elveax:
The sticking point in what we were talking about is whether or not I could submit a device that transmits over RF as an unintentional radiator if the radio device already had an FCC ID.
It seems reasonable to me that even if the radiating component (an Xbee module, say) is itself FCC certified, since the finished product is an intentional radiator, then the finished product as a complete going concern should be tested as an intentional radiator.
Whether or not that's the actual case I can't say, and sparkfun's and my fellow ham OM Paul's opinions do seem to differ. I'd trust someone who has been a radio ham since the year before I was born to have a bit of an understanding of the way the FCC works.
elveax:
I think I have learned everything I needed to know at this point.
I would imagine there's a whole economy based on doing these certifications, and I think you'll soon be at a stage where money has to change hands for a professional consult on how best to proceed.
Paul was a bit rude. We were having a perfectly cordial conversation as I tried to parse the difference between what he thought was true and what Sparkfun was saying was true (which, we agree, differs), when he said:
"I don't know how I can explain this any simpler than you cannot FCC certify a product without making it operational and being tested in a certified lab."
Which, under the circumstances, was rude. I didn't need him to 'explain it any simpler'. He seems to not be aware of the difference between intentional and unintentional radiator testing.
And that's OK - I was unaware of the difference until tonight as well. But, he didn't have to act like I was stupid because I was trying to figure out the difference between the two, when he didn't understand the difference either.
And, for what it's worth, the internet seems to agree with Sparkfun.
"So taking the WiFi shield as an example, the module shown above circled in red is an intentional transmitter, i.e. it is designed to transmit on a particular frequency band (in this case 2.4 GHz ISM band). The device is certified to make sure that its emissions are within FCC specifications and it is issued an FCC ID.
Now at this point only the module is certified and is good to be used in a product, however, now that it is on a shield with extra circuitry added to it, the extra circuitry could be unintentionally transmitting. So now the whole shield is tested to make sure that the added circuitry does not have any emissions exceeding the FCC specifications and is issued a Declaration of Conformity."
There is absolutely no doubt in my mind that someone who's been a ham for 60+ years knows the difference between intentional and unintentional transmissions, but let's leave that, it's irrelevant.
But here's the tricky part and is where there's room for interpretation, and is where you might be making a leap of faith:
Now at this point only the module is certified and is good to be used in a product, however, now that it is on a shield with extra circuitry added to it, the extra circuitry could be unintentionally transmitting. So now the whole shield is tested to make sure that the added circuitry does not have any emissions exceeding the FCC specifications and is issued a Declaration of Conformity.
The added circuitry might cause an "otherwise healthy" certified radiator, or more correctly your finished product to exhibit some unintentional radiation. No argument there.
But, the presence of that intentionally radiating component (individually certified or not), and the stated or obvious purpose of the finished product, makes that finished product an intentional radiator. Its job is to radiate rf, that's why folk will buy it. Therefore it would be reasonable to me that it needs testing as an intentional radiator.
The above quote doesn't say that's not the case: it says that the problematic radiations may be unintentional, but that doesn't change the stated purpose of your product from an intentional radiator to an unintentional radiator.
And to me it's the stated purpose of the product, not the fact that the problematic radiation is unintended, that would define the product's certification category.
You're not reading the entire text. I quoted a small section of it, but combine what it says there with this section:
"Devices that are not intentional transmitters, only need to get a verification. What this means is that the devices is not designed to transmit anything and is test to makes sure that it indeed does not. If you pass the verification you are issued a Declaration of Conformity basically stating that the device is not unintentionally transmitting any frequencies."
So, a, Declaration of Conformity is what you get when you pass an unintentional radiator test. Then, later:
"Now at this point only the module is certified and is good to be used in a product, however, now that it is on a shield with extra circuitry added to it, the extra circuitry could be unintentionally transmitting. So now the whole shield is tested to make sure that the added circuitry does not have any emissions exceeding the FCC specifications and is issued a Declaration of Conformity."
So, I take the transmitter, I add it to my device, and have it tested as an unintentional radiator and get a Declaration of Conformity.
Combine that with what Sparkfun said:
"Some transmitters come with an FCC ID on them. Does using these devices exempt me from further testing to achieve FCC authorization?
Not entirely. While it does lower the bar from the costly Certification process, you are still responsible for ensuring that your product does not emit other radio frequencies. In short, you must test it as though it were an unintentional radiator."
