Deep morass involving CC2511F32 microcontroller and the FCC

Did you send your device to a "Test Lab" for FCC compliance tests? If so, do they have any comments or suggestions? Sometimes they may have good suggestions.

Hello Randy,

Your ultimate solution would be to use one of the certified mini development kits available from TI.  They come with the FCC ID.  Then interface it with your other hardware.  Another option would be to upgrade to BLE CC2540 or the CC2538 which has proprietary mode.  The CC254x devices will require an investment in software while the CC2538 is slightly cheaper but you require some additional hardware for programming.

Have a look at the Wireless section in the http://estore.ti.com for some of the development kits available.  There should be kits for the CC2510/11.  This all depends on the type of volume you intend to do of course.

The following three post may help you in deciding which route to take.

http://processors.wiki.ti.com/index.php/How_to_Certify_your_Bluetooth_product

http://e2e.ti.com/support/wireless_connectivity/f/538/t/352318.aspx

http://e2e.ti.com/support/wireless_connectivity/f/538/t/73909.aspx

Thanks,

Note: if you were to provide isolation on power supply, your inputs and outputs, these measures should eliminate any effects on RF.

No I haven't.  Finding that the whole process could cost me $10000, there is no sense in my proceeding further with something i can't afford without first finding out more about the likelihood of anything with the CC2511F32, and TI's recommended board layout passing. I was hoping, I guess, to get some counseling from TI, but all their contact links lead to the forums, so I guess they don't really care about supporting their customers very much.

I appreciate that,  and I will look at the links you've sen. But what I was hoping for was some help from TI, to understand the specifics of FCC certification with the CC2511F32 I've actually employed. Any solution involving scraping the whole project and starting over with a new MCU is not something i can consider. I might as well be asking for help learning to play the guitar, and have taking up the piano as a suggestion. That may sound extreme, but that's what it sounds like when you've invested a year of coding, laying out and cutting PCBs, and packaging and labeling, old to have most suggestions point you to starting over with a new core device.

Bottom line, have a product I'd like to market, based on this TI chip, and was hoping for some help from TI specific to that chip. Throwing everything out and starting over is always a solution. Seeing how an existing project, and its associated time and money invested can be salvaged is more of a challenge. I'm just dissapointed that all "contact us" links on the TI site lead to forums. Not that the forums aren't visited by TI engineers, but I need specific help with TI chip I've used.

BTW, the CC2511 EMK USB Dongle from TI has certification except for Japan. http://www.ti.com/tool/CC2511EMK.

It is basically the same as the Pololu.  As I stated before, if you use isolation on the power supply and I/O, you will not be affecting the RF.

greenja,

Well thanks for the sympathetic ear. :-)  I have been speaking to pololu and they have offered some useful info. But to your last point first, they seem to be under the impression that because their WIXEL comes un-programmed, getting their product certified wouldn't help because it would be completely different in behavior once an end user puts in code. Otherwise, at least according to them, they certainly would go through the process. I countered, however, suggesting that if they simply had one of their existing radio applications certified, other developers could easilly claim their code is now in the category of a "minor modification". This would not be stretching the truth much, IMHO, because after all... I seriously doubt that anything would cuase more radiation then their  "wireless serial port" app (which is one of their canned apps).

Anyway, I do know that because all my "transmitter" portions of the project (there are 2 ) run ONLY on battery, this supposedly takes me one step closer to a possible exemption. Pololu also shared with me something like you suggested. That is, one of their customers has reported to them some interesting counsel from an attorney. Apparently, by selling your product but stipulating that the WIXEL component is supplied "FREE" with the purchase, and also something about letting customers agree to be "business associates" in the sense of testing and providing feedback. 

I'm sure there are some tricks I could do for a while, including the old "for educational purposes only" statements of use. And frankly, this is a project that I'll eventually need investor capital to make in bulk anyway. But the whole thing burns my tail. Its my understanding, in fact, that even if you put a PIC chip in a box to control a few LEDS, you need FCC certification to sell it.  So as an engineer, I'd better hope some of my more "analog" projects make me some money. I guess only China can get away with selling electronics over here, basically just making up anything they want about FCC certification, and putting it on a label. Anyway, thanks again for lending an ear.  </RANT>

Hi Randy, 

The cost of development and FCC/ETSI/IC certification of an RF design vs. the added incremental cost of buying pre-certified modules does intersect at some point, and for low volume project modules will usually be the cheapest option. That being said, you should not have to spend $100K to certify two boards for FCC. I would advice you to check with a couple of different test-houses and I fully expect you to see a significantly lower quote. 

