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About bluegill

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  1. I was wondering when somebody would do this. Why did you find it desireable to sense two of the leads, instead of only one? --bluegill
  2. I get no video, like when the transmitter is off. At home, where I can have the transmitter and receiver only 15 feet apart, I get a snowy picture. At much greater distances the receiver's squelch operates and I don't get anything. When I bought the video system I mounted the camera and tx on a rc car and my 9 year-old friend and I had a blast driving it in and around the house, so I am familiar with the deadspots in the house due to large metal objects like stoves, refrigerators, and furnaces. I now get not much of anything at all, not like I had up until a couple of weeks ago. There haven't been any crashes or other traumatic events.... --bluegill
  3. Hi Kilrah, thank you for posting the frequencies -- it'a a big help! I recently have run into a problem where I lose video after about 5 minutes, and I haven't been able to figure out if it is the transmitter, the receiver, or what. Having only one of each makes it hard to troubleshoot! So I am planning on buying another tx/rx pair from BW, because that is what I already have, and your frequency list shows there are no alternatives if I want to be able to mix and match. The frustrating thing is that this problem has cropped up but I haven't made any changes to the system. I did take the transmitter to a ham friend who has a power meter that can measure power at 2.4GHz, and the tx put out continuous power for 25 minutes -- far longer than I've been able to run without something cutting out. And yes, I ran it from the same power source (battery and voltage regulator) as when I fly. The only change I made was to take off the antenna and connect up the power meter. Oh yes, the other difference is the transmitter and voltage regulator got much hotter than usual because the plane was on the bench instead of flying. Oops, I forgot one more thing -- on the bench I didn't hook up the camera so there was no video signal going to the transmitter. I didn't think that would make a difference. So that seems to leave the antennas, the receiver, and the video cables from the receiver to the display as being the likely suspects. Has anybody else run into a similar situation? --bluegill
  4. You just think it's a joke! I'm already looking at the connector for the external switch and LED with the idea of watching those flashes in my telemetry stream. Just think of the heartthrob it would make if it were connected to the roll indicator of the MAHI... --bluegill
  5. Being the cheapskate that I am, does anyone discount the price of the FMAdirect FS5 receiver? --bluegill
  6. Sometimes I think I'm slow, real slow. I was going to whine yet again that this technology is wonderful, but there is no immediate feedback to the pilot. After reading FMAdirect's manual for how to use this receiver with a copilot I finally understood -- just set the failsafe of a high channel that you don't use for flying the plane to indicate a problem! Duhhh! So in my case I could set the receiver's failsafe for channel 5 go to +100, while for normal flying it would be 0. Connect that channel to the MAHI pitch indicator and I can immediately see when the receiver goes into failsafe mode. If I had my druthers I would like the receiver to also have an output that indicates glitches as they are received (it only goes into failsafe after not getting a good signal for about a second), but it looks like this receiver addresses my main concerns. Now if only I can figure out how to get the other info from the receiver while the plane is still in the air... Thank you TI for repeatedly presenting your argument until I finally got it. --bluegill
  7. Yes, I noticed that. I also noticed that he claimed he was averaging the current pulse (if it seemed OK) with the previous good one, but what he is actually doing is exponentially filtering each pulse. Nothing inherently wrong with that as long as everyone understands what is going on. Still, it looks like a solid design to start from, and will allow me to get my toes wet in PIC assembler with a useful starting point. I've done a lot of assembler code in years past, but this will be the first time for the PIC, which looks like a *very* different beast than what I'm familiar with. --bluegill
  8. Actually, the mating connector can be simpler than that, because the card needs to get the power and ground pins only once, not for each servo connection on the receiver. So one needs only 7 connections for a 5-channel receiver (power, ground, and the 5 channels). A story in frustration, though -- I designed such a board to make it easier for me to move my Hitec 555 receivers among several planes. It worked fine -- BUT One of my 555 receivers suddenly decided it was intermittantly dead. I looked at having Hitec repair it, but that was nearly the same cost as getting a Hitec Electron 6 that was on sale at Hobby-People. Naturally I bought the new Electron 6. Naturally the Electron 6 not only runs the channels in the opposite order as compared to the 555, but spaces the servo connectors closer together. Do I say ARRRRGH now? --bluegill
  9. Oh yes, I quite agree! That is why I am especially appreciative of the link you gave to Bruce Abbot's project at http://homepages.paradise.net.nz/bhabbott/decoder.html His 6-channel design looks like a good starting point. --bluegill