It's not really me taking a leap of faith at this point - the research seems to bear out what I was saying pretty clearly.
I was googling around for FCC approved transmitters and found this blurb, also, when talking about the nRF24L01+ IC:
"To avoid tens of thousands of dollars in certification costs you can use a pre-certified nRF24L01+ module such as Talon Communications® so that like your Sierra Wireless Module you place a label on your final product that states "Contains FCC ID...". You will still have to pay for FCC testing for the unintentional radiator i.e. the non radio frequencies above 9KHz but this is far less costly than certifying your entire product as an intentional radiator as Talon and Sierra have done."
I've been through the approvals game a few times for stuff I've designed in the UK.
For simple stuff ( such as a car remote ) it cost < £1000 . Given you're employing two qualified guys, a load of precision calibrated equipment including antennas etc on an approved test site for 1/2 day, that seems not unreasonable.
You get a load of documentation which when submitted will get you an approvals certificate.
More complex devices, such as mobile phones, are more expensive - but the testgear is far more complex.
Allan
edit:
ps . Interestingly, the ETSI specs for a car remote are far more lenient than the FCC ones.
ETSI say less than -6dBm erp with a 0dBi antenna, the FCC say so many uV/m at 10m ( I forget how many) but it works out at >10dB less.
Also note that the typical 433MHz super-regen cheapo receivers commonly advertised can easily radiate -20dBm !
So, I take the transmitter, I add it to my device, and have it tested as an unintentional radiator
you must test it as though it were an unintentional radiator
You will still have to pay for FCC testing for the unintentional radiator
Except that your complete device IS an intentional radiator, and it would make perfect sense, notwithstanding the previous certification of the bits inside, that it needs testing as such.
There's only one way to find out for sure: take your gizmo along to the FCC, tell them what it does, and what's inside, and ask them what category they think it should be submitted in.
On a side note: the whole open source licencing thing brought up above, and which is independent of the FCC side of things is a scary area.
I agree that the entire device is clearly an intentional radiator - if it's a garage door opener or remote control or whatever, it clearly transmits RF waves.
But, the consensus here appears to be that you CAN get an FCC approved transmitter module, then add it to your device and get by with an unintentional radiator test. That's because the transmitter module is the intentional radiator, and it has already been tested. The unintentional radiator test for the whole device verifies that nothing else fishy is going on, and assuming nothing is, you get a Deceleration of Conformity.
If you can find anything that disputes this other than your gut feelings, I'm all ears.
Otherwise, I only originally objected to being treated like I was being dense as I pieced this puzzle together. Again, if you don't know the answer, then just don't answer.
Although I live in the UK I have put stuff through FCC for both an intentional emitter and unintentional emitter.
I think the sparkfun article is misleading. You do get savings in that you do not have to "buy" your intentional emitter "number" that has to be marked on the case, you use the FCC's number for the approved transmitter. However, the testing still has to test the "quality" and power of the intentional emissions, something that does not have to be done for an unintentional emitter. The product label is an important part of the product and has to be of the correct form.
Did you know that the schematics of every intentional emitter are published by the FCC and you can look them up on line?
However, the test house will make the decision for you if you tell them what you are doing. You do not just rock up and tell them what tests you want doing. Well you can, but be prepared for the FCC to kick that back to you. The whole process can take up to a year despite what they say.
Incidentally it was said in this thread that you have to have UL approval, that is not true. UL approval is only optional although some insurers might say that their insurance is not valid if you don't. But they will only say that if you try to make a claim and they are trying to wriggle out of it.
The FCC imposed a very hefty fine for one German company who changed the colour of the LED on a device and did not have it retested.
elveax:
If you can find anything that disputes this other than your gut feelings, I'm all ears.
Here's something:
Grumpy_Mike:
the testing still has to test the "quality" and power of the intentional emissions, something that does not have to be done for an unintentional emitter.
That makes perfect sense to me and is what I'd expect: it's not impossible that your circuitry may upset the quality of the intentional emissions of the previously-found-good-when-tested-in-isolation rf module that you bought off the shelf.
The FCC imposed a very hefty fine for one German company who changed the colour of the LED on a device and did not have it retested.
That seems a little extreme, although technically they were correct. I doubt if the colour of the led made any difference to the certification, but the only way to know that is to test.
