OpenWebRX+ on Pi 400 and LAN

[dkcorlfla]

Hi all, I had a Raspberry Pi 400 laying around doing nothing so I thought it would be fun to try and setup OpenWebRX + on it and see how well it might work on the LAN

As it turn out it works great, the Pi 400 is not even close to being tapped out. I'm using the slower 2.4 Wifi and it's able to play WFM no issues.

Makes me think OpenWebRX+ may run on a Raspberry 3B+

Maybe the next thing to try is mounting the 3B+ outside close to the antenna for some low loss UHF and up fun.

 

[vagrant]

I run OWRX+ on a Pi 4 w/4GB of RAM connected via Ethernet. I turned off the WiFi to reduce power and heat. I am finding out that OWRX+ does not perform well, or at all, with lower sample rates. It will error out and fail over to a second SDR. My current testing is with an RTL-SDR v3 for VHF/UHF and a v4 that handles HF. They each have higher and different serial numbers. I even tested the HF end with another v3 dongle, so the issue is not my specific v4, but my lack of working within the RTL-SDR hardware limitations.

With lower rates the Pi enjoys less of a hit on the CPU, but starving the sample rate has its own problems. I am simply finding out what many others have before me. While I would prefer to offer smaller snapshots of the spectrum down in HF, the hardware is not having it.

Juxtaposed to HF is VHF/UHF which has more bandwidth and the RTL-SDR dongles are limited to mostly 2 Msps. Thus, more than one profile would be needed to cover a band. Now is the time to experiment using my SDRPlay RSP2 instead.

Getting to your question dkcorlfla of using a Pi 3, I think it will work for a single user while using known sample rates the RTL-SDR dongle versions support. Had I initially tried this on a Pi 3B, I would have wondered if the Pi was at fault.

The FUN part is the variety of modes OWRX+ supports with the decoders as well as scheduling and storing data. Of course the remote access is the favorite. With the variety of antennas I have along with a diplexer, I can really get the best out of it. ( I still use scanners to handle Mil Air and many other things )

* For those that are curious, my Pi 4 is supplied with 3.6 amps. I do not recommend less when directly using dongles. I also use 15cm long USB M/F pigtails. This reduces the heat on the Pi by not plugging in a dongle directly. Yes, I use a fan on the Pi heatsinks as well. Forget that passive cooling shenanigans for stuff like this. Keeping a Pi below 40 degrees Celsius has worked well for years.

 

[vagrant]

Over the last 24 hours of receiving a Pi 4 along with configuring and playing with OWRX+, the SDRplay device affords more granular control. While the SDRplay RSP2 is obviously an improved device over an RTL-SDR, it really becomes clear using OWRX with various profiles in different bands. Still, I have the RTL-SDR dongles so I will offload stuff like ADS-B, NOAA, APRS, POCSAG, ISM and other single or several close frequency selections like FM and AM broadcast to the RTL-SDR v3. The benefit of the RTL-SDR is a slightly reduced hit to the CPU.

The bookmarks feature is nice as well. I expected I would need to edit configuration files via a shell, but even adding the bookmarks are web based. ( Not the web browser bookmarks you may be thinking of ) I don't know why I didn't come across this software years ago, but I am benefiting from it being forked along with a revision history of trial and errors resolved.

The most inexpensive route for OpenWebRX+ would probably be a Pi 3B along with an RTL-SDR dongle. The preferred route is a Raspberry Pi 4 w/4GB of RAM or more along with an SDRplay device. Even if the SDR has a single port, one could use a diplexer or triplexer depending on antennas intended for use.

Right now, the only thing that gets in the way of my SWL/scanner hobby is my other hobby of transmitting. Fortunately, HP/Agilent limiters and switches keep things friendly along with filters...many filters to squash QRM not my own.

Time to add some profiles for this device as this thing can decode various modes along with packet, FT8, NAVTEX, ACARS, etc.

 

[dkcorlfla]

View attachment 182152Over the last 24 hours of receiving a Pi 4 along with configuring and playing with OWRX+, the SDRplay device affords more granular control. While the SDRplay RSP2 is obviously an improved device over an RTL-SDR, it really becomes clear using OWRX with various profiles in different bands. Still, I have the RTL-SDR dongles so I will offload stuff like ADS-B, NOAA, APRS, POCSAG, ISM and other single or several close frequency selections like FM and AM broadcast to the RTL-SDR v3. The benefit of the RTL-SDR is a slightly reduced hit to the CPU.

