On Tue,9/8/2015 9:24 PM, donovanf@starpower.net wrote:
That "growly" signals you're hearing are harmonics of your transmitted
signal generated by unintentional radiators, especially switching power
supplies. This type of RFI -- sometimes called "flooding" -- is caused
by solid state devices flooded by intense RF fields (your transmitted signal)
in which they were not intended to operate.
Great info! I've often heard this stuff, and wondered about the
mechanism. It makes perfect sense. Thanks, Frank. Some questions.
1) Have you run into this with linear power supplies?
2) Do common mode chokes on wiring connected to these sources provide
suppression? (In the case of rotator controllers, this would, of course,
include the control cable to the rotator, and for all devices, the AC
line cable).
3) Are conventional AC line filters effective for the power line
component? What I'm really asking here is, "is the coupling to the noise
source common mode or differential mode or both?"
73, Jim K9YC
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