I just got an RTL-SDR dongle by Nooelec and am using CubicSDR on Mac (which supports AM, FM, and SSB), and I'm in Canada. I'm able to easily find FM radio stations, but outside of that I'm not sure where to look for interesting frequencies to listen to. (total newbie)

What frequencies should I try tuning into to find various types of signals I can listen to?

  • $\begingroup$ I'm sorry, but "what is interesting" is too subjective a question. A way to narrow down your question to be concretely answerable might be, for example, "What types of AM or FM [or whatever modes your software supports] transmissions can I find in most areas in [my country]?" $\endgroup$
    – Kevin Reid AG6YO
    Commented Mar 13, 2017 at 19:42
  • $\begingroup$ Fair criticism, but attribute it to Stack Exchange as these rules are network-wide. But I did suggest a change you could make to make your question non-subjective and have a reasonably sized answer — list the modes CubicSDR supports and specify what country you're in (as frequency allocations are not worldwide). $\endgroup$
    – Kevin Reid AG6YO
    Commented Mar 13, 2017 at 22:58
  • 1
    $\begingroup$ I've edited your question with the information you provided and to make it not asking specifically for an outside resource. Thanks for responding. (The goal is to create good, long-term useful answers and that means making sure that the questions don't invite bad answers.) $\endgroup$
    – Kevin Reid AG6YO
    Commented Mar 13, 2017 at 23:52
  • $\begingroup$ Back at you, corporeal - in the time it took to argue about forum quality, you could have edited some details into your question and had it reopened much quicker. It goes both ways. There's enough experience around here that people, especially moderators like @KevinReid, know what questions need to be able to get really good answers, so in the long run listening to them is likely to benefit you. $\endgroup$
    – ArtOfCode
    Commented Mar 14, 2017 at 1:39
  • $\begingroup$ I think this is a great question, but unfortunately a bit hard to fit into Q&A format though maybe refined. What sort of things would you find interesting? "Scanner listening" type stuff, listening in on AM/FM voice signals on the airband, local EMS, etc.? Or playing with digital signals, like checking out all neighborhood weather station/TPMS/garage opener chirps around 433MHz? Receiving weak/unusual signals from satellites, or HAARP (upconverted) or shortwave stuff? Throughout the rtl-sdr.com blog archives are many, many examples of things people are doing with the lower-end SDRs. $\endgroup$ Commented Mar 17, 2017 at 8:33

2 Answers 2


If you are near any airports, the AM VHF airband or aviation band (roughly between 108 and 137 MHz) is standard throughout most developed countries, and within the frequency range of most generic RTL-SDR dongles.

Another possibility, if you are near any navigable waters, is the VHF marine band, where many countries broadcast weather and/or sea conditions constantly or often. Often narrow-band FM. A web search for Canada marine radio turns up many sites, such as: http://www.offshoreblue.com/communications/vhf-ca.php

Your national government's radio licensing agency likely has a band plan for amateur radio use. Many of those amateur bands are in the VHF and higher region, in the range of an RTL-SDR.

If you have a suitable antenna with a good clear view of the sky, your RTL-SDR can often pick up satellite signals as various orbital objects pass overhead.

Many countries use VHF bands for police and fire dispatch (there are probably online scanner frequency lists for your locale in various search databases); but make sure your country's laws allow reception of such.


I agree that what is interesting is very subjective. You can listen to anything within the frequency range of your device. If another device uses radio frequency within that range you can listen to it. You may not understand it, but that is where learning starts.

In general, anything below 30MHZ will most likely be AM or SSB and above will be FM though there are several exceptions to that. You could start on the low side and work your way up scanning and trying different modes.

As you have mentioned you've already listened to to the easy services.

Every nation has a frequency coordination service usually run by the government which allocates frequencies for users within that country. The US has the FCC, and Canada has Industry Canada. That service says what power and what type of range each frequency can be used with.

Because of the shared border between the Canada and the US, we have rules about what Frequency and how much power we can use for Amateur Radio, but those rules extend to frequencies well beyond the Amateur Radio Bands.

In the United States and Canada. Radio devices have an ID listing which allow you to look the device up in the country's database. That is one place to start searching for things to listen to.

Anything that receives or communicates with a remote device uses some portion of radio spectrum all the way up through and beyond light are listed in those services. unless it uses too low a power to be regulated or uses an unregulated section of spectrum.

There are also websites dedicated to SIGnal IDentification where people share and post waveforms from their SDR's and discuss the technology surrounding the different communication processes.

As for what you find interesting your best way to find that is to Google for

"Thing you find interesting" radio frequency.

That will provide you with not only the frequency but usually some information like signal power, modulation type and expected range which can be used to listen or decode it.

I'm not sure about Canada specifically, but the UK has laws about what you can and can't listen to legally. The US does as well, but mostly limited to voice telecommunication.


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