by sport65 » Fri Jan 11, 2019 11:47 pm
I have checked the headset jacks several times to see that the insulating washers were seated correctly.
Which reminds me, My Aux audio jack(music) did not come with insulator washers, so I thought it did not need them, but it does. So I made insulator washers for it (cant buy them for that size). might be the cause of some of the noise some people are getting on theirs. Did not help my problem though.
I don't fully understand ground loops, but I was thinking the ground loop was not associated with power. But rather the wiring of the components (PTT, ADSB, Transponder, etc..) and the shielding to the frame, which stayed the same when I used an external battery ( the radio wiring is still shielded to the frame). In other words, It would have still ground looped on the external battery with the engine running was my thought.
1) It takes a little bit to lock up most of the time, 5-60sec of TX and RX. But sometimes it has been immediate.
2) It did, but only to about 1100rpm, my alternator starts charging pretty low. but the ferrite beads I believe got rid of the rpm effect. its a time issue I believe now.
3) Yes, works fine on battery TX and RX.
4) TX and RX levels are normal, nothing pegged
5) All harnesses are MGL except for extender because they did not sell a harness for it when I wired it up, I only had to do some connections.
I'm not flying it when this happens, it happened at two different airports.
I have to start trying something, so I'm going to try a eliminator filter that is suppose to "clean" the DC power since the ferrite beads seem to work some. It should clean noise from the alternator AND ignition to the radio since I've been told they both can be problems on a Jabiru, and those are the only things that change when the engine is running (I think). If that does not do it, then I'll try resistor spark plugs.
Thanks for all the feedback!
I will update in a bit.
Jeff
Sonex 1570, standard gear, matco independant brakes and wheels, aileron trim, MGL iefis, V6 radio, Uavionix adsb, stx-165 transponder, Jabiru 3300
Finished
Ponder Tx