  10. I didn't mean to imply that the RCFS-V2 is ineffective. In fact, based on your other designs as well as comments about how it works, I would be very surprised if it was not effective. My line of thought isn't about the effectiveness of its glitch-busting, but about informing the pilot that he is getting into dangerous territory and needs to get out. I can tell from your comments about RSSI that your environment is quite different and much quieter than mine. I can easily show areas where RSSI of my receiver shows a strong signal, and that's without my transmitter being turned on! We have a major electric substation near where I fly, and very high tension lines feeding it, and a only somewhat lower voltage line running from it for several miles to another smaller substation. Being on the coast we get salty dew and fog, which means there is often some insulator arcing and creating broadband noise. Which insulator(s) arc varies, and sometimes the electrical noise at the flying field is very low, but other times there are distinct "rays" of noise, created by the lay of the land, buildings, and whatever between the arcing insulator and the field. The position of these rays varies depending on which insulators are arcing. We know of some consistent problem areas, but others show up sporadically and unexpectedly. --bluegill
  11. Yes, I had seen that thread but I thought you had decided not to add it to your list of current projects -- in other words, the preprogrammed PIC chips are no longer available. I certainly do agree with you that I had not seen Bruce Abbot's thread, and appreciate the link you provided. --bluegill
  12. Mr.RC-Cam, you know I like your work and products, but... I think that the whole receiver glitch issue needs to be looked at from a systems point of view, not from the servo's point of view. The RC Servo Failsafe with Glitch Filtering is a great little device, but it doesn't share its conclusions with anyone or anything beyond the servo it is connected to. The only indication one gets (while flying) that reception is spotty is that the plane no longer responds to the controls. I often am not doing anything at the controls for many seconds, so the fact that I am flying into an area with interference, or out of the range of my RC transmitter, does not become immediately obvious. I bought your MAHI (a very cute little device) primarily to make my video transmissions legal (it displays my ham call sign, and I am using way too much power for Part 15). I have been noodling with how to best get glitch info back to me, the pilot, in near real time so I can extricate myself (or at least the plane) before I lose contact and get to watch it fly away. I've been horsing around with the buddy-box connector of my Hitec Flash 5X with the idea that I take the PPM stream from the transmitter and append to it another 3 channels, which are in reality just the first three channels again. On my plane they are rudder, elevator, and throttle, the three most important items for controlling the plane (it's a polyhedral and has no ailerons). In the plane, the idea is to add a PIC chip to the receiver which will compare channel 1 with 6, 2 with 7, and 3 with 8, and if they are not in close agreement then to throw away the info as being bad, and to also put a pulse of current into a capacitor which feeds the pitch input of the MAHI. If I get a lot of glitches in a short period of time the pitch indicator will rise quickly to the stop telling me to get out of there, and when I get back into good reception the capacitor's voltage will bleed off and the pitch indicator will show the reception is good again. RSSI doesn't do much for me for the following reasons: 1. It shows the strength of the signal coming in, but doesn't indicate whether that signal is from me or is interference, and 2. It decreases slowly with distance, while the glitches start popping up in profusion with location the plane is flying in, what other transmitters are in the area, and how much the high-tension insulators on the power lines are arcing due to dew and dust. In other words, there is no "safe" value of RSSI because that depends on the environment, which changes sometimes over a period of several minutes. I've looked at the Berg and other glitch-catching receivers, but I really want to know about problems as they occur, not after the flight is over. One reason, of course, is that I may not see the plane again. But even if I do successfully get the plane back (which I have so far), looking at the LED and seeing that I got some glitches doesn't tell me very much about where I got them and how rapidly or slowly they added up over the course of a 50-minute flight. I've found Francis Thobois' site Radio Modelisme interesting, but I don't think he really addressed the whole issue either. My understanding is that in the US it is illegal to use two channels simultaneously. His other main concept, putting a transmitter ID in the pulse stream is useful, but we still need to get the information back to the pilot as the glitches are being encountered. What are your thoughts? --bluegill
  13. I hope my experience and solution will help someone else who encounters RFI/EMI problems. --bluegill
  14. yb2normal, my understanding is that the error is slowly varying with distance and time, so the plane won't be dancing up and down. However, I wanted people's real-world experiences with WAAS, not the FAA's glowing poopsheet, which is the reason I posted the question in the first place. I guess I'll have to just try it and find out! BTW, I've been considering using a pressure sensor anyway in order to determine airspeed, so I can account for wind. I would really like to know BEFORE I get into trouble that I'm flying downwind in a gale and won't have enough energy left to get back home if I don't turn around pretty quick! --bluegill
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