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Author Topic: First SDR receiver  (Read 437 times)

Offline IZS4

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First SDR receiver
« on: February 08, 2020, 0108 UTC »
About to get my first SDR receiver (RSP2) .Im very excited. I currently have a 135' OCF dipole positioned East/West and plan to have another dipole type antenna for North/South. Tomorrow I'm expecting a discone for UHF/VHF to arrive. From there some type of loop. Going to take a break from Ham radio to learn the ins and outs of the equipment. It will also be very helpful for the TX side of things also. I've been reading up on SDRuno and should be off to a good start. If you have any solid advice for an SDR newbie, please feel free to post. Thanks
Listening on an Icom-718 with a 135' OCF dipole or a RSP2.  Grundig G3 and MLA-30 when portable. When QRP I use a Hendricks PFR-3 I built. Coverage is 20,30 and 40 meters.

Offline NJQA

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Re: First SDR receiver
« Reply #1 on: February 08, 2020, 1053 UTC »
The RSP2 is a good SDR.

One thing to keep in mind about it (and most any SDR) is that if a strong signal is present at the input, you may see weird artifacts at other frequencies.  If you have a strong local AM, FM, TV, LMR, etc station nearby, you may need an additional filter.  The RSP2 has filtering built in, but some locations require a little more.  Fortunately, inexpensive filters are available.  Try it out and see if it this is needed.

Along the same lines, SDRuno has a lot of adjustments to tweak.  If performance doesn’t seem very good, it is more likely that some SW parameter needs adjusting rather than the RSP2 being broken.


Offline IZS4

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Re: First SDR receiver
« Reply #2 on: February 08, 2020, 1259 UTC »
Thank you. This is just the type of advice I'm looking for. Luckily for me I don't have any large transmitters near me.
Listening on an Icom-718 with a 135' OCF dipole or a RSP2.  Grundig G3 and MLA-30 when portable. When QRP I use a Hendricks PFR-3 I built. Coverage is 20,30 and 40 meters.

Offline IZS4

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Re: First SDR receiver
« Reply #3 on: February 08, 2020, 1311 UTC »
I know that one thing I will need to learn is how to interpret the waterfall in regards to the signal being AM,SSB, digital etc. The onl worry I have is that I stare at my computer a lot of the day at work and now I'll be staring at a computer for hours when I get home. I'm going to have to come up with an explanation for management at work, as to why I'm no longer using the computer in my office!
Listening on an Icom-718 with a 135' OCF dipole or a RSP2.  Grundig G3 and MLA-30 when portable. When QRP I use a Hendricks PFR-3 I built. Coverage is 20,30 and 40 meters.

Offline NJQA

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Re: First SDR receiver
« Reply #4 on: February 09, 2020, 1237 UTC »
The waterfall is a game changer.

A long time ago I had a Heathkit HO-13 spectrum display connected to my SB-303. This only showed the real time spectrum maybe +/- 50 kHz of what you were tuned to.  It was interesting, but not terribly useful and I soon traded it for something else.

Fast forward a few decades to the era of DSP radios with not only real time spectrum display, but the waterfall that allows you to see things that happened seconds or minutes ago.  Now you are seeing signals that you would have missed in the past - either because you weren’t tuned to that frequency or they were too short in duration.  You are also realizing that something you had dismissed as RFI was in fact a wide band data signal - because you can now see the entire spectrum of the signal.

DXing without a waterfall is like driving while wearing horse “blinders”.  You won’t go back.

There is only so much you can do as far as being to recognize modulation types off of the waterfall.  CW, RTTY, AM, or SSB are pretty easy, but the digital modes are another matter.  This makes sense when you realize that fundamentally many digital modulation schemes are similar.  For instance COFDM is used in many waveforms - but the number of sub carriers and the spacing might be different.  On your waterfall they will look similar.  There are programs available in the commercial market that will perform signal modulation identification but the pricing is way beyond what most of us can afford.

I saw a posting recently by Josh where someone had written something to try to do this.  I have no idea whether it works or not.

https://www.rtl-sdr.com/shazam-style-automatic-signal-identification-via-the-sigidwiki-database/
« Last Edit: February 09, 2020, 1245 UTC by NJQA »

Offline nickcarr3151

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Re: First SDR receiver
« Reply #5 on: February 09, 2020, 1448 UTC »
I bought the RSP2 when it first came out.  Honestly I wasn't that impressed.  The software was the deal-breaker for me.  I think for people who haven't really played with SDRs before it looks fabulous but for those of us who have had SDRs before it's hit or miss.  It probably comes down to what we started with and what we get used to over time.

I will admit that for the price, the RSP2 is a pretty good deal but that software... ugh.