The point of our FCC certified reference designs is that you know that if you copy it _exactly_, you will also pass FCC with no issues. Any changes to or close to the RF part of the design, as well as changes to board type or stackup will put that at risk. To keep cost down at the test-house and avoid PCB spins, you should make sure you stick to the chosen reference design as closely as possible. 

There's an appnote on RF design review here: http://www.ti.com/lit/an/swra367a/swra367a.pdf

Peder

Peder,

Well if I said 100K, I meant to say 10K, and I got that figure from this informative discussion on the Sparkfun website...

https://www.sparkfun.com/tutorials/398#comment-53dfc8df757b7fb6278b4569

But when i consider that with all the cost cutting measures I've made, all along the development cycle, it is not a stretch to say that 10K more then doubles all my investment so far. And as I have two versions of a transmitter, and one master receiver, that's figure doubles again. I have, as much as possible verified that the WIXEL module I chose does conform to the reference designs TI has offered, and I think its doubtful my product wouldn't comply. But I had hoped to find a way to at least test market a few dozen items, to at least make sure its as useful and marketable as I'd like to think it is, before even considering a fraction of those numbers. It would really hurt to finally get certification, only to have a test market reveal a significant modification is required. This  happens, and its proof that the FCC has gone too far. There should be exceptions in place to allow a reasonable number of a new product, with a certain low threshold of RF radiation, in certain designated bands, to be marketed without official certification, provided there are no complaints. Things must have changes a lot. As a Kid I ran neighborhood "FM radio stations" using nothing more than a radio-shack kit, and easily covered a half-mile or more. Now I've built something with a chip that can barely transmit 50 feet, on an a amateur RF band, with virtually no risk of interfering with any service... and yet all this headache and expense!

Greenja,

I guess the last time I visited, I didn't notice your post about the CC2511EMK. Your right... i does look a lot like the Wixel, and is probably the antenna design that pololu referenced. As an aside, I have heard personally from a TI rep who said that pololu's design differed slightly, which kind of contradicted Poolu's documentation, which i confronted them about, and they said that while they can't promise a timetable, my requests as well as others has moved them to consider getting the wixel certified. 

But that's secondary. The EMK looks to be similar enough that *IF* it is indeed a certified design, its possible I might be able to re-design my products to use that board. I've inquired of TI about it so we'll have to see. The main issues are whether it is indeed a certified design (otherwise I'm no better off then I am now), whether TI has locked out any possibility of re-programming the module with an updated version of my app, and most importantly, whether they would furnish these at a price somewhere around Pololu's wixel. The wixel, if you go for a "Black Friday" sale in December, can be had for as little as $12, without buying huge quantities. If TI would be be willing to come down some from their approx $50 /each on a quantity order, I might be able to make this work.

FYI:

Have a look here for info on CC2511EMK FCC:

https://apps.fcc.gov/oetcf/eas/reports/ViewExhibitReport.cfm?mode=Exhibits&RequestTimeout=500&calledFromFrame=N&application_id=660392&fcc_id=ZAT2511USB

That link doesn't work Eirik, but thanks anyway. The broken link offers another link to report the problem, which I did, but if it works for you let me know. Maybe its a form your company submitted, so you're allowed to see it, but I don't have permission?

Hello Erik,

Now this is definitely a useful link to have.

Hmmm... if someone wanted to know just what you guys where up to, could they enter in product or other information and get details prior to product release?  ;-)

What is especially interesting to me is that close examination of the the PC trace antenna tells me that THIS is the product Pololu based their WIXEL on. At elast I'd be willing to bet on it. And after my prodding, Pololu said they are willing to re-consider trying to get their WIXEL certified, Well I'm sure they didn't even know that that TI got this product certified, passing all FCC tests and getting some exceptions approved, just last November (2013!).  I've sent them this information, and I'm hopeful it may inspire them to expedite getting their WIXEL certified. Even if there are slight deviations, its at least a safe bet that it will pass if they invest the time and funds to get it done.

LOL!!!

I'm sure I had someone worried for a few seconds :).

Actually there is  an option with FCC to counter just that (just in case somebody else who plans to certify their top-secret project reads this). You can ask for confidentiality for a certain time period (I beleive it is up to 1 year), in which case FCC will not make any of your documents publicly available.