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We are currently evaluating a nRF9160 for a consumer/industrial product. It does not have a built in antenna for GPS/LTE. There are detailed specs on designing for an external one from Nordic. Now normally, my understanding is in agreeance of what @tcrosley wrote FCC Certification? in this answer. If the module has a built-in antenna, or a connector for an external antenna (and you use a pre-tested one) you can be exempt from FCC testing as an intentional radiator.

The nRF9160 seems to be different. According to: FCC TCB

This grant is valid only when the module is sold to OEM integrators and must be installed by the OEM or OEM integrators. This module can only be used with a host antenna circuit trace layout design in strict compliance with the OEM instructions provided.

My take on that document is that as long as you follow Nordic's design doc's, and you don't exceed the power listed, you will be exempt from certification as an intentional radiator. That goes against all of my past experience and really doesn't make sense to me, since:

a host antenna circuit trace layout design in strict compliance with the OEM instructions provided.

is very open-ended and could easy be done improperly, causing the module to fail a test, if it was tested.

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    \$\begingroup\$ "Installation of this device into specific final products may require the submission of a Class II permissive change application containing data pertinent to RF Exposure, emissions and host/module authentication, or new application if appropriate." might be relevant \$\endgroup\$
    – BeB00
    Commented Mar 26, 2021 at 20:47
  • \$\begingroup\$ @BeB00 Absolutely, I noticed that. But if that means all cases, then what in the world is the reasoning for the quotes that I included? And what "specific final products" would not require a Class II submission? \$\endgroup\$ Commented Mar 26, 2021 at 21:04

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I went several times in an Italian EMC compliance test lab for some tests and asked them a similar question regarding pre-certified modules.

The answer was:

if you put a certified module on a new system you save the most expensive tests of the certification but some tests must be done again.

For example, the RF output power test must be done.

If the new system has a built-in antenna, the output power test is done in a semi-anechoic chamber. They will ask you to configure your product in order to transmit the maximum RF power stated in the product's datasheet.

If the new system has a connector for the antenna then the test is done by a spectrum analyzer. No chamber. They will ask you to configure your product in order to transmit the maximum RF power stated in the product's datasheet.

If the new system has a connector and it is sold without an antenna, then the output power test must be done by the one who buys the system.


What happens if you cheat and pass the test?

I'll cite you 2 real cases:

  1. An Italian company, back in 2005, sold RF modules to an UK company. All went well for some years. One day, an UK company specialized in designing and producing RF modules, brought an Italian RF Module to the UK Chamber of Commerce which in turn brought the module to an EMC laboratory and discovered that the module's output power and the band were not compliant to the UK's regulations.

The bottom line is that the Italian company had to stop selling the modules in the UK and I don't know whether or not the company had to pay a fine.

  1. All Chambers of Commerce around the world monitors and test local and imported products. They bring selected products to Test Labs for compliance tests.

Do you remember what happened to Volkswagen in the US and the Dieselgate?


Nordic's modules are certified using a host system which is different from yours.

The EMC test lab told me: even if you copy the Gerber files and all, your host system is different from the system that Nordic certified.

The EMC test lab in cases like this, study the problem and then propose you a set of tests to be done. These tests are called "Delta tests", where Delta means difference.

Hope this helps.

Enrico Migliore

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    \$\begingroup\$ Makes total sense, and that has been my understanding for years. I just don't understand how Nordic and/or that TCB doc can claim that a custom trace -> antenna would allow it to not require close to a full re-cert.. \$\endgroup\$ Commented Mar 26, 2021 at 22:20
  • \$\begingroup\$ Regulations might have changed on printed antennas since they are not efficient. \$\endgroup\$ Commented Mar 26, 2021 at 22:26

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