[RFI] Direct TV DVR problems

[Jim Brown]

On 11/3/2010 10:54 AM, doc at kd4e.com wrote:
> I am curious.  What is it about the content and manufacturing
> of toroids that makes them so expensive?
>

I don't know anything about the manufacturing process so can only guess. 
Here are some obvious things that come to mind.

They are quite brittle, so breakage is an issue with handling, and 
especially with packing and shipping. This increases cost.

Every single must be produced individually -- that is, you can't make a 
big one and cut into little pieces.The clamp-on parts must mate VERY 
closely, so their mating surfaces must be VERY smooth.

Each mix is a different chemical structure, and I suspect that small 
changes in the formula and in the production process must be avoided to 
maintain consistent electrical properties.   It may also be expensive to 
do this.

Based on the above, there may be yield and quality control issues.

73, Jim K9YC