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  • #31
    That was my thought on Saturday when Mark told me results of the changed radio and making sure the 25k micro Farad 50 Volt capacitor is definitely in line before the consumer from the charging circuit. I highly suspect that the antenna cable has been pulled/tugged and has lost some connection since the first radio did not have issues except the dual volume software feature was not on it. We use a dipole Sirio MD-133 VHF antenna which has a built-in cable of a certain length and end connectors. Its already tuned for VHF range used in aircraft right from the factory. That is why they advise not to cut and change the length of the cable. Highly unlikely this is an actual wiring or radio issue at this point. That would be very surprising to me. Will be sending Mark a new antenna to change out to. Taking the tail off sounds like a lot but in fact should not take more than 0.5 hours of labor to do.

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    • #32
      ( I highly suspect that the antenna cable has been pulled/tugged and has lost some connection since the first radio did not have issues except the dual volume software feature was not on it.)...
      The cable was never stressed or pulled in any way by me. There is plenty of slack behind the panel to leave it attached while pulling out the panel. However, I've always disconnected it from underneath before ever turning the first screw.
      My thought, like yours, was that perhaps something happened to the cable when it was originally threaded through the keel. I believe the antenna and cable should be replaced as a unit as well.
      By the way, is the rear antenna connection a standard BNC type as is the front? It does not appear that way in the website diagram.
      I need to add here (for the readers) that Silverlight has been continuously supportive in this effort. Thanks to Abid & Co.
      Testing and further updates to follow....
      Mark
      __________________

      Risk lurks in the edges of marginality.. ..There are penalties to be paid for pushing the envelope..
      The speed in which a woman says "nothing" when asked "What's wrong?" is inversely proportional to the severity of the storm that's coming.
      No tyrant, foreign or domestic, should be permitted to die a natural death.

      Comment


      • #33
        I really can feel ya! I have fought intercom and radio issues for 5 years. I have tried Comtronics intercoms, Sigtronics intercoms, and one with no name; to no avail. The communication between my passenger and I was horrible at best. I purchased an Xcom 760 with built in intercom, and tried it. Numerous issues with it also. I even sent it to Austrailia twice for repairs. It now has residence on a bench in the hanger.
        Everyone that I spoke with always spoke the most highly about the Flycom system. So, I ordered 2 helmets and an intercom and patchcord and PTT cord through Silverlight with Abid, and installed it on my Dominator. On Saturday at Mentone this year, I gave John Roundtree a ride. That was the first time for me to use the intercom and Icom A6 radio. The communication between us was incredible, very clear, no buzzing or whining or wind noise.
        Yesterday, I give 2 rides at my local airport; to two different individuals that have never flown. They both told me that they could hear me perfectly and there was not any outside noise.
        All I can say is, I HAVE NO REGRETS BUYING A FLYCOM SYSTEM!!!
        I see you already have the helmets, buy one of the intercoms and patchcord and get rid of all the frustrations. I did.
        It also give the ability to transfer it into my Kolb easily also.
        David McCutchen
        615-390-2228
        Bensen B7m, 90 hp Mac
        Dominator Tandem, 100 hp Hirth
        Kolb Mark III Classic, 80 hp Verner
        Certified - Advanced Master Beef Producer
        EAA Member #0511805
        PRA Member #28866
        PRA Chapter 16 Member
        Secretary & Treasure - PRA Chapter 16
        President / Sylvia - Yellow Creek Volunteer Fire Dept.
        Chairmen - Dickson County Veteran's Day Committee
        Volunteer - Dickson County Airport Aviation Day Committee
        2 busy 2 No!

        Comment


        • #34
          Originally posted by Gyro28866 View Post
          I HAVE NO REGRETS BUYING A FLYCOM SYSTEM!!! .
          What David said X2

          My only complaint is that the Flycom helmets are hot for summer, but worth it for the clarity of comms.
          Scott Waggoner

          Comment


          • #35
            Dave & Scott, I really enjoy my Flycom Helmets. They work well for noise attenuation and are very comfortable. Year round, I simply wear a cloth skull cap (doo rag) over my hair and it keeps the inside of the helmet liner dry and cool. Also hygienically beneficial for each passenger as I make them use one.
            If there was one thing Flycom could improve upon, it would be to add a few slide open/closed vent holes. I believe that would help immensely with the summer heat issue.
            The issue here is not one of headgear . It is the MGL V6 radio. It has a built in intercom that works well once properly programmed for 'dual volume' control of the radio/intercom.
            The problem came when the radio cut out on me in flight a few times in 'heavy pattern traffic'. During that time, the power to the unit remained on and I could see the active/stdby. channels on the screen and also communicate over the intercom. The radio was silent for both reception/transmitting until I 'rebooted it'.
            I rewired according to Rotax specs. only to have the same thing recur. Now I'm waiting for a different antenna to test and if that doesn't work, a replacement voltage regulator/rectifier (although I highly doubt it is an electrical issue at this point).
            FYI, Flycom does not make a compatible patch cord for my model radio. Only for those that do not incorporate an intercom with the radio. More to come after testing. Thanks for all the suggestions.
            Last edited by mark treidel; 08-31-2017, 09:56 AM.
            Mark
            __________________

            Risk lurks in the edges of marginality.. ..There are penalties to be paid for pushing the envelope..
            The speed in which a woman says "nothing" when asked "What's wrong?" is inversely proportional to the severity of the storm that's coming.
            No tyrant, foreign or domestic, should be permitted to die a natural death.

