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Scott asks:

<<-have you added anything to your solenoids, and do you think they really

need anything?>>



On the coil side, definitely. Use a MOV (see other posting)



-if you could add anything, what exactly would you add to them so I could

order them from an electronics shop.>>



See other posting.



<<-did you add anything to your alternator for noise? anything else you fell

is really needed?>>



Controlling noise is best done at the source (You can't fix diarrhea by

fooling with the plumbing in the bathroom). Unfortunately there are no pat

answers to fix noise. Each source has to be addressed individually.



Motors with brushes make a lot of noise so capacitors (to reduce brush arcing)

can help here. A significant portion of alternator noise is generated by the

regulator contacts opening and closing so I would definitely use a linear

regulator (B&C for example). Wire routing and layout is also important. Keep

noisy lines together and away from audio or COM antenna lines. One trick is to

run power and ground to a noisy source as a twisted pair to reduce radiated

noise. This works because a wire carrying a current has a circular magnetic

field around it (like your fingers around a rope) so when it is put next

another wire with the same current but in the opposite direction, the two

magnetic fields cancel each other. Twist the wires using a power drill until

you have about 4 twists per inch and if you reverse the drill a little before

you unchuck (dechuck? upchuck?) the wire it won't tangle on you.



One fellow I know wired his plane with all the power lines down the left side

and all the grounds down the right. VERY BAD IDEA as this forms a giant loop

antenna with all the electronics in the middle. He was (is) plagued by noise

problems and I am afraid he won't be able to fix them unless he rewires the

plane!



Hope this keeps you current.



Brent