I just bought a new XM2 yesterday. The first paragraph in the manual says I should attach these two Ferrite Cores to some video cables. I remember doing this on my orginal XL1 but not on my replacement XL1s.

So, I don't really know what they are for. I guess they're for stopping some sort of electrical interference.

The manual only says that they must be attached to comply with the Technical requirements of EMC Directive.

Why don't Canon automatically attach them? Or, is there a benefit to leaving them off? or does the manufacturer say attach them for "Legal Reasons"?

I had a old telephone that picked up FM radio interference once. I put one on the phone cord and it actually eliminated the problem 90%.

It is probably cheaper for them to have you put them on, because they don't give them to everybody.

Cheers,
-B

I have a GL2 but haven't read anything about Ferrite Cores. Am I missing something?

They may reduce RF that causes interference. Some countries may require that certain device accept the interference caused by RF or minimize the RF. Not all products, in all countries, will require the ferrite cores. The FCC, in the United States, may not require this level of protection, for the GL1/GL2. Regulations in other countries may differ.

Not sure but I think the cores work in both directions. It may be that the GL2 power supply induces more noise than is acceptable for the standards in your country but not others.

Ferrite cores do indeed work in both directions. My post is a little ambiguous. The effectiveness on some types of interference is debatable.