The bookmarks feature is nice as well. I expected I would need to edit configuration files via a shell, but even adding the bookmarks are web based. ( Not the web browser bookmarks you may be thinking of ) I don't know why I didn't come across this software years ago, but I am benefiting from it being forked along with a revision history of trial and errors resolved.

The most inexpensive route for OpenWebRX+ would probably be a Pi 3B along with an RTL-SDR dongle. The preferred route is a Raspberry Pi 4 w/4GB of RAM or more along with an SDRplay device. Even if the SDR has a single port, one could use a diplexer or triplexer depending on antennas intended for use.

Right now, the only thing that gets in the way of my SWL/scanner hobby is my other hobby of transmitting. Fortunately, HP/Agilent limiters and switches keep things friendly along with filters...many filters to squash QRM not my own.

Time to add some profiles for this device as this thing can decode various modes along with packet, FT8, NAVTEX, ACARS, etc.
View attachment 182153

Curious on what it took to get the SDRplay to play on the Linux based Pi? SDRplay API? Connect? Something else?

Thanks

 

[vagrant]

I downloaded and used the pre-built Raspberry Pi image, in particular the 64bit. After installation I noted that it was already setup for three different dongles. The RTL-SDR, AirSpy and SDRplay devices. Each of them already had various profiles as well. I expected to jump through more hoops, but they worked right away. I simply plugged in the devices. Well, I did need to give the RTL-SDR devices new serial numbers. I used 00000088 and 000000160. I should have read through the instructions, but I just pushed through and figured it out later.

Although I initially tested the SDRplay, I deleted the device from the list along with the Air Spy. I planned on only using the RTL-SDR v3 for VHF/UHF and v4 to handle HF. I later simply re-added the SDRplay device yesterday. I have created over two dozen profiles and deleted them during testing when removing devices. These devices have their own particulars when creating profiles and then my own needs in addition to that.

The one thing I found in my testing is not to use any gain. It made things worse. I have outdoor antennas and removed that gain option from the profiles. What is taking time is adding bookmarks for each profile. I’m backing certain things up as I go. I’m in no mood to redo those bookmarks again, plus I can import them later into another Pi.

I’m having fun operating it from my desk, but using one my iPads or a tablet is supreme. The benefit of my outdoor antennas with various filters inline beats using a handheld receiver like my Icom R30 and a compromised antenna attached to it.

OpenWebRX+ Home Page

 

[KC1UA]

I've been using this with an SDRPlay RSPDx for the last few months and it is an amazing piece of software. The gain settings with the SDRPlay devices appear to require an immense amount of tweaking but worth the effort IMHO.

The one thing I will caution on is there does not appear to be a way to backup the profiles you create. The documentation does indicate where certain files are for backup, but it does not seem that this includes the profiles. Further commentary in the Openwebrx message group at Groups IO seems to indicate that there's been a request for this but it has not been implemented. It seems feature requests are occasionally met with grumpiness and a few times outright hostility, unfortunately.

It is certainly worthwhile to try to get set up if you have a Pi laying around. I am using a Pi 4B with 8GB of RAM and a 64GB SD and used the pre-burned image as well. I found out profiles don't seem to be recoverable when I tried to move to a more robust drive (64GB Samsung USB drive) so for now I've stuck with the SD card which should be okay until I look at it the wrong way and it fails....

It should be noted that I know enough about Linux systems to get myself in trouble, but with that in consideration the installation of this was pretty easy to get going.

 

[vagrant]

I’m sure I can find the paths for the profiles and bookmarks. I will then post the shell command to simply zip that data to your home directory. You can then just copy the zipped file over to a thumb drive, or use FTP or Samba. If you have the desktop running on your Pi it is even easier. I run headless and use a shell. I don’t think the desktop is running for that Pi image in order to keep processing low.

