Is it legal to transmit using HackRF one (in Germany), the purpose is to do some Lab research and Academic experiments.

for example i want to broadcast an FM signal using HackRF one and try to receive it using another hardware (RTL-SDR).

If no is there another legal alternative?

  • $\begingroup$ Do you have to actually transmit, or can you make do with a cable, some attenuators, and perhaps a noise source? It won't behave like a real RF channel, but maybe that won't matter. $\endgroup$ Commented Oct 15, 2018 at 17:52

3 Answers 3


You'll need an experimental radio license (Versuchsfunk) from Bundesnetzagentur link for research operation.

For demonstration/teaching purposes, a demonstration radio license (Demonstrationsfunk für Bildungseinrichtungen) would be in order.

I'm not a lawyer nor have I ever applied for either of these; I'd recommend contacting BNetzA on these aspects. Whenever I contacted them, they were super friendly and swift.

A loophole here might (again, ask BNetzA if in doubt) be general low power transmitter licenses as used by e.g. the small dongles that you can plug into your iPhone to make your car stereo receive on FM what your phone is playing. I know that there's a pretty low power limit for these (nW range), but that might be perfectly suitable for your use case. What I don't know is whether the devices in question need to be type-approved (which would rule out the HackRF completely, as it can do anything) or whether guaranteeing that your device won't do anything bad is sufficient at these power levels.

  • $\begingroup$ Thank you Sir ... i am thinking also on maybe listening to some radio channel and work on that for the moment ... In fact the real thing behind my question is that if i want to try something else on the future like changing the modulation, add a channel coding, i have to find a legal way to do it myself ... But again Thank you. $\endgroup$
    – A.SDR
    Commented Oct 15, 2018 at 14:49
  • $\begingroup$ well, the path is pretty straightforward if you believe BNetzA's own documentation on the pages I've linked to above. $\endgroup$ Commented Oct 15, 2018 at 15:04
  • $\begingroup$ Is any of that needed for someone owning a amateur radio license and using amateur radio frequencies? $\endgroup$ Commented Oct 18, 2018 at 20:19
  • $\begingroup$ @ThomasWeller no, if you also use it for amateur purposes (the trifecta: · amateur license, · amateur band, · amateur usage), then you're fine. Note that amateur usage does include experimental usage, but can't include e.g. trying out your new commercial waveform. $\endgroup$ Commented Oct 19, 2018 at 11:10

As for other legal alternatives, one might be transmitting inside a suitably shielded Faraday cage. I’ve seen such facilities at labs where various prototype and pre-production (and competitors?) electronics systems were being tested to measure how far out-of legal compliance they were.


I've also seen things like this done with the two units directly connected via a section of coax instead of antennas on each. Of course, for this to work, you need to keep power levels very low and there may still be some "unintentional radiation" and in some cases you may still need attenuators inline.


You must log in to answer this question.

Not the answer you're looking for? Browse other questions tagged .