There has been a lot of discussion about regulatory compliance on the announcement thread for these radios.

I thought I should explain a bit about why these radios don't already have compliance certificates, and what you can do to get involved in an effort to get them certified. I should first note that I don't work for 3DRobotics - I'm just a volunteer ArduPilot developer who happens to be very interested in these radios. I also wrote most of the radio firmware. So this is not an official 3DRobotics statement.

The basic idea with regards to regulatory compliance is that these are DIY radio parts. It is our understanding that, at least in the US and Australia, it is quite OK to use radios that comply with the relevant standards without getting them officially certified. Other countries have different rules.

So why didn't 3DRobotics get them certified anyway? Part of the problem is that the firmware is being rapidly developed, with new features regularly added. Under some certification systems that may mean re-certifying each firmware. That would cost a lot, and push up the cost of the radios.

The second problem is that there are so many different certification systems. There is FCC in the US, C-Tick in Australia, CE in Europe etc etc. Sometimes it may be possible to get quicker/cheaper certification of one type if you already have another type, but it is still complex.

So what do you do if you want to use/distribute these radios in a way that requires certification? I think the only reasonable answer is for the community to solve the problem. If someone puts their hand up to volunteer to do the legwork to get these radios certified in some area then they could share the results here and hopefully make life easier for someone else to work on certification elsewhere.

Meanwhile, if you post something about certification, please try to make sure you do your research carefully to make sure the information is accurate. If we can build a community effort around this then I think we can solve it together.

Cheers, Tridge

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Martin, I believe you can already get these from the UK, how are they managing to sell it?

3DR only makes the carrier board for the HopeRF module, I'm doubtful they could even certify it if they tried.  If they've applied for anything it will be in the FCC database...

Don't see anything.

Jake & Alan,

Thank you so much for the information and help, it's great that you have both added to this chat with some new ideas and possible ways to work with the radios and move this forward, I do have a question on the comments you both made in the last few posts, the "FCC" if I understand correctly is like our Ofcom here in the UK, these people that are in charge of enforcing the rules on the “equipment” used, they make sure that the equipment be it a cordless phone for home use or a HAM radio are within spec and not causing interference to other users on the same or local frequencies, so should the 3DR radio have / not have an approval certification in the USA with the FCC like is needed here in the UK with the CE mark? As in the last few posts it’s not the module in question but the sum of all the parts which needs to have the approval / testing?






Unlike the FCC, Ofcom do not test or approve any equipment, it is left to the person or company who place it on the market to ensure it complies. Apparently the 3DR radios are not listed with the FCC.

It is worth reading this.

Basically, you collect documentation for the parts from HopeRF and 3DR and subject the equipment to a test for electromagnetic compatibility (as I previously described).  These devices are very low power output and unless way off frequency are unlikely to cause any problem. Radio equipment needs to effectively use the spectrum and not cause harmful interference.

Here is one way round the situation and I have seen it used with other products. You supply the Radio and the aerial separately although they can be both bought at the same time. This is a kit as you have to assemble the aerial onto the board also connect the power supply and load software.

R&TTE Compliance Association TGN 02 Rev 1

Technical Guidance Note on Requirements for Radio Kits

The R&TTED requires that:

"Apparatus complying with all relevant essential requirements shall bear the CE marking. It

shall be affixed under the responsibility of the manufacturer, his authorized representative

within the Community or the person responsible for placing the apparatus on the market.

This includes the identification number of the Notified Body used, if any and the Alert Sign if


Apparatus shall be identified by the manufacturer by means of type, batch and/or serial

number and by the name of the manufacturer or the person responsible for placing the

apparatus on the market”

The manufacturer of the Radio Kit however has no real control over the assembled

equipment and requiring that the assembled equipment (at the user level) needs

identification and CE marking is unrealistic and unnecessary. Although the user is

responsible for the actual use and operation of the assembled product the user can not be

forced to apply any CE marking to the assembled product.


We in the UK have a dedicated frequency of 459Mhz for model control which is well away from the 433Mhz band and virtually unused. It would be really good to get them working on this frequency. I believe it can be done with software.

Hello Alan,

I have looked at the 459 band and the great news is these radios do work on it, Tridge and I had a Skype chat about this application a while back, however until I can get the import / sales / certification questions answered we can't move forward on this, however your help is helping me see a little light at the end of the tunnel. The 459Mhz band is already used by some RC controllers from the open source market, so all this is possible! :) I will be putting some more time into this today, I really would like to get this taken care of!

Your help is great Alan, thank you again.





It is possible that I could certify the modules.  If you think that a simple run on a spectrum analyzer is enough to tell that it is meeting the regulatory requirements I could do that at my university.

Someone also needs to check into the other firmware related requirements (duty cycle, hops, etc.).  A test firmware that meets these requirements would also be a good idea.  It will also have to hold one frequency long enough to settle and get a screenshot.

If it's as easy as it sounds I'd have no problem filing the paperwork under my business and certifying all the radios.  Too bad the FCC is so much harder to satisfy.

Any traction on this?  I'm curious too.

I'm in the US, so FCC stuff follows.

As I understand it, 3DR is staying this is DIY that allows us to utilize the 5 transmitter exemption the FCC allows, the rule for this is 15.23 and is titled "home built devices". It states "(a) Equipment authorization is not required for devices that are not marketed, are not constructed from a kit, and are built in quantities of five or less for personal use."

I don't think the 3DR radios would fall under that category.  I'm not clear where a "Kit" built unit would fall.  I'm not sure what makes something a "kit".  I don't know that the 3DR radios are a kit anyway, don't they come fully assembled and all you have to do is plug them in, attach an antenna and perhaps configure them?

I don't think they fall into the Amateur band either, although the Amateur band is allowed at 902-928 MHz.  It is my understanding that you must transmit your call sign periodically for compliance and that the operator must have a license granted by the FCC to operate a Transmitter.  I don't think the 3DR radios transmit a call sign, nor is there a provision to do so.

Those exclusions tend to push my thoughts that this is a 15.247 transmitter, or perhaps 15.249, or even 15.231 if the power level were much lower.

I've run a few transmitters through the certification process for each of these rules and am reasonably familiar with what's required...Top of the list, each of these require an FCC ID with a submitted report and a certification from the FCC.  An FCC label is required on the device...or if the device is too small, in the operating manual.

The process of certification is not easy and the measurements are difficult too...they require highly specialized equipment and even certified locations where the tests are performed.

It's not something that you can do "at home".

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