GPS COMM cable interference?

[Greenley]

At the moment I have run 3 RG400 cables to the back of my plane, one for a COMM antenna, and two for GPS antennas. The cables are all in the same conduit. I have been told this will cause interference of the GPS signal by the COMM when transmitting, that the RG400 runs for COMM should be at least 6" from any GPS cable runs. My antennas are the proper distance apart, this is just a question about the RG400 being in the same conduit or not. I have searched the GTN650 install manual but have not found anything. Is this an issue, did I miss it in the manual?
Thanks

[Jesse]

You should be fine with RG400. I have never seen a problem with this, but if you have another location to run it, do so.