[Elecraft] OT Apple Airport Extreme RFI

[Jim Brown]

On Sun,2/28/2016 11:24 AM, David Ahrendts wrote:
> Just replaced an older circa 2012 Apple Time Capsule with a new Airport Extreme in my home gigabit network. And in the category of “it’s always something,” I discover that the AEX powers down with my K3S/KPA500 at 500 watts. Just shits off.  Admittedly, they sit just feet away from each other, but care is taken to separate RF lines from audio lines and network lines. The newer AEX introduces Apple’s 802.11ac protocol. Any guesses?

First, take it back and get your money, and tell them why.

Second, if you decide not to do that, carefully choke all of the cables 
connected to it, following the guidelines in k9yc.com/RFI-Ham.pdf for 
ferrite common mode chokes for the ham bands where there is a problem.

Proximity between transmitter and the box doesn't matter -- transmitters 
themselves don't radiate. What matters is proximity to ANTENNAS -- 
that's what radiates. The cables connected to the Apple box can act as 
both TX and RX antennas, including the power supply, which itself can be 
a powerful noise source.

Also, be sure to listen for RF trash. The good news is that the chokes 
you install to protect the unit will also reduce trash radiated by those 
cables from the unit (and from the power supply).

73, Jim K9YC