[RFI] Samsung refrigerator RFI

[Jim Brown]

On 8/8/2012 2:13 PM, Mel Crichton wrote:
> Any help out there? The warranty isn't expired yet, but I will be removing
> screws in the next few days. I may get lucky with some simple shielding
> (Already wrapped the AC cord in ferrites)

What do you mean "wrapped the AC cord?"  Do you mean that you clamped a 
bunch of them onto the AC cord, or that you wound multiple turns of the 
cord through a big ferrite core?  The former is unlikely to solve 
anything. The latter COULD make a big dent in the part of the noise that 
is conducted onto the AC cable.  Study my RFI tutorial for detailed 
recommendations.

http://audiosystemsgroup.com/RFI-Ham.pdf

Another important thing to check is where the green wire in the power 
cord goes inside box.  Make sure that it goes directly to the metal 
chassis, and that paint is not interfering with that connection. Also 
make sure that tall metal parts of the body and chassis are making good 
contact with each other, including the paint issue.

The trash is very likely to be generated by a variable speed motor, 
which is essentially DC chopped into pulses of varying width. If the 
layout of that wiring is poor it becomes an efficient antenna and also 
generates a strong magnetic field.  Good shielding can confine this 
shield inside the box, but poor shielding will result in a lot of noise. 
It could be a MAJOR project to fix the part of the problem generated by 
internal wiring.

Frankly, I think you're making a HUGE mistake by waiting until it's out 
of warranty. I would INSIST, VERY LOUDLY, and VERY PUBLICLY, that they 
fix it as a defective product.  It is defective because, according to 
Part 15, any customer MUST cease operating it if it interferes with 
licensed radio communications.

If you don't do this, you've just gotten screwed out of whatever you 
paid for it. And the only way this stuff gets changed is when customers 
make it sufficiently unpleasant or unprofitable for the company.  When 
we run into problems like this we owe it to our fellow hams to take 
serious action.  As we learned years ago in the civil rights movement, 
if you're not part of the solution, you're part of the problem.

73, Jim K9YC