I won’t have time until after noon Pacific time tomorrow due to work/sleep/life. Check back here after then and you should be good. Not many people are familiar with Unix, so I can see the issue. Still, I can also understand them not being in the mood to create some web based interface to do that. I prefer they focus on OpenWebRX myself. Unix commands are pretty simple.

 

[vagrant]

Okay, just got home and took a look around. I'm going to provide two methods. First is GUI using a desktop on the Pi or a Real VNC viewer if remote. The second method is via a shell. If you goof this up, it's all on you. If I am wrong, it's all on you. I'm some guy on the Internet. All this will do is backup "your" custom configurations like bookmarks, profiles, avatar. If you are uncomfortable with either of these methods, FULL STOP. Read this through before you begin.

GUI
( This presumes you are running a desktop on your Pi. This may be the easiest and most familiar method for many. )
1. Plug in your USB thumb drive, or whatever kind of drive into an available USB port on the Pi.
2. Open the File Manager window and navigate to /var/lib/openwebrx/
a. You will see various files. Hold down the Shift key and click on each of the files "except" users.json. Now keeping your mouse cursor over one of the selected files "right click" and choose "compress". This will open another window.
b. In this new window where it says Name: at the top delete what is in that field and type "openwebrxbackup". You can name this whatever you want, or name it something like owrx20250422 if you want to create and retain progressive backups.
c. At the bottom left of that File Manager window where it says Archive Type: choose "Zip" in that option window.
d. Now select/click on your USB thumb drive on the left side of the File Manager window.
e. Now click the "Create" button at the bottom right. At this point you will have created a compressed backup of your profiles, bookmarks and other important custom configurations onto your thumb drive. You can select your thumb drive on the left of the File Manager window to see the files and confirm it is in there. Huzzah! You're done. If you unzip it you will see a folder named "var". Inside of that is "lib". Inside of that is openwbrx and inside of that folder are your files.

Shell
( All command prompt here. No mounting thumb drive shenanigans either. Read this through first, then start at #1 )
1. After you login, from the command prompt type the following: zip -r owrxbackup.zip /var/lib/openwebrx/
a. You will see various text scroll across your screen and even see a warning/Permission denied. Don't worry, that's fine. The zip file you create will probably be under one Megabyte as most of it are text files, so it will compress the files down. You will now have a file in your home directory labeled owrxbackup.zip Alternatively, you could name it something else, but perhaps avoid that at this point.
b. Now type: sudo mv owrxbackup.zip /usr/lib/python3/dist-packages/htdocs/
*c. Now open your web browser and type the following into the URL window: openwebrx.local/static/owrxbackup.zip
d. You may now be prompted to allow downloading of the owrxbackup.zip file to your computer. Click yes, or allow.
e. Boom! The backup file is now on your computer huzzah!

* At point c, you may need to type in the IP address of your Pi instead of openwebrx.local. Simply use whatever you have been doing to open and use it, but add the /static/owrxbackup.zip immediately after. (e.g. 192.168.1.55/static/owrxbackup.zip )

All of those slashes / / are important! Even the one's at the end for this shell method!

* * Note: Mac OS users, inside your Downloads folder your won't see the zip file. Your Mac will open the zip file and you will see a folder in Downloads named "var". Inside that folder is "lib". Inside that folder is openwebrx and inside of that folder are the custom configurations, bookmarks, images, etc.

For those doing the shell method, when you want to create a newer backup, just follow what I noted above. When you perform the move command "mv" at step b, it will overwrite the earlier file. If you are prompted to overwrite the file, choose Yes. This will avoid multiple backups stored on your Raspberry Pi MicroSD card by using the same name. You can rename it once it's on your thumb drive, if you want to create progressive backups.

 

[vagrant]

Curious on what it took to get the SDRplay to play on the Linux based Pi? SDRplay API? Connect? Something else?

Thanks

While digging around I saw a folder named SDRplay_API, or something like that. I forgot where, but just an FYI. That was part of the image and not something I added later.

 

[dkcorlfla]

While digging around I saw a folder named SDRplay_API, or something like that. I forgot where, but just an FYI. That was part of the image and not something I added later.

Thanks, I will be looking into this as I have also have Allstarlink 3 running on the P400 and don't really want to use the image.

I also have Debian 12 available in a KVM and was trying to figure out how to use the SDRplay on that system too.