Looking to expand the device capability I stumbled across a really interesting little project that is still in the early stages of development but, is functional and worth trying out.
The TC²-BBS Meshtastic Version is a simple BBS system that runs on a RaspberryPi, Linux PC or virtual machine (VM) and can connect to a Meshtastic device via either serial, USB or TCP/IP. Having my M0AWS-1 Meshtastic node at home connected to Wifi I decided to use a TCP/IP connection to the device from a Linux VM running the Python based TC²-BBS Meshtastic BBS.
Following the instructions on how to deploy the BBS is pretty straight forward and it was up and running in no time at all. With a little editing of the code I soon had the Python based BBS software M0AWS branded and connected to my Meshtastic node-1.
M0AWS Meshtastic BBS Main Menu accessible on M0AWS-1 node.
The BBS system is very reminiscent of the old packet BBS systems of a bygone era but, it is ideal for the Meshtastic world as the simple menus and user interface are easily transmitted in seconds via the Mesh using minimal bandwidth.
The BBS is accessible by opening a Direct Message session with the M0AWS-1 node. Sending the letter H to the node will get you the initial help screen showing the menu above and then from there onwards it’s just a matter of selecting the menu item and following the BBS prompts to use the BBS.
The BBS also works across MQTT. I tested it with Dave, G4PPN and it worked perfectly via the Meshtastic MQTT server.
This simple but, effective BBS for the Meshtastic network will add a new message store/forward capability to the Mesh and could prove to be very important to the development of the Meshtastic mesh in the UK and the rest of the world.
We’ve recently added a new room to the Matrix HAM Radio Space for Digital Voice modes as this was an area of interest that didn’t really fit into any of the other rooms.
The new Digital Voice room has attracted a lot of attention from members, with a lot of the focus being on the AllStarLink system. Michael, DK1MI built an AllStarLink node in the cloud for us all to use for Matrix Nets and so I decided I had to get in on the fun.
Jumbospot SHARI SA818 Amateur Radio AllStarLink Radio Interface Front Panel ViewJumbospot SHARI SA818 Amateur Radio AllStarLink Radio Interface Rear ViewJumbospot SHARI SA818 Amateur Radio AllStarLink Radio Interface stripped down View
The two USB connectors on the SHARI device are position such that they plug into two of the available 4 USB ports on the RaspberryPi without the need for cables. This keeps the whole solution together in one neat package.
Before you start you will need to obtain a node number and secret (password) from the AllStarLink Portal. To get this you will need to provide proof to the AllStarLink administrators that you are a licensed Amateur Radio (HAM) operator. This is done by uploading a copy of the first page of your HAM licence to the website for the admin team to check. This can take 24hrs to be completed so make sure you get this all done before trying to build your node. You cannot build a node successfully without a node number and secret.
Of course you will also need a transceiver that can operate on the 438.800Mhz frequency or other frequency of your choice on the 2m or 70cm HAM band.
You will also need to open port 4569 on your internet router and setup port forwarding to the IP Address that you will be using on your RaspberryPi node. It’s important to use a static IP Address on your RaspberryPi.
There are quite a few different Linux based operating system (O/S) images that are available for the RaspberryPi devices that have been specifically tailored for the AllStarLink node and include all the necessary software and library packages out the box.
Once downloaded you need to burn the ISO image onto a suitable SD card for your RaspberryPi. I use BalenaEtcher as it’s extremely quick and reliable at burning ISO images to SD cards.
Of course if you are a hardline Linux command line junkie you can always use dd to create the SD card.
Once you’ve got your O/S onto your SD card, slot it into your RaspberryPi making sure your SHARI device is connected to the two USB ports and then power it up. Make sure you have a good PSU for the RaspberryPi as the two devices together draw around 3A of current during the transmit cycle. (I use a 3.6A PSU from Amazon).
The default login for the Raspbian O/S is shown below. Login via SSH and configure your RaspberryPi for your local network. It’s important to use a static IP Address configured either directly on the RaspberryPi or via DHCP in your router.
Next you need to change directory into the asterisk config file directory using the command shown below:
cd /etc/asterisk
In this directory you will find all the default config files that come as part of the distro. For this build we’re not going to use them and so we need to move them out of the way ready for a set of config files that have already been configured correctly.
Using the following commands create a new directory, move into that new directory and then move all the unwanted configuration files into it:
mkdir ORIGINAL-CONF-FILES
cd ./ORIGINAL-CONF-FILES
mv ../*.conf ./
ls -la
cd ../
You should now be back in the /etc/asterisk directory which will now be empty apart from the custom directory which we left in place.
