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Are there any software defined receivers capable of receiving Regular FM broadcast band stations and displaying a waterfall of the band from 88 MHz to 107 MHz or a significant portion of that range?

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  • $\begingroup$ Not putting this as an answer, since the existing answers do a better job of keeping this from being a shopping list question. But to give some specfic examples: the HackRF has 20MSPS bandwidth and will easily tune to that range. Since these samples are I/Q pairs, it can capture 20Mhz bandwidth, i.e. the entire FM broadcast band at once! Compare e.g. to the bladeRF, which has even wider ADC conversion bandwidth, 40MSPS, but requires a transverter(upconverter) to be added for use with frequencies below 300MHz. $\endgroup$ – natevw - AF7TB Feb 29 '16 at 21:22
  • $\begingroup$ I have an SDRPlay (RSP1) receiver and combined with the latest HDSDR software on Windows 7 it performs magnificently at WFM broadcast demodulation and recording. My SDR model is actually not manufactured any more but the RSP2 is by all accounts a worthy successor. $\endgroup$ – Wossname Jan 24 '18 at 17:55
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Almost every SDR receiver is capable of receiving the FM broadcast band. The ones which can't are typically SDR transceivers designed for specific HF bands.

The harder part of your requirements is the waterfall of “the band … or a significant portion of that range”. The FM broadcast band is 20 MHz wide, and to display all of it straightforwardly requires delivering that entire bandwidth to the attached computer (I assume you are looking for that type as opposed to a single-box SDR).

When evaluating a receiver, look at the bandwidth (MHz) or sample rate (MSPS), and that tells you approximately how much you will be able to see ay once. (Approximately because there will be band-pass filters which have some rolloff at the edges.)

However, another option if you are not looking to demodulate any one station while you are displaying the wide-band waterfall, then you can use software which rapidly steps the receive frequency across the range to construct a composite image. The most well-known tool to do this is rtl_power, but I understand that it is a non-real-time tool (I could be wrong); I hear from comments that SDR# can do it real-time.

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  • $\begingroup$ Sample rate isn't necessarily a limiting factor in the total amount of bandwidth displayed in the waterfall, it will just limit the waterfall's refresh rate at very high bandwidth settings. Even the basic RTL2832u can display >20MHz of bandwidth using SDR# and the appropriate settings. Now, if you want to actually record and/or stream that entire bandwidth at once with reasonable quality, that's a bit of a different animal. It will depend both on receiver and PC specs. $\endgroup$ – Hamsterdave Feb 27 '16 at 12:53
  • $\begingroup$ @Hamsterdave It is mathematically impossible to have non-aliased bandwidth greater than sample rate. The feature you're describing might be internally frequency hopping (like rtl_power does). $\endgroup$ – Kevin Reid AG6YO Feb 27 '16 at 16:20
  • $\begingroup$ That's definitely true. My point was more that, depending on what exactly you want from the waterfall, aliasing may well be acceptable. If your intent is looking for narrow stations over a very wide chunk of spectrum in order to then focus on those stations specifically, aliasing of a fraction of a second between the lower and upper receiving bounds isn't really problematic. My initial assumption was that OP is asking for something like that, since the waterfall was his primary focus. $\endgroup$ – Hamsterdave Feb 28 '16 at 14:02
  • $\begingroup$ @Hamsterdave I'm sorry, I was too focused on the theoretical perspective to realize that frequency hopping is a potential solution to the OP's problem. I've edited my answer to cover that. (But also I think you missed what I'm referring to; you're describing artifacts at the band edge. I'm saying you can't receive e.g. 8 MHz in 2 MSPS at all usefully.) $\endgroup$ – Kevin Reid AG6YO Feb 28 '16 at 15:57
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The HackRF is a relatively inexpensive SDR that is capable of capturing the entire FM broadcast band. It costs around $300 and can sample up to 20MHz of spectrum at a time. It can tune between 1MHz all the way up to 6GHz.

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I have had good luck using a software defined radio rig that starts out using one of the European TV USB sticks. They are often sold as RTL-SDR or as DVB-T USB STICKS.

With the right software, you definitely get a waterfall display, and you can receive anything above 70-80 Mhz without any additional hardware or mods.

I use HD-SDR and the SDR# application to tune the radio and give me a waterfall video display plus audio, plus the receiver-controls. Locally Broadcast FM is so strong that even the little stubby 4 inch tall antenna that comes with the USB-Stick (RTL-SDR) will give you fine reception.

Mine has an HF upconversion board that can be switched in, that was homebrewed by my local amateur radio club, but the unmodified version will work fine with RTL-SDR software, using that board, I can tune HF and VHF. With the upconvertor, I have a more general coverage SDR solution that will tune AM broadcast bands and the Amateur HF bands.

Sample hardware: (not vouching for this amazon product, just giving you a screenshot) http://www.amazon.com/NooElec-RTL-SDR-RTL2832U-Software-Packages/dp/B008S7AVTC

Software sample: http://www.rtl-sdr.com/big-list-rtl-sdr-supported-software/

Blog post by me on the PARC Lil Pup upconvertor Plus RTL-SDR build: http://ve3wpx.blogspot.ca/2014/04/building-sdr-kit-project-lil-pup-build.html

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  • $\begingroup$ I assume you mean "above 70Mhz. It would also be worth clarifying how much of the band you can see at once with this receiver. $\endgroup$ – David Feb 27 '16 at 8:51
  • $\begingroup$ I've played with the RTL stick - the bandwidth is enough to see multiple FM stations (at least 3 adjacent stations), but not the entire band (or I haven't played with the settings enough). A nice teaching tool for visualizing how radio works. $\endgroup$ – Jon Custer Mar 2 '16 at 16:53
  • $\begingroup$ I think it's about 6 MHz fm across the whole waterfall. I am not certain if that whole area is usable/accurate but the center 2-3 MHz is certainly quite clear and accurate. $\endgroup$ – Warren VE3WPX Mar 2 '16 at 18:17

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