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NAV Interference

lr172

Well Known Member
I will be installing an archer VOR antenna in the wingtip and coax will run in a conduit with other wiring. One wing has a servo that will generate PWM output for RAC servo trim. The ohter wing will have Pitot Heat wiring that will draw 10 amps, when on.

My question for the expers: Which environment is less harsh for the nav signal running down the coax?

Larry
 
Makes no difference.

I install the heated pitot on the left wing, the roll servo and nav antenna right wing. Work on the first two airplanes - will do again on the current project.

You should be more concerned with LED Nav/strobe RFI. Pick your products with that in mind.

Carl
 
As Carl said, currently I have my archer NAV in my right wing along with strobe, Landing Light and A/P servo and since I am in phase one, I have been testing all of it and so far no issue at all. I would say that you will need a shielded wire for your LL and strobe. In my last plane I did not have shielded wire for LL and had a bit effect on NAV. Once I changed it, it went to zero issue.
 
I'll chime in with another, similar corroborating piece of anecdotal evidence.

I have Archer NAV antennas in each wingtip. The RG400 associated with the NAV antennas is run in conduit with the wiring for the AeroLEDS Pulsar EXP nav/strobe units as well as a Baja Squadron Pro landing light in each wingtip. Both wings have auxiliary Facet fuel pumps in them and the left wing has a heated pitot, again with all the wires run in the same conduit as the RG400 for the NAV antennas.

Zero interference has been noted on the NAV performance of either the GNS480 (left wingtip antenna) or the SL30 (right wingtip antenna).
 
You should be more concerned with LED Nav/strobe RFI. Pick your products with that in mind.

Carl

Yeah, I considered that, but they are on both sides and required by law, so not really part of the decision. I went with FlyLeds and using shielded wire runs. I haven't heard any negative reports on their setup.

Larry
 
As Carl said, currently I have my archer NAV in my right wing along with strobe, Landing Light and A/P servo and since I am in phase one, I have been testing all of it and so far no issue at all. I would say that you will need a shielded wire for your LL and strobe. In my last plane I did not have shielded wire for LL and had a bit effect on NAV. Once I changed it, it went to zero issue.

What brand of lights on the older plane? On the 6, I have Baja's on both sides, but now that you mention this, I am not sure I have flown an approach with the lights on.
Larry
 
I'll chime in with another, similar corroborating piece of anecdotal evidence.

I have Archer NAV antennas in each wingtip. The RG400 associated with the NAV antennas is run in conduit with the wiring for the AeroLEDS Pulsar EXP nav/strobe units as well as a Baja Squadron Pro landing light in each wingtip. Both wings have auxiliary Facet fuel pumps in them and the left wing has a heated pitot, again with all the wires run in the same conduit as the RG400 for the NAV antennas.

Zero interference has been noted on the NAV performance of either the GNS480 (left wingtip antenna) or the SL30 (right wingtip antenna).

Thanks for the input. Did you run shielded wire for the Baja's?
 
Larry-
I have an archer in the R wingtip on the -10, and garmin roll servo out there.
Baja pro lights in both tips, and FlyLED nav / strobes in both tips. Also have facet aux pumps as well
Baja wires are unshielded.
No issues at all.
 
Thanks for the input. Did you run shielded wire for the Baja's?
Yes, Mil-C-27500 twisted shielded 18AWG pair. Shield and power ground wire terminated at my common ground point (forest of tabs).

I also wig-wag these lights using the solid state wig-wag unit from Perihelion Designs. Baja tech support confirmed the lights would respond well to this type of switching and their recommendation is, so far, right on the money.

Absolutely ZERO audible noise from the Baja Squadron Pro lights in either steady or wig-wag operation.

Then again, I'm a bit of a fanatic when it comes to grounding things properly. I have no noise anywhere that I can detect. Spending a few extra minutes to plan and execute good grounding pays huge dividends in the long run.
 
Larry-
I have an archer in the R wingtip on the -10, and garmin roll servo out there.
Baja pro lights in both tips, and FlyLED nav / strobes in both tips. Also have facet aux pumps as well
Baja wires are unshielded.
No issues at all.

Thanks Tom!
 
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