we have a product which has radio of 1W maximum output power , we have sent product for FCC through party lab, and they certified the product with 18 dbm only. So we get the certificate with only 18 dbm.

But in field we need to use more power like 25 dbm. So can we use this power even if we certified the module at 18 dbm or we need to repeat the whole FCC test again.

  • 1
    \$\begingroup\$ I'm pretty sure that to use it legally you need to repeat the FCC process. Of course, there's nothing stopping you from using it illegally, you just might get in big trouble if you do. \$\endgroup\$
    – Hearth
    May 2, 2019 at 12:40

1 Answer 1


When you have an approval and need to change something, you must be able to reason about if the changes will affect radio and/or EMC characteristics. In this case it's crystal clear: you have to repeat the test. Changing output power to something 5 times larger than tested is a very drastic change. There is no doubt that it will effect most of the radio characteristics, including out-of-band/spurious emissions.


Your Answer

By clicking “Post Your Answer”, you agree to our terms of service and acknowledge that you have read and understand our privacy policy and code of conduct.

Not the answer you're looking for? Browse other questions tagged or ask your own question.