[RFI] Ferrite Question...

[Jim Brown]

On 6/20/2014 4:53 AM, David Cole wrote:
> What is happening here, any ideas?

First, because it's off-center fed, it's wildly unbalanced, so there's a 
lot of common mode current on the feedline, which makes it part of the 
antenna. The path for that current is through the tuner to ground.

Second, I'm guessing that he didn't wind turns through the ferrite 
cores, simply clamped them on. That adds inductance to the common mode 
circuit, which changes the tuning.

Study k9yc.com/RFI-Ham.pdf

73, Jim K9YC