The official blog of the Hudson Valley Digital Network
Here is the jump to my replay of the "Top Ten: Democratic Open-Source Software Defined Radio and Amateur Radio Applications That Matter Today" presentation on Saturday.
https://youtu.be/bEatax_cbKA?
Other related stuff here https://hvdn.org/hope16.html
It has been a while since an article has posted here, so this should be a good one involving a controversial SDR plus some 3D printing tips related to designing a simple enclosure for it.
Quick Summary: Saving you a 20 minute video
Why is everything about price? For usually under $30, this SDR can be purchased on a few websites like Aliexpress and I am NOT encouraging you to buy this. Why? It has infringed on the intellectual property of SDRplay in some regards. The driver used to get this and other similar MSI2500 chip based devices to work not made by SDRplay is needed.
Only until recent versions of the driver, cloned versions of the RSP1 could use the driver to work with software easily like SDRangel, but that stopped after SDRplay API version 3.7. I am glad that SDRplay built in some functions to only allow genuine SDRplay products to work with some of its software.
However, since reference designs have been made public on the SDRplay earlier devices, anyone can freely assemble different semiconductors to replicate a decent SDR. The device shown in the video uses separate band pass filters which is actually nice so the user can have spectrum specific antennae in use without the extra noise or complexity of electronic switching or the need for software to control that. This is why the SDR is so inexpensive.
Now that enough time has passed since I purchased these "clone" SDR devices and there are some improvements to protect SDRplay in place, now is a great time to get back to this.
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| https://www.aliexpress.us/item/3256805375754709.html |
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| https://www.aliexpress.us/item/3256804660151348.html |
Here is the 2021 video talking about getting the SDRplay API to allow an SDRplay. Please note that this will not work any longer due to changes made by SDRplay, but there is an alternative version available called libmirisdr you can search for on your own or until I make a video about that.
Would you like the STL or OBJ or 3MF or STEP files for my case design? Please leave some nice and friendly comments in the video called Controversial SDR: Plus 3-D Printing Stuff and will see what happens next. :)
Life has been busy for Steve K2GOG and that is reflected in the lack of recent blog entries on HVDN Notebook. This post "should" have happened in late May or early June, but that was not possible due to 1,000 other distractions such as our Hudson River Radio Relay on June 11th, ARRL Field Day on June 25/26, a new job, countless family adventures and other stuff..
However, lets get things back on track here since it has now been five years since HVDN began and this is an appropriate way to re-energize with HVDN readers via our twice a year global digital repeater roundup series. Look for more stuff coming soon plus BIG news regarding HVDN if you live in the Hudson Valley of New York.
First off, let me apologize for having to use July 10th 2022 data to provide the 1H22 reporting data.
This extra month plus a few extra days should not really throw anything too far off, since its still clear that the total global digital repeater mode leader in volume is DMR. However, P25 is the true leader if we look at overall CAGR.
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As noted in the table above, data is shown from May of 2018 and through July of 2022. Measurements are taken every end of May and end of October. Raw data per mode is shown for each period and CAGR was calculated for the May and October periods independently. An average of both periods can be found at the far right of the table.
The below table shows the included 2016 data if you were wondering how long we have been tracking things if you are a new reader and missed the past nine other articles.
Report: What has happened in digital voice since October 2021?
Well this is rather interesting to say the least. In our October 2021 edition, I predicted some growth projections as found in "SPECIAL EDITION: 10,000+ Digital Repeaters - October 2021 Global Digital Repeater Roundup" and I was not "too" wrong.
Estimates I predicted last October for May of 2022 included:
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| Yaesu FTM-200DR pictured which retails for around $380 USD and is competitive against other digital mode offerings for competition modes |
Oh, sad sad Icom. Will you figure things out when it comes to D-Star? To your credit, I was surprised just a little as I had expected that you would lose repeaters according to repeaterbook.com but you did actually gain a few.
Now I am not sure if all 2471 around the world are actually active and if repeaterbook.com removes incorrect data as frequently as they should. I do know that when traveling not every D-Star repeater is on the air though....so your secret is safe with me for now.
Maybe people who now have the super fun Icom IC-705 and IC-9700 have put pressure on magical repeater gnomes to conjure up a few more repeaters to use those expensive radios on or the new handheld ID-52 which finally is shipping. Maybe this is true, but CAGR still does not lie.
