply at long distance, I think thats correct isn't it? Anyway, thankyou both for your guidance. Geoff
  13. Hi Terry, thanks for your reply. I have tried it, 1 flight so far and it seemed to work fine. RC control was no problems although video was not as good as previously but that could also be due to the fact there were 3 of us FPVing at the same time all on the 1.2/1.3G band on different channels. I'm wondering what general radio knowledge others have in relation to close proximity of Tx and Rx antennas. Why do I want 2W of power into a 7dBi aerial. Well they don't make .5W boosters so you go with what you can get. The 7dBi yagi was on hand too, and of a reasonably compact size so I thought it a good stating point. I tried the 1W booster and it worked well, the boosters are a really good solution for those that want to fly long distance and use more than 8 channels (me 12). All but one of the long range UHF systems only support 8 channels and the one long range system that does support 12 channels only does so for the Multiplex EVO12 which you can't do head tracking easily. Using a booster with my Futaba 12FG allows me to fully use all 12 channels and have a really good head tracking setup. When I was feeding the booster into an omni I was getting occasional Failsafes at 7km so I am trying to improve on that. For some people its about flying low around the local oval, for others its about pushing the boundries of possibility, I like to do both. Imagine if nobody had ever put a camera on their model aeroplane in the first place (why would anybody want to do that?), none of us would be doing any of this. cheers Geoff
  14. Hi all, I have a 1.2G 12dBi Yagi mounted on my antenna tracker and I recently added a 2.4G 7dBi next to it, about 3 inches seperation. I can't seperate the antennas any further whilst still having them on the same antenna tracker. The 1.2G is for my video reception and the 2.4G is for my RC Tx to aeroplane. The 1.2G is feeding into a standard Lawmate Rx channel freq 1280 (http://www.nghobbies.com/cart/index.php?main_page=product_info&cPath=1_5_93&products_id=179) and my 2.4G is being feed by this booster (http://cgi.ebay.com.au/Powerful-2W-33-DBm-WiFi-802-11b-g-Booster-Amplifier-/250785163369?pt=AU_Computers_Networking_Accessories&hash=item3a63f5e869). The Booster is feed from my RC Control Tx Futaba FASST 12FG TM-14 module moded with an SMA connector output. My question is, is it bad to have the antennas mounted so close together (detrimental affects on the 1.2G system)? I recently purchased this device 2.4G High pass filter (http://www.dpcav.com/xcart/product.php?productid=16439&cat=267&page=1) with the idea of placing it in the feed line after the booster to the 2.4G yagi. Would it be helpful in this situation? In reference to its position in the feed line from the Booster to the 2.4G yagi, should it be placed at the output of the Booster or the input of the antenna? thanks v much Geoff
  15. I guess I don't get any prize for guessing but I don't think they have a 1.2G 1W tx, but they do give great service. I guess you can't have everything. Geoff
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