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Comment by noonespecial | Hacker News Reader

I'm encouraged to see that projects like these are at least becoming aware that they will face challenges getting FCC certified as intentional radiators (and are required to in the first place!) but I still think they might be underestimating this difficulty. I've seen projects burn $90k going back to the testing lab over and over tweaking this and that to get within acceptable specs only to find when they went to production that a few key things on their BOM were discontinued by suppliers and they essentially had to start over.

Best of luck to them.

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It looks like they are using TI chips for the wireless (CC1101 for prototyping but it looks like they are targeting the CC1200 for release).

The have a little more technical information on their website - http://www.flutterwireless.com/press.html

http://www.ti.com/product/cc1101 http://www.ti.com/product/cc1200

Thats actually a really good choice. Like choosing the LTS version of your distro to develop on. Things have definitely gotten better than the "bad old days" my war stories are from. These new integrated radio-on-a-chip are much easier to deal with and manufactures are taking their reference designs seriously with an eye toward helping smaller projects clear these hurdles. Using TI instead of obscure-asian-manufacturer is also a good choice.

That said, if they're depending on ($80k - kickstarter fees) alone to get off the ground, I think that's a bit sparse. Then again, they seem to have done an above average level of pre-campaign development.

still waiting for chips which do DSSS (http://en.m.wikipedia.org/wiki/Direct-sequence_spread_spectr... ).

We can do DSSS, but our radio engineer (google Earl McCune) advised us that FHSS, while in some ways more complex (actually he just said it's tricker to design "right", which I'm fine with), will be vastly better for rejecting interference and intentional blocking.

interesting. does he mean frequency hopping ? if yes then i would not immediately agree however...

edit: i'm not a radio engineer just saying based on practical experience.

edit2: just googled . congrats on having this guy on your team.

Thanks! He's a serious silicon valley radio expert. He actually was a member of the homebrew computer club and brushed shoulders with Woz and Jobs before spending the rest of his career advancing radio in silicon valley. He helped lab test my designs, and he's really been an asset in verifying that what I think I did right, I actually did (Texas Instruments has some really great reference material). We experimentally verified on his equipment that my design basically exactly matches the performance characteristics of TI's reference design, and one of our RF component suppliers offers a $600 service where they put your device in their RF chamber to test emissions, which the engineer told me is a much better deal than you'd normally get at that price, but they only do it to help customers get off the ground. Before launch we spent a lot of time speaking to a lot of other professionals and kickstarter folk who have gone through the certification process, and it sounds like it's going to be manageable, especially with Earl McCune's help! I've done all the work on my own, but having a reliable expert is extremely critical in making sure the hardware will not be a problem!

If someone who'd designed a radio board wanted to understand more about getting FCC certified, where would you point them?

I believe this is the reason Wifi USB dongles are so ubiquitous, even in other electronic devices.

In general, the more modularized you can make your "politically inconvenient" technology parts the better. The trouble with "but with a radio integrated!" projects is that when you change any other parts on the board, you are required to re-certify the entire thing, even if the radio portion hasn't changed. This spells trouble for fast-moving "versioned" parts like ARM cpus, especially when you're small scaled and the version you're on might get discontinued next month.

The chips broadcast right in the 70cm ham band (440 MHz). If you're a licensed ham, then you don't need FCC certification and can just build one yourself :-).

Of course, then you can only sell to hams...

All the embedded projects I ever did with radiomodems on them (quite a few, including a laser game and associated hardware) had the radiomodems on them as daughter boards for that exact reason.

Atmel has been really good about supporting CPU footprints over many generations (their customers don't like redesigns either), and the FCC rules seem to give you a pass as long as you haven't changed things electrically. There's actually a reasonable amount of wiggle room - basically if there is no reason a board should perform differently, they say it doesn't need to be recertified. (at least, that's what they say)

That said, our goal is to brave the waters of the FCC to provide quality radio products to the open source community. If we succeed in getting funded, we should be able to handle the occasional new testing needed for any product changes.

We have some higher volume plans which will help pay for that. Arduino is only part of what we're doing. :)

This all started because there weren't any open source module designs for the CC1100 radio, so I made one and put it on github (actually I was using the 2.4ghz CC2500 at first). Eventually I slapped an arduino on, and boom, useful thing!

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