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How can I make my wireless card emit a specific frequency (the ones that it is capable of physically)? I am aware that a kernel module can help (please correct if I am wrong) but am looking for something like a command line tool.

How can I find the exact upper and lower limits? As the driver interacts with the device, hence kernel should have access to this information (although I understand this could be a soft limit. Is there a way to get the hard limit as I would like to avoid digging into the manufacturing details)

[Motive: Disrupt functioning of remote control at home (I know I can just take out the cells, but I want to do this in a grand way :P)]

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    Remote controls are usually IR, not RF. Are you confused, maybe? Jun 6, 2013 at 21:21
  • @sendmoreinfo IR and RF are the names given to a region in electromagnetic spectrum (A diagram: lumenistics.com/wp-content/uploads/2012/02/…). Even though the devices are manufactured to operate in certain frequency range, I am hoping that some of the devices are limited just by the driver/software. I don't know much about electronics, but I guess the limits are imposed by passing the signal via a band pass filter i.e. some extra circuit. So some manufacturer may avoid it. Perhaps, I could leverage that. Jun 7, 2013 at 6:53
  • This question risks being closed as off-topic, I think that's because it's too much about electronics. Maybe you can save it by rephrasing as a software recommendation question.
    – phunehehe
    Jun 7, 2013 at 15:07
  • You can use a software-defined radio to emit a specific frequency, but that will not make it emit IR signal. Jun 7, 2013 at 18:50

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Remote controls is normally either IR or RF.

IR usually operates in the 30-60 kHz range, typically 38 kHz and require free sight, send pulses of IR light to a receiver.

RF uses a much higher frequency, typically 300+ MHz and is used for various equipment that supports it like car locks, ports, home theaters (natively or using adapters) etc.

Your WiFi adapter most likely operates on the 2.4 GHz band, that is:

2.4000 to 2.4835 GHz - IEEE 802.11b, 

optionally the 5 GHz band

5.15  to 5.35  GHz and 
5.725 to 5.825 GHz - IEEE 802.11a.

Have no equipment to test on here but one have at least two alternatives.

1. The old iw tools.

  • iwlist List of available frequencies depending on locale.
  • iwconfig Set a specific frequency.

2. iw is the new and recommended tool to use with the official wiki at http://wireless.kernel.org/


aircrack-ng have some tools for various testing and proofing and auditing of your wireless network. As well as wifijammer etc. Heed the laws/warnings etc. for your region – and use your head. For IR-jamming you are out of luck using your WiFI adapter.

Check out things like Radio spectrum, ISM band etc.

It is all bound to strict laws. The 2.4 GHz band is popular as it is free, as in you do not need license or the like to use it – unregulated frequencies. It is part of the ISM (Industrial, Scientific and Medical) where Radiocommunication services operating within these bands must accept harmful interference, which may be caused by these applications.

It also depends on regions etc. The International Telecommunication Union (ITU) would most likely also be an interesting topic.

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    I would like to point out that infrared remote controls are usually 940 nanometer wavelength which translates to 319 terahertz. Jan 15, 2019 at 16:30

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