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drigotti
07-01-2017, 04:38 AM
My Hummel 1915cc engine with a Slick 4220 mag makes my hand held radio reception awful! Best I can tell there is NO RF suppression in the ignition system at all.

The electronic secondary hardly allows any static. So my focus is on the mag side of things.
I have the P lead from the mag in a shielded cable. The shielding is attached at the mag end. The P lead goes to a panel mounted toggle switch. The switch then closes to a nearby ground to stop the engine.

Has anyone used low resistance suppression wires with this mag to reduce the RF noise? The wire I'm looking at measures at 201 Ohms per foot. What spark plugs do you use? Any real world experience feedback would be GREAT!

Thanks!

Dave

Dana
07-01-2017, 08:18 AM
The 4220 mag was designed to use with shielded wires and plugs. Resistor plugs help, as do the Great Plains spark plug covers (the covers require a shielded harness). See also the magneto article I wrote for Kitplanes magazine. (http://www.homebuiltairplanes.com/forums/showthread.php?t=26009&highlight=)

drigotti
07-01-2017, 09:14 AM
Thanks Dana,
BUT.....I'm looking for feedback on anyone using suppression wires not shielded ones with a mag.

Dave

1600vw
07-01-2017, 09:48 AM
I use solid core suppression wires on my 1/2 vw it has a FB mag. I have no issues at all with noise in my radio. My antenna is mounted aft in my fuselage or behind the cockpit. I had a local man who makes spark plug wires for the racing folks make me up these wires. He used some huge wires for this. Nothing like what you would find in an auto parts store but more like what you would find at a good hot rod shop. Again these are solid core. i would not use carbon wires in the air. IMHO.

Tony