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0 pointstreesknees4y ago0 comments

I don't think that makes sense at all. One major part of Part 15 from the FCC covers this. A device would fall under the category as an intentional radiator in part 15.1. And in part 15.23, considered a home-built device.

§ 15.23 Home-built devices.

(a) Equipment authorization is not required for devices that are not marketed, are not constructed from a kit, and are built in quantities of five or less for personal use.

(b) It is recognized that the individual builder of home-built equipment may not possess the means to perform the measurements for determining compliance with the regulations. In this case, the builder is expected to employ good engineering practices to meet the specified technical standards to the greatest extent practicable. The provisions of § 15.5 apply to this equipment.

https://www.ecfr.gov/current/title-47/chapter-I/subchapter-A...

This entire part from the FCC basically states you don't need a license to operate in the frequencies for wifi, bluetooth, etc. You're not breaking a law by recompiling the firmware for your wifi module to fix a bug. You'd be breaking the law if you did so with the intention of operating within licensed spectrum/power levels, for example.

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p_l4y ago

The problem starts with the fact that the device doesn't have any way of showing that it was modified, and some of the frequencies involved are license-restricted (especially in 5GHz wifi bands - 2.4GHz is dumping ground free-for-all because of aircraft ovens anyway).

So, let's say you modify something with your own firmware, break rules about ISM spectrum - or worse, mess with SDR hard enough you break some licensed spectrum, and upon investigation FCC certification marks are found and the number. Since certification points to vendor, vendor now has to explain why their device went outside of those limits, and might or might not be able to prove that you ran it with unlicensed firmware.

So an obviously home build device will go under §15.23 easily, but inconspicuously modified commercially sold device won't - without possibly long court case, that is.

franga20004y ago

The FCC is very familiar with inconspicuously modified commercial devices - hams have been doing it since before "firmware" was even a word. The fact that it's replacing some code on a chip instead of a shunt resistor on a PCB really doesn't make a difference.

And if this really was really the main issue, it seems pretty easy to just sign the firmware - I'm pretty sure many vendors do it already.

p_l4y ago

Vendors also want to comply with slightly different rules all over the world, and ultimately the easiest way becomes to sign and verify.

The code being secret is more of "trade secrets" than anything legal.

j / k navigate · click thread line to collapse

0 pointstreesknees4y ago0 comments

§ 15.23 Home-built devices.

(a) Equipment authorization is not required for devices that are not marketed, are not constructed from a kit, and are built in quantities of five or less for personal use.

https://www.ecfr.gov/current/title-47/chapter-I/subchapter-A...

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p_l4y ago

So an obviously home build device will go under §15.23 easily, but inconspicuously modified commercially sold device won't - without possibly long court case, that is.

franga20004y ago

And if this really was really the main issue, it seems pretty easy to just sign the firmware - I'm pretty sure many vendors do it already.

p_l4y ago

Vendors also want to comply with slightly different rules all over the world, and ultimately the easiest way becomes to sign and verify.

The code being secret is more of "trade secrets" than anything legal.

j / k navigate · click thread line to collapse