Hi Pete,

Rule of thumb is never put noisy wiring (motors, transmitters, ignition)
with sensitive wiring (intercom, data, low voltage stuff etc). 

Comms and Transponder are very noisy when they transmit and will interfere
with the position signals of the trim system and may even interfere with the
operation. On a similar note elevator trim motor wiring (and flap motors,
fuel pumps etc) tend to be a bit noisy so don't run them with your intercom
wiring.

If you have to run them together shield the elevator trim wiring (they
usually aren't) and run a high quality coax.
RG58 is only OK for Coms and only over shorter distance. RG400 is better and
should be used for transponders or longer comms runs, RG223 is better still.

The best option is to run comms along one side and trim along the other.

Another note, those self adhesive pads are prone to fall off in time
(especially in the Ausie sun). If you must use them, prepare the bond area
as you would for any other bonding job ... Clean and abrade the area for
maximum mechanical bond.  

I intend to make little stirrups (bonded in line with the loom) that I can
use the zip-ties to mount the loom. To remove the loom simply snip the ties
and replace. The stirrups can be easily made by wetting out 2 or 3 layers of
BID and then laying this over a drinking straw leaving an inch or so either
side flat on a plastic sheet. Once set I cut them into 1/4" strips that,
from the side, look like the Omega symbol with elongated sides.

Paul Smith
Brisbane, AUSTRALIA
pk.sm...@bigpond.net.au
http://kr2spacemodulator.blogspot.com/


-----Original Message-----

I'm presently installing wiring in the aft portion of the fuselage,
specifically the trim actuator control wiring to the Ray Allen unit in the
elevator and the com coax to the copper foil dipole that will be on the
vertical stabilizer.   
My question is can I run them together in the same mounting clamps without
having an RF interference issue do to close proximity or should they be
separated? 


Reply via email to