[sdiy] Advice for selling gear: FCC part 15 certification?

[Magnus Danielson]

From: "Bret Truchan" <clone45 at hotmail.com>
Subject: [sdiy] Advice for selling gear: FCC part 15 certification?
Date: Tue, 17 Jun 2003 12:16:51 -0700

> Hello again!
> 
> You all rule!  Thanks for being so friendly!
> 
> Eric, of Metasonix, was kind enough to warn me that, if I ever want to sell 
> my creations legally, I'll need FCC part 15 certification.  I was wondering 
> if anyone has any more inforamation about going through the certification 
> process.

Well, I have taken products through CE and FCC tests. Originally the stuff where
not up to standards, but that was way back in time and no thought went into it.
You can actually solve much of it fairly simply once you've learned the tricks
of the trade (and I don't mean cheating!).

>  It looks expensive!!  If I'm probably going to sell less than 50 
> units, and they don't cost much,  how can I break even?

This is a bit troublesome. The rulebooks is made for massmarket products, which
is the main bulk of products anyways. If you look carefully you might see that
the detailed requirements is quite different. Some stuff needs certification
before hitting the streets while other stuff needs it IF someone learns that
there is a problem, so then you buy yourself an insurance by doing the cert. at
a propperly certificated lab. You might need to check which rules works for
which market.

What makes it expensive is if you have to do much patching to get it through.
You might even need to go back and redesign stuff and come back a second (or
third) time to the EMC lab.

Depending on exactly how your product works you may have to run different
suites of tests. It's not all radiated emission you know.

I recommend you to get the FCC text and equalent EC texts.

If you have a possibility to learn from someone else and sniff radiated and
conducted fields off your box, then you can learn alot. If you are EMC aware in
your total design you can fairly cheaply fix much before it become an anoyance
in the lab. In the end is it just about common sense, but you have to learn what
common sense means in this respect.

> One piece of music gear that I'm thinking of making uses a microcontroller 
> -- and that's about it.  If the microcontroller already has passed FCC 
> approval, do I also need to have my unit approved?

How can a microcontroller pass the FCC test as such? Seems a bit silly really.
It is a _design_ which needs to meat approval. In the USA any digital device
with a clock frequency over 9 kHz (which indeed can include some analogue
modules!) needs to investigated further. The FCC text (In Code of Federal
Regulations - it's on the web in PDF format) is actually worth reading.

> If my gear is entirely composed of off-the-shelf components, do I still need
> certification?

Yeap, it is the end-product which needs to meet the approval. You can get both
battery, inductor, capacitor, diode and switch which each can pass a FCC test,
but put them together and you can have a quite powerfull little transmitter and
this would certainly not pass the FCC test. It's really common sense, ofcourse
it only helps to have components which behaves well, but in the end it cannot
be anything else but the total design. That is what is being sold and that is
what is going to be used out there in the reality.

I have a few good books listed on my book-page which helps in EMC issues.

Cheers,
Magnus