See below.
Jon D. Curtis, PE
Curtis-Straus LLC [email protected]
One-Stop Laboratory for EMC, Product Safety and Telecom
527 Great Road voice (508) 486-8880
Littleton, MA 01460 fax (508) 486-8828
http://world.std.com/~csweb
On Thu, 13 Mar 1997, Peter Phillips wrote:
> Dear All,
>
> Could you please help me regarding obtaining approvals to FCC part 15
> for radiated emissions.
>
> Being a European manufacture complying to CISPR22 (EN 55022) I believe
> that the FCC will permit these limits to apply.
Yes, you can use the CISPR 22 limits provided you test using the ANSI
C63.4-1992 test procedures and test to the higher frequencies as outlined
below. Note that you must use both the radiated and conducted limits of
CISPR 22, you can't pick and choose among the FCC and CISPR limits on a
given product.
>
> However from what I understand products with internal frequencies lower
> than 108MHz must meet emissions limits upto 1GHz as per CISPR 22, but
> products with internal frequencies from 108MHz to 500MHz must have an
> upper measurement frequency of 2GHz, from 500MHz to 1GHz the upper
> measurement is 5GHz and for products with internal frequencies above
> 1GHz measurements should be made to the 5th harmonic of the highest
> frequency or 40GHz whichever is lower.
You are correct. Apply the FCC limits above 1GHz.
>
> Can anyone please confirm the above and let me know the levels that
> apply.
Class A 49.5dBuV/m at 10m Class B 54dBuV/m at 3m.
> Does Class A and Class B levels also apply?
Yes, but their are marketing restrictions which govern which limit to use.
Class A is for digital devices marketed to clients who will use them in
commercial or industrial settings. Class B is for digital devices which
will be marketed to home users. For PCs and peripherals you will probably
want to use a NVLAP or A2LA accredited test house (or one that has an
application pending) in order to use the new simplified declaration of
conformity approvals procedure for PCs and peripherals.
> >
> Thanks in advance
>
> Peter
>