It's starting to change now that SDRs are becoming more wideband but yes, I think I'm happy to have a SDR for HF and others for higher frequencies.  The latter requires a NOAA + FM notch filter for me.  Also I find myself using filters for specific frequency bands.  This lets me crank up the gain on the SDR without any intermod.
Perseus SDR + Wellbrook ALA100LN (60m loop), Wellbrook 1530S+
ICOM 7000 + Zero-Five 10/40 GP Vertical
Xiegu G90
Motorola XPR/XTS Portables, Uniden scanners, Whistler Scanners
Airspy Mini SDR + DSDPlus + Diamond D3000N Discone

Offline IZS4

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Re: First SDR receiver
« Reply #6 on: February 09, 2020, 1537 UTC »
When you say software, are you talking about the SDRuno or another aspect? That my seem like a silly question because I'm a newbie to SDR. I've been watching a lot of videos to help prepare and I printed out a review that Josh had done some time back. I plan on reading that today along with the basic manual. I think it will keep me happy and busy learning for a good amount of time. Thank you for the feedback.
Listening on an Icom-718 with a 135' OCF dipole or a RSP2.  Grundig G3 and MLA-30 when portable. When QRP I use a Hendricks PFR-3 I built. Coverage is 20,30 and 40 meters.

Offline nickcarr3151

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Re: First SDR receiver
« Reply #7 on: February 09, 2020, 1545 UTC »
Yes the SDRUno software is what I was referring to.  It also can be used with HDSDR which is OK but it's still kind of meh to me.  I was spoiled early on.  I really haven't seen anything that would make me switch from my Perseus SDR.
Perseus SDR + Wellbrook ALA100LN (60m loop), Wellbrook 1530S+
ICOM 7000 + Zero-Five 10/40 GP Vertical
Xiegu G90
Motorola XPR/XTS Portables, Uniden scanners, Whistler Scanners
Airspy Mini SDR + DSDPlus + Diamond D3000N Discone

Offline IZS4

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Re: First SDR receiver
« Reply #8 on: February 09, 2020, 1605 UTC »
I'm assuming the Perseus has it own platform. What would be your preference over the SDRuno in regards to non Perseus software? I'm not familiar with any others.
Listening on an Icom-718 with a 135' OCF dipole or a RSP2.  Grundig G3 and MLA-30 when portable. When QRP I use a Hendricks PFR-3 I built. Coverage is 20,30 and 40 meters.

Offline nickcarr3151

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Re: First SDR receiver
« Reply #9 on: February 10, 2020, 0010 UTC »
Yes Perseus has it's own proprietary software written for it.  The author came out with a 2.0 update a few years ago and it's plenty good enough for me.  The Perseus also has it's own network so users can host their units online and other users can remote into that Perseus.  These are all over the world.  It's not perfect but it works fairly well.

The problem with XYZ SDR is that most don't want to be open source -- or open to others using their hardware.  RSP2 only allows HDSDR support -- at least it did when I owned one.  It didn't allow for 3rd party software support.

I still break them down into HF vs VHF/UHF since that's how they started. 

If you go here and look at the top shortwave receivers then you'll see the Perseus still very near the top of the list:  http://www.sherweng.com/table.html

This table is trying to show which receivers have the best chance at pulling out weak signals and/or the ability to distinguish two valid signals very close to each other.

I haven't used all of the SDRs out there so it's hard for me to say which is best.  With the RSP2 you'll be limited to whatever software they support. 

Give it a chance and see how you like it. 



Perseus SDR + Wellbrook ALA100LN (60m loop), Wellbrook 1530S+
ICOM 7000 + Zero-Five 10/40 GP Vertical
Xiegu G90
Motorola XPR/XTS Portables, Uniden scanners, Whistler Scanners
Airspy Mini SDR + DSDPlus + Diamond D3000N Discone

Offline Josh

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Re: First SDR receiver
« Reply #10 on: February 10, 2020, 0203 UTC »
For an rsp2, sdrconsole and hdsdr are my faves, but sdruno has very nice audio and agc but at a much higher cpu and mem footprint than the others. Hdsdr is the king for low cpu time.
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Offline nickcarr3151

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Re: First SDR receiver
« Reply #11 on: February 10, 2020, 1940 UTC »
Yeah I tried SDRConsole with my Perseus just after v3 came out and it wasn't that great.  The UI is pretty but it seemed a bit wonky from a functional stand-point.  I haven't used it since so it may have been updated by now.

Good to see that they added RSP-family support.  It wasn't available when I purchased the RSP2.
Perseus SDR + Wellbrook ALA100LN (60m loop), Wellbrook 1530S+
ICOM 7000 + Zero-Five 10/40 GP Vertical
Xiegu G90
Motorola XPR/XTS Portables, Uniden scanners, Whistler Scanners
Airspy Mini SDR + DSDPlus + Diamond D3000N Discone