good sdr to catch most of the shortwave pirate spectrum?

[tech53]

Hey just curious if anyone has suggestions. I have the airspy hf + discovery but don't even get a mhz. How is the SDRPlay? I see it gets 10mhz, but i worry it would let too much in...plus the bit depth is significantly lower. Maybe just another airspy? I dunno. I often find myself wanting to tune 2 different portions of the spectrum.

[ChrisSmolinski]

One option would be a KiwiSDR, you can have four full receivers running at the same time in different browser tabs, each over any portion of the HF spectrum and with demodulation on one frequency each.  You can't record I/Q files however.

Two Airspy's is a good solution as well, you can run multiple instances of SDR Sharp, I do that occasionally.

What are your exact requirements?

[bagmouse7]

The Elad S3 will do 24 Mhz and the RX888 will do 32 MHz.
Using SDR console will let you define multiple receivers across the received band with these receivers.

[Charlie_Dont_Surf]

you can run multiple instances of SDR Sharp, I do that occasionally.

I think that you know this already but for others' benefit, related to that, SDR Sharp will allow you to run what amounts to a second receiver, that they call a "slice", at the same time as the first.

As long as the "slice" is tuned to a frequency within the main receiver's bandwidth, and presumably the slice's bandwidth does not extend outside it either, you can have what amounts to a second receiver. This is a bit like a second VFO but the difference is that you are receiving both at the same time instead of having to switch between the two. Of course, since the HF Discovery+'s bandwidth is limited to something like 500 KHz (I forget), you can't be listening to, say, 11 meters and a pirate on 43 meters at the same time. That's where you would need a second receiver.

I don't even know if there is a software-defined limit to how many "slices" can be running at once, so you might be able to run more slices than just one.  However, I'm sure that there a practical limit, as "slicing" takes up processor time and USB bandwidth. Eventually things will start to slow down and you will start to notice gaps in audio, etc.

[Synclair]

Hey just curious if anyone has suggestions. I have the airspy hf + discovery but don't even get a mhz. How is the SDRPlay? I see it gets 10mhz, but i worry it would let too much in...plus the bit depth is significantly lower. Maybe just another airspy? I dunno. I often find myself wanting to tune 2 different portions of the spectrum.

I just noticed this thread, so sorry for late response.

Since you ask about the SDRPlay, I use a SDRPay RSPdx and find it to be a very good receiver, assuming you have a decent antenna. It can display and record up to 10 Mhz slice of the band - more than enough to cover a single band - and covers all of the HF bands with no gaps - 1kHz-2Ghz. By using it with SDRUno, it serves me very well for reception. I also use it with SDR Console 3, with which I can record up to 10 MHz slice of the band and play it back later to find anything I've missed.

The dx SDRs have three antenna inputs - two sma for the full range and one BNC for frequencies up to 200Mhz. They are also have design improvements for use at frequencies below 2MHz. This makes them very useful for MW DXing.

If you want to tune 2 different portions of the spectrum, you could consider the SRDPlay Duo - it is essentially two tuners in one.

More on their range of SDRs here: https://www.sdrplay.com/products/