This question has been asked multiple times but I don't see anyone quoting hard evidence.

  1. This link states that all devices that oscillate above 9 kHz need to undergo certification. (I would leave a comment on this question but my low reputation forbids me to do so)
  2. This link (see ka7ehk's post) states that only compliance is required but certification is not necessary

However, neither link quotes from 47 CFR 15. So, my question is if FCC certification is required in the unlicensed bands in the USA? If so, where is the exact section in the 47 CFR 15 that states this bit of information?

PS: I'm going to start looking deeper in 47 CFR 15 but if anyone is super familiar with the spec, that would save me (and many other engineers in the future) a ton of time.

  • 1
    \$\begingroup\$ Not familiar enough with FCC regulations to post as an answer but my understanding is that if you have a transmitter for your own use / prototyping if you comply with emission limits there's no problem, although you could be liable if it doesn't comply. However when selling an intentional radiator proper testing is 100% required so a small localized problem doesn't become a wide-spread one. That's possibly why some forum threads will have mixed answers on what is OK. \$\endgroup\$
    – PeterJ
    Commented Feb 12, 2015 at 11:05

2 Answers 2


Absolutely it is required, I assume you are talking about being a radio in the 915Mhz band? In which case you will be an intentional radiator and will need to go through compliance test at an actual test location, and register the device to get an FCC ID, which you must then apply to your product.

The specific section you are interested in is FCC section 15.249, here is some more information about it from the FCC.

Here are some good app notes, one from TI the other from Semtech.

You'll see that there are also power limits for simple transmission, and higher power limits if you're using spread spectrum.

You will also of course have to pass FCC Class A or B depending on your equipment type.

Edited to answer questions

I'm no FCC or legal expert and you should probably consult one or more of those and a test house. However if you look here you will see the FCC guidelines to "Determine if device requires authorization under Verification; Declaration of Conformity (DoC); or Certification" Where they say for "Unlicensed transmitters (low power intentional radiators) – see Section 15.201"

Paragraph 2 of that section says

"Except as otherwise exempted in paragraph (c) of this section and in §15.23 of this part, all intentional radiators operating under the provisions of this part shall be certificated by the Commission pursuant to the procedures in subpart J of part 2 of this chapter prior to marketing"

Now subpart J of part 2 states:

"§ 2.907 Certification. (a) Certification is an equipment authorization issued by the Commission, based on representations and test data submitted by the applicant."

That's your section saying you must apply and provide data for certification, you can read subpart J to learn more about how that testing should be done. I suppose you could collect the data yourself provided you have access to the tools (and shack or are in a valley somewhere with no interference), and that you can follow an acceptable test procedure. A little more digging will show how you have to apply along with the fees.

Or you could go to a test house and pay them, which is what most people do.

  • \$\begingroup\$ Thanks for the response! I understand that 15.249 has the rules and regulations for operating a 915 MHz radio. However, my question was if certification is required for a 915 MHz radio and where is the relevant section. My confusion is if compliance (e.g. I verify that my product doesn't break any rules in 47 CFR 15 through some lab testing) is sufficient or if I need to go through the FCC to get an actual stamp. \$\endgroup\$
    – rith87
    Commented Feb 13, 2015 at 2:13
  • \$\begingroup\$ @rith87 Verifying that your product doesn't emit unwanted emissions via lab testing will get you an FCC ID (stamp as you call it). Compared to the cost of testing (many thousands of dollars) any FCC fees will be minimal. \$\endgroup\$
    – tcrosley
    Commented Feb 13, 2015 at 4:55
  • \$\begingroup\$ Agree on that intentional radiator testing costs way more than just class b too. I updated my answer to point you to relevant docs, but forgot to leave comment about it. \$\endgroup\$ Commented Feb 13, 2015 at 5:01

It has to be certified because of potential interference with other users such as ISM (Industrial Scientific Medical) users. 915 Mhz is also the center frequency of a Radio Amateur band (902 -928 Mhz). Those unlicensed users have to operate a very low power output.


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