            Comment


            • #36
              Originally posted by mark treidel View Post
              The cable was never stressed or pulled in any way by me. There is plenty of slack behind the panel to leave it attached while pulling out the panel. However, I've always disconnected it from underneath before ever turning the first screw.
              My thought, like yours, was that perhaps something happened to the cable when it was originally threaded through the keel. I believe the antenna and cable should be replaced as a unit as well.
              By the way, is the rear antenna connection a standard BNC type as is the front? It does not appear that way in the website diagram.
              I need to add here (for the readers) that Silverlight has been continuously supportive in this effort. Thanks to Abid & Co.
              Testing and further updates to follow....
              Hi Mark:
              Yes everything points to some intermittent connection in probably the antenna connector or cable IMHO though I could be wrong but I don't believe in too many co-incidences. Process of elimination is pointing this way. The Sirio dipole antenna we use comes with a built-in and tuned cable. Its hard wired on the antenna end (no connector there) and has a screw on BNC connector on only the radio end. If somehow during snaking the cable through the keel tube the built-in cable snug out a tiny bit, there is not much else to do but to change the whole thing carefully.

              I would simply try the new antenna we mailed you first by putting it and securing it to the seat belts with zip ties and letting it sit on the back seat. It does not need a ground plane. If that seems to work, we know the problem

              Comment


              • #37
                Might want to verify there are no intermittent shorts between center conductor of RF cable and shield with ohm meter. This may happen if connectors installed incorrectly or cable cut somehow during routing. Also the 25,000 caps can be bad new. I had to rewire the placement of the 25,000uf cap so it was closer to rectifier since it had 10' of wire between output and cap causing RF interference. This fixed my issue, but also installed a Lonestar power filter for the radio. I didn't end up needing it but installed it since I had already bought it. Lonestar has a mag filter too which I installed for same reason. Power clean now. Check it on oscilloscope if you have one handy.
                Last edited by DavePA11; 09-02-2017, 05:06 AM.

                Comment


                • #38
                  Dave I think Mark's problem may be the antenna,but I also installed the same lone star filters that you did and all of my radio problems went away.

                  They really work as advertised,great products.
                  Best Regards,
                  Eddie Sigman,Polvadera,nm
                  (575) 835-4921

                  Comment


                  • #39
                    Any updates Mark?

                    Comment


                    • #40
                      No Dave....Thought I had it though. Flew w/o a problem for over an hour. Radio was fine after rechecking all connections and then from Base to Final...radio crapped out....Sheesh!!
                      If I didn't have to rewire the whole new loom, I'd have gone to a different brand long ago. I'm ready to put a bullet into it, honestly. Or perhaps a Viking funeral??!!
                      I will keep at it though. I love a good challenge, no matter how challenging.........It makes the reward (or the revenge) that must sweeter!!
                      Last edited by mark treidel; 09-13-2017, 07:00 PM.
                      Mark
                      __________________

                      Risk lurks in the edges of marginality.. ..There are penalties to be paid for pushing the envelope..
                      The speed in which a woman says "nothing" when asked "What's wrong?" is inversely proportional to the severity of the storm that's coming.
                      No tyrant, foreign or domestic, should be permitted to die a natural death.

                      Comment


                      • #41
                        Mark, you should really contact some ham radio geek and ask him to do an SWR measurement on your radio system. This is an easy thing to perform and tells you a lot. You need to check the SWR over the enitre range from 118 to 137 MHz. Doing this requires about 10 minutes, and it is non-destructive. Modern radios will switch off when the SWR gets too bad (usually > 3.0). When measuring the SWR you need to be outside of the hangar, away from any large metal structures. The radio signal needs to be able to radiate away freely.

                        A dumb question off the bat: you *are* using the correct type of coax, right? A 50 Ohm coax cable. I am asking because the most common type is the 75 Ohm coax cable used a lot in cable TV applications. You should be using 50 Ohm RG 400 type coax which has a double shield around the wire braid. And have an experienced person with the right tools do the connection because a faulty connection is virtually impossible to detect visually. Also, keep the coax line as short as possible without coiling or routing around sharp corners. And keep the radio antenna cable far away and not parallel to the transponder cable.