You now need to copy the correctly configured configuration files into the /etc/asterisk directory. Start by downloading the zip file containing the new configuration files
Once downloaded, copy the .zip file into the repeater users home directory (/home/repeater) using either scp on the Linux command line or if using Windows you can use the FileZilla Client in SFTP mode using the login details above.
Once you have the .zip file in the repeater user’s home directory you need to copy the file into the /etc/asterisk directory as user root:
The gpioBASH script and configuration details were supplied by Mark, G1INU in the Digital Voice room on the Matrix. It adds the COS light functionality to the setup. The COS light will now light every time the SA818 hears RF on the input.
The next thing you need to do is configure the SA818 radio device in the SHARI. The script I used was originally from https://wiki.fm-funknetz.de/doku.php?id=fm-funknetz:technik:shari-sa818 all I’ve done is change the entries to switch off CTCSS and changed the frequency to 438.800Mhz. Configuring the SA818 is done by running the SA818-running.pyPython programme that you moved into the repeater user home directory. Making sure you are still user root, run the following commands:
cd /home/repeater
./SA818-running.py
At this point your SHARI SA818 device will be configured to operate on 438.800Mhz and CTCSS will be disabled.
If you want to change the frequency or enable and set a CTCSS tone to access the node you will need to edit the Python programme using your favourite text editor and change the entries accordingly. Once changed rerun the program as shown above and your SHARI will be reconfigured to your new settings.
Next you need to move the allmon.ini.php file into the correct directory so that it enables access to the Allstar Monitor web page on the device so that you can manage connecting/disconnecting nodes. Use the following commands as user root to achieve this:
The allmon.ini.php file needs to have your node name entered into it for it to work correctly. As user root, change directory and edit the file using your favourite editor.
cd /var/www/html
Using your text editor, search for the line starting [XXXXX] and change the XXXXX to your node number. Save the change and exit the file.
At this point you are almost complete, all that is left to do is add your node number and node secret into the appropriate configuration files in the /etc/asterisk directory.
Since I am a Linux command line junkie I use vi to edit all the configuration files on the command line as user root, but you can use any editor of your choice.
cd /etc/asterisk
Start with the extensions.conf file. Search for the line starting with NODE = and delete the XXXXX entry and insert your node number. Save the file and edit it.
Next you need to edit the iax.conf file. This time search for the line starting with register= and change the XXXXX for your node number and the YYYYYYYYYYYY for your node secret. Be careful not to accidentally delete any other characters in the lines otherwise it will corrupt the configuration file.
In the same file search for the two lines that start with secret = and change the YYYYYYYYYYYY for your node secret. Once you have changed both of the secret entries, save and exit the file.
The final file to edit is the rpt.conf file. Once again open the file using your favourite editor and search for the line starting with XXXXX = radio@127.0.0.1:4569/XXXXX, change the XXXXX entries for your node number making sure not to delete any other characters next to the XXXXX entries.
Further down in the same file there is a line that starts with [XXXXX], once again change the XXXXX for your node number making sure to keep the square brackets at each end of the node number as you edit it.
Finally move down to the very bottom of the file and find the two lines that start with /home/repeater/gpio, once again change the XXXXX entries for your node number.
Once this is done, save and exit the file. At this point your node should be fully configured and will only require a reboot to get it working.
As user root, reboot your raspi using the reboot command.
reboot
Once your raspi comes back online, login using SSH as user repeater and then become root user using the sudo command detailed above.
You now need to create the admin user password for the Allstar Monitor web page on the device. This is done using the following commands as user root:
cd /var/www/html/
htpasswd -c .htpasswd admin
You will be asked to enter a password twice for the admin user, make sure you make a note of this password as you will need it to login to the web page.
Once this is done your configuration is complete, logout from the terminal session by entering exit twice (once to logout as user root and another to logout as user repeater).
Using your favourite web browser enter the IP Address of your raspi into the URL bar as shown below:
http://<Your-Raspi-IP>/allmon2
Note: remove the <> from the URL once you have entered the required information.
Once this is done you should be presented with your node control panel as shown below.
First visit to the AllStar Monitor Web Page
Login using Admin and the password you set above and you are now ready to start using your node.
It’s a good idea to connect to node 55553 which is a parrot test node to check your audio levels. you can do this by entering the node into the field at the top left and pressing the connect button.
M0AWS AllStarLink Node 61928 connected to 55553 Parrot
Once connected, tune your radio to 438.800Mhz FM and transmit a test message using your callsign and test123, or something similar. The parrot will then play your recording back to you so that you can hear how you sound. It will also comment on your audio level as to whether it is OK or not.
You are now connected to AllStarLink network and have the world at your finger tips. Below is a small list of nodes in the UK, Australia and America to get you started chatting with other HAMs via your node.
55553 ASL Parrot for testing