Phil Matheson wrote: >>I have type 4 VW gear reduction engine, Dynamo type charging system. I have A200 radio, at low RPM the radio is fine, High RPM cruise, I have heaps of interference . I have the radio suppressor's on the system everywhere, but still it is bad. What can I do to help improve the system please.<<
I have an early GPASC (Kohler) single phase alternator in my Diehl case on the Type 1 in N891JF, and I was almost EXPECTING to have to swap it out with a newer 3-phase and newer regulator to quieten it. But it has been absolutely interference-free in every way, with no suppression band-aids at all. When I bought the plane, it had three different noise suppression devices installed in different places, but the radio was still crippled with interference. I credit the noise-free performance to proper shielding and grounding of the radio, intercom, and headset jacks. That is...all conductors to the headsets are grounded to the same place, the "radio end", which is in turn grounded directly to the ground bus....a flattened piece of quarter inch copper tubing bolted to the bottom of the aluminum panel, with several #6 screws through it functioning as grounds, with stacks of ring terminals screwed through it. I'm running a Compufire ignition and regular suppression plugs...exactly what was on it before I rewired it, with the exception of the radio, which is now also an ICOM A200, as opposed to a home-assembled RST nav/com that came with it. I suppose that could be the difference, so maybe I'm talking apples and oranges above. N56ML has a John Deere dynamo and Kettering/electronic ignition, and with the A200 I can barely pick up a slight whine at low RPM (and little air noise) on the ground, but at speed, it is not noticeable at all. -- Mark Langford ML at N56ML.com http://www.n56ml.com
