You are right Ira,
The usual culprits though are the amateur wiring mistakes we all make.
Ferrite cores are a band-aid. Remember the problems with the Gen 1 Blue
Mountain, and the horrible comments from the field. When I rewired the
panel and properly shielded the BM inputs and outputs, and made sure the
bundles were clear of the back of the Becker radios, all problems
ceased. Too bad the problems inside the box didn't.
Steve,
Noise is best chased through a slow and meticulous chasing of each
component in the panel.
That is why I have a bench, complete with com and engine sensor testing
leads to insure all my mistakes are made on the bench, not once the
panel is in the plane. (Another reason I make the panels with cannon
plugs is to make install and uninstall quick and easy for just this
reason. It is an airplane, if you don't put it together and take it
apart at least 5 times you're doing it wrong.) That aside, other forms
of noise you don't anticipate can creep up.
Along with what Ira wrote, do watch that the power bundle from the
alternator (if equipped) or Dynamo wiring is not parallel with the
Airmaster Wires. They become antennas that way without proper
shielding. Check alternator on off and every component in the panel.
There is no replacement for good sound troubleshooting and careful
craftsmanship.
Happy Building
Bud Yerly
----- Original Message -----
From: rampil<mailto:ira.rampil@gmail.com>
To: europa-list@matronics.com<mailto:europa-list@matronics.com>
Sent: Wednesday, November 26, 2008 7:36 PM
Subject: Europa-List: Re: Use of Ferrite Cores & RFI
<ira.rampil@gmail.com<mailto:ira.rampil@gmail.com>>
Do you still have RFI when you pull the breaker on the Prop Control?
Do you have noise when the engine is off?
Do you have noise when the prop is changing pitch?
Respectively these circumstances could implicate the control box,
the brush plate, or the pitch motor.
If you really want diagnostic help, then it would be helpful to
provide a useful amount of information.
Bud: Ferrite beads and cores have been tremendously oversold as a
panacea, but for specific applications and circumstances they are
champs.
--------
Ira N224XS
Read this topic online here:
http://forums.matronics.com/viewtopic.php?p=216473#216473<http://forums
.matronics.com/viewtopic.php?p=216473#216473>
http://www.matronics.com/contribution<http://www.matronics.com/contributi
on>
http://www.matronics.com/Navigator?Europa-List<http://www.matronics.com/N
avigator?Europa-List>
|