Yes, the fine is ~ as much as it would cost to get your design FCC certified; so its very cost effective as once certified for a design, its one and done. The good news its most often only the end product manufacturer who is responsible for emissions; the subcontactors or submodules are not necessarily involved unless these modules can be sold as stand alone products, .e.g. radio amplifiers. If you sell products as a kit, you may be able to circumvent most regulatory bodies, FCC, CPSC etc., as the assembler takes the responsibility. I think the FCC made exceptions for RF jammer kits, and can hold kit seller, kit assembler and even the designer, liable.
As for enforcement of the rules, it only becomes a problem usually if someone complains or your product becomes high profile [ then, as a backstab your competitors complain to the FCC]. If a device goes unnoticed for years then years later the FCC finds out, there is no statue of limitations, and they can provide the sanctions and fines retroactively for the years you had the device on the market.
Bottom line, the hassle isn't worth the cost of not getting FCC approved. If you are a subcontractor, insure your device cannot function as a turnkey device [ i.e., supply no power] so it cannot be used as it comes out of your facility without added work by the assembler.
... $10,000 per instance, aka per device, and goes up from there, and depending on the law, include jail time.
Ouch.
Testing looks more attractive, but it surely kills all profit margin on a low volume run. Maybe that's why they chance it? What does FCC testing normally cost? My fellow engineer said a couple thousand USD and a few weeks so long as it isn't a device that is body mounted.... apparently that requires SAR testing and is expensive?
Even some mid-volume products appear to violate rules. It's not too uncommon to see customer replaceable antennas attached to precertified modules. Some of those same assemblies don't bother to place the module's FCC ID on the outside of their packaging.
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