Hovering around 1% CAGR is not fun to see, but perhaps if some cost effective equipment that supports D-Star ever comes to market, that should change things like we see with Fusion and DMR.
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| Be honest, did you buy a $1700+ Icom IC-9700 radio to talk on your local repeater? If yes, I would love to hear about that |
Ok, now for the record, I currently own more D-Star capable radios than I do for DMR. However, DMR is the mode I use the most still when I have time to play radio.
The Alinco DJ-MD5XTG continues to be my favorite "ham" grade DMR radio and I sort of wish something more expensive and with features like the D-Star Kenwood TH-D74 or Yaesu FT-5DR would come to market. The RFinder B1 is a really cool radio which supports DMR but I am not interested in a smartphone based device for $1000 USD.
With continued impressive repeater growth numbers for DMR, most people probably are using Anytone or Alinco equipment plus who ever is still supporting TYT and Radioddity based equipment. The key thing here is that lower cost gear gave DMR a boost and repeater ninjas knew what to invest in.
For DMR, there is even a rather good Under $30 basic radio called the COTRE CO01D which only can program 16 channels, but otherwise is great to use with a hotspot on limited talk groups. It is doubtful we will ever see a competing D-Star option at this price since the JARL license for D-Star is 2-3x the cost of just one of these radios.
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| Alinco offers the MD520 which offers dual band 2m/70cm plus 220 MHz and VHF air receive. Anytone has a comparable D578UVIII for sale at around the same price. Both compete with the Fusion radios for close to the same price. |
I was really close to my P25 prediction and was only off by 1. That is actually pretty nice.. Growth of P25 is fueled by surplus commercial equipment. NXDN is pretty much the same story and actual versus predicted growth from October 2021 to today Not much really to talk about for equipment since options for new gear are from commercial companies only and surplus options are too varied to discuss.
The growth of P25 is interesting to continue to see though. As more municipalities change radio systems around, it should be interesting to see how P25 and NXDN evolve within amateur radio.
M17: Will it happen ever?
Being nice here, but I own 3 total M17 T-shirts, a bunch of stickers and a semi-functional TYT MD-380 converted to be used via hotspot for this open source FDMA based mode. I have yet to find people local to me to try simplex M17 to M17 but have done that at a hamfest.
Every day that goes by possibly gets us closer to off the shelf turn key equipment for M17 and I am hopeful that this mode explodes once it has some reliable equipment to support it. The back end infrastructure to connect repeaters to is already in place and a few "test" repeaters are sort of available to a few people.
To help keep M17 top of mind, presentations can be found all over the place and the upcoming HOPE conference will feature at least two of them talking about this open source mode.
Feel free to check out open source RF experimentation at 10:00 AM Saturday July 23rd co-presented by Steve K2GOG and Joe NE2Z plus a much more legit one about M17 scheduled along with so many great ones found at https://scheduler.hope.net/new-hope/schedule/#
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| HOPE 2022 is going to be epic and hope you can make it in person or virtually |
Do you have a Raspberry Pi 4 that needs a new use? Have you wanted to run your RTL-SDR V3, HackRF, Lime SDR or other SDR on something other than a dedicated computer? Are you afraid of the word "dependency" when it comes time to compile applications on Linux? Would you like to be able to better sense the RF world around you?
If you answered yes to any of those questions, SIGpi is going to be worth paying attention to. What Joe Cupano NE2Z has done is created a set of automated installation scripts and menu system to allow for easy automated installation of many popular software defined radio applications and optimized a few things to run on Raspberry OS 64-bit (or 32-bit) systems.
Quick Dare To Compare
Dragon OS is a precompiled Linux operating environment along with many popular SDR and related applications which is quicker to get started with compared to SIGpi.
The major benefit with SIGpi is user customization for what you wish to install as the main applications. And, when it comes to to update applications like SDRangel or SDR++ as example, a script called "pusher" allows the prior version to get updated to the latest version without breaking dependencies.
Beyond many of the visual applications that may be of interest to those interested in "signal interception" work, many command line and other applications of interest to wireless network or amateur radio professionals are also included.
These are some of the user experience driven benefits of what makes SIGpi unique and beneficial to different users and for those with different levels of technical abilities.
Pre-Education: Getting Started with SIGpi
Go ahead and grab your favorite SDR device which is NOT one of the SDRplay devices and install a fresh copy of either the 32 or 64 bit version of Raspberry OS onto a new 32GB or larger SD card.
A few quick notes:
Once you have your fresh SD card ready with Raspberry OS version of choice, it would be a good idea to enable SSH support for later ease of access.
Enabling SSH access on a Raspberry Pi likely is something our readers should be aware of already.
After you log in to your Raspberry Pi for the first time with the generic credentials, it may also be a good idea to sudo raspi-config and also enable VNC support for further headless access.
SIGpi has intentionally turned off Wi-Fi interface, so you can also choose to turn that back on if you like while you are in raspi-config when connected over LAN.
A Few Easy Steps
There are only a few steps you need to do now that you have your Raspberry Pi 4 that is hopefully connected to the internet now to now move towards getting SIGpi installed and you have already completed the usual apt-get update and apt-get upgrade sequences.
Below in green are the commands needed via terminal to get ready for SIGpi. Details are also in the Git repository page here.
First, you will need to run sudo apt-get install -y build-essential cmake git . This will add some other important pieces to your stock Raspberry OS installation.
Next,, you will need to mkdir ~/SIG && cd ~/SIG in order to create the directory where SIGpi will end up and also automatically move you into that directory for our next step.
Use this opportunity now, if not already, to make your terminal screen full screen on your computer which will be helpful for some later steps.
The third thing to run via your terminal is:
git clone https://github.com/joecupano/SIGpi.git
This important step will clone the Git repository for SIGpi to your Raspberry Pi.
Finally, all you have to do now is cd SIGpi so that you can run the set up script for SIGpi.
./SIGpi_installer.sh
Now here is where the fun begins. Once you run the ./SIGpi_installer.sh and if everything was followed up until this point, you be greeted with a screen like this now in your terminal:
After using your tab key to allow you to hit enter, your next step will be to select the base applications for your installation.
A 32GB SD card at minimum is suggested for further expansion, but if you wish to use a 16GB card, you can select the options in this article to help keep your installation a little smaller for now.
The reason why we are providing an option for two versions of GNUradio is based on user preference.
Some people may prefer to still use the older 3.8 version since the architecture for 3.9 changed a bit. For most people who are interested in the more visual applications for SIGpi, either is fine and 3.8 may be fine for now.
In this step, your base visual SDR applications can be installed and we suggest getting familiar with SDRangel and also SDR++. Lighter weight applications like GQRX and CubicSDR are provided as options for convenience.
This step will be of more interest to amateur radio people interested in some digital modes specific to those activities mostly.
You can decide to always come back to install these if you like, but they are all pretty small and could not hurt to include all five in your initial installation.
This selection of useful applications will appeal to different people for different reasons. Some may already be familiar to some readers, but Artemis might be new as well as the HVDN HASviolet project which we snuck in here as well.
At any point after initial installation you can add these, but if you have a 32GB card or greater, it is more than ok to just select all of these and move on.
It is worth noting that the popular rtl_433, dump1090, radiosonde and a few other command line applications are already going to install automatically since they are small, but we chose to only highlight the larger applications in this menu tree for installation.
And now you are ready to hurry up and wait. Once you move past this menu, you will start to see a flurry of activity taking place with critical milestones highlighted during installation to know what steps you are up to.
Depending on your options selected, the total installation for the first time will take up to three hours in total. As the SIGpi progresses you will see colored bars like above letting you know what is comping up and what has just finished installation.
If you decide to include SDRangel, the wisdom files included for FFT will be worth the wait given all the underlying dependencies that F4EXB and his community have built into this great application.
The Artemis application and hamlib will also take a while, but as long as you can leave your Raspberry Pi connected to the internet and you can check in on it from time to time via your terminal, everything should run pretty smoothly.
Installed. Now what?
Suggestion from here is to just VNC into your Raspberry Pi and you will be greeted with some localization steps for Raspberry Pi like setting up a keyboard, time zone and warned that now is a great time to change the default password from "raspberry" to something else.
Once you have a look at the menus in the Raspberry OS, you will see many fun things to play with and explore signals around you.
A last recommendation before we close this article is that it is a good idea to plug your SDR into the Raspberry PI 4 USB 3.0 port (the blue ones!) to get more bandwidth for your SDR.
Perhaps starting with SDR++ or SDRangel is what got you excited, so hope you enjoy SIGpi.
When it comes time to update to a later version of the applications installed, you can learn about how to do that by visiting the SIGpi Git repository.
Future video, article, etc coming up to help better understand how to actually use the software and also how to update things when its needed with SIGpi.
https://github.com/joecupano/SIGpi