                        There are some other simple tests I would perform. First, verify that you can reproduce the problem on the ground with the engine running. Then feed the radio from an external battery and see if the problem persists. If it goes away it is some power issue (most likely short spikes of too high/too low voltage). If it doesn't, you can forget power related issues.

                        Another test would be to get a 75 Ohm dummy load (any avionics shop has such a thing, it costs a buck to make one yourself) and connect it directly to the radio output, right where the antenna cable goes. Just disconnect the latter and replace it by the dummy load. This 75 Ohm resistor simulates a perfect antenna without any of the potential problems associated with a real antenna. If the problem goes away, you know right away that the fault lies somewhere "downstream" of the radio.

                        With these simple tests you should be able to locate the problem to either the power supply/connection, the radio itself or the antenna cable and antenna.

                        Greetings, -- Chris.

                        -- Chris.
                        Last edited by ckurz7000; 09-14-2017, 04:42 AM.
                        Read about my trip across the USA in an MT03 gyro here.

                        Comment


                        • #42
                          Thanks for the suggestions, Chris.
                          The cable is a 50 ohm. What puzzles me is that the radio goes out on it's own...NOT when I transmit, but just stops receiving. Then, when I notice it (all is too quiet) I try to Xmit and that's gone too.
                          I have yet to replace the antenna cable (had no time lately due to a family loss) but that entails taking the entire tail empennage off, pulling out the old cable which is threaded through the keel tube and reinserting the new one. A major undertaking for me. The other thing is to replace the regulator/rectifier but it tested ok.
                          You say most new radios will turn off when the SWR gets above 3.0. If I understand this correctly, that means you have to be Xmitting. I was not when it crapped out. ???
                          Mark
                          __________________

                          Risk lurks in the edges of marginality.. ..There are penalties to be paid for pushing the envelope..
                          The speed in which a woman says "nothing" when asked "What's wrong?" is inversely proportional to the severity of the storm that's coming.
                          No tyrant, foreign or domestic, should be permitted to die a natural death.

                          Comment


                          • #43
                            You are correct: if the radio cuts out also when you haven't been transmitting then that points to a different problem than SWR or antenna mismatch.

                            That leaves two big areas for the fault to live in: power supply to the radio and the radio itself. You can't do much about the radio itself if it is faulty except for repairing or replacing it. However, it is easy to check out the power supply issue.

                            I would power the radio temporarily from battery without the engine running. Just let it sit and see if it shuts off. If it does, it is clearly not a power issue. Next, power all the other avionics and lights on (particularly the transponder and the strobes are suspicious) and see if that makes it cut out, still with the engine stopped and all powered off a (big) battery. Then turn on the engine on the ground and remove the battery. Now, with everything powered off the alternator, does the fault occur?

                            You might also have a ground loop problem. This is the case when you have two (or more) ground connections on your radio. One might be through the antenna installation and the other one might be through the negative power supply to the radio. These ground loops can cause huge problems and noise on the supply lines, particularly in an electrically "noisy" environment.You need to make sure that everything electrical is grounded just once and preferable all at one central point.

                            -- Chris.
                            Read about my trip across the USA in an MT03 gyro here.

                            Comment


                            • #44
                              Chris, you speak of a dual ground issue. The antenna Silverlight uses (dipole Sirio MD-133 VHF antenna) is used in both trikes & all his gyros. It is mounted inside the vertical stab and grounded
                              via its attachment point to the keel tube wherein the cable is threaded through it to the front of the gyro where it comes up behind the panel to the radio. I have made sure it doesn't interfere with other
                              wiring as best as possible and that it is not kinked or coiled. Connection points are solid. The other ground is of course, the negative power supply. As I understand, this should not affect the setup, correct?? There is no 'noisy' environment as you suggest. All wiring is aircraft specific specs and shielded, etc.
                              I appreciate your troubleshooting suggestions and will continue to 'research' the issue until it either resolves or I set a match to it!!
                              Mark
                              __________________

                              Risk lurks in the edges of marginality.. ..There are penalties to be paid for pushing the envelope..
                              The speed in which a woman says "nothing" when asked "What's wrong?" is inversely proportional to the severity of the storm that's coming.
                              No tyrant, foreign or domestic, should be permitted to die a natural death.

                              Comment


                              • #45
                                A dipole antenna needs no ground plane and no grounding either. Just the coax connection, which goes to a device called a "balun" (probably integrated into the antenna somehow) and then to the antenna itself. That is different from a normal whip antenna which has a direct connection tonthe coax and requires a ground plane. I would have to look at the antenna itself to be sure. But as you say the problem also occurs when you are not transmitting. Does the radio work normally when it happens not to shut itself off? Can you receive and transmit to stations reasonably far away?

                                A rule of thumb: At 5000 ft AGL you should be able to establish 2 way communication with stations approximately 50 miles away.

                                -- Chris.
                                Read about my trip across the USA in an MT03 gyro here.

                                Comment

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