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Help Me Select An SDR

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#1
I have been toying with the idea of getting an SDR. Ideally, it would be one that will properly decode LSM/CQPSK transmissions. Which, if any currently available will do that? And, if there are more than one available that will do that, which will decode multiple digital formats? I would love to have a receiver that would receive a given frequency, properly decode it, and also display any other data like PL/DPL/NAC Code/CC/TS/TG ID, etc.
 
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#6
I think people don't seem to understand that SDR means Software Defined Radio so, in essence the hardware aspect is just a radio tuner like any other - it's the actual software that makes the difference, that handles the formats/protocols/etc and does the decoding of said formats/protocols/etc. I suppose one could argue that a true hardware device is still just running hardcoded software not really meant for easy alteration aka firmware and that using such a device with software running on a computer is a different beast altogether that allows for (potentially) more capabilities to be put into action as long as the software provides that kind of functionality.

While those monstrously expensive devices at that one hardware manufacturer are pretty neat I suppose, I'd rather have something a lot less expensive and (potentially) just as capable given talented developers writing awesome software applications that take advantage of the "cheap USB TV tuners" so many of us now use as well as the better hardware like Airspy/SDRplay/HackRF/etc.

Always something going on. ;)
 

Token

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#8
I have been toying with the idea of getting an SDR. Ideally, it would be one that will properly decode LSM/CQPSK transmissions. Which, if any currently available will do that? And, if there are more than one available that will do that, which will decode multiple digital formats? I would love to have a receiver that would receive a given frequency, properly decode it, and also display any other data like PL/DPL/NAC Code/CC/TS/TG ID, etc.
Just as br0adband said, the software is what you are asking about, not the hardware.

The features you are asking for are the result of the software running the SDR, and not tied to any specific SDR hardware. Assuming the SDR will receive the correct frequency range it is the software, the GUI, that will determine what modes can be demodulated/decoded.

From the information you requested it looks like anything from the very cheapest SDR RTL Dongle to the latest wiz-bang wideband SDR will do what you ask, as long as it receives the right frequency range and you can find a software suite that does what you want.

As for the R&S link, sure, you can find it there, for the cost of a nice car on up. By the time all the hardware and software options got added up on the new R&S FSW26 at work it came out to $240k, and it will do everything you asked for ;) The $13 to $30 RTL SDR option might be the better route for you though.

T!
 
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#9
While I agree it works well I find the "NooElec NESDR SMArt " to be superior. The usb connector on the "RTL-SDR Blog" one seems to get fatigued fairly quickly, as one of the reviews on amazon has said. Mine now likes to drop connection if there is any movement in the usb. the "NESDR SMart does not seem to have this issue. They are both based on the R820T2, but with slight differences that I wont get too into. just my $.02.
 
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#10
With any of the SDR sticks, a short USB extension cable is a good idea. It reduces bending force on the USB plug on the stick and the jack in the computer if the stick gets bumped while plugged in.
 
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#11
With any of the SDR sticks, a short USB extension cable is a good idea. It reduces bending force on the USB plug on the stick and the jack in the computer if the stick gets bumped while plugged in.
Agreed though i would say the longer the better to a certain point, i have a active usb extention on mine that is 32ft long so i can locate the sdr quite far away from the computer and other noise sources.We are in the process of moving and when we do I plan on putting a dual band antenna(17 ft) on top of the barn with a remote computer to control the sdr so i get low noise floor and maximum signal.

something to remember is you must get your sdr in a area with minmal "noise" and the antenna that comes with some of them aren't that great but are usable.
 

Your_account

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#12
More important are the Filter. When I compared the Messages I received with and whitout the Dongle with wins.

The other problem with (cheap) SDR the could be fast overload.
 

wakker200

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#13
I just started looking into this a month ago.

For starters I have a RTL-SDR dongle (the one you can find on Amazon) plugged into a Raspi 3 running OpenWebRX on Raspbian. It "works". It was relatively easy to get this up and running.

The ease of use and performance of this setup makes it ok for testing but not cool for SWL, which is my intended use. The tunable range is hard coded into the application, and is very small for this dongle. In order to change the "dial" I have to ssh into the server, edit a line in a python file, and then restart the server.

I am still evaluating hardware. Some of the manufacturers have software designed for their hardware. There is some software that is friendly to more than one piece.

If anyone has direct experience with a SDR on their LAN for SWL, please advise.

Below is a link to a list of hardware that might be useful. Not found on the list is Kiwi, which is definitely found on the web.

Roundup of Software Defined Radios - rtl-sdr.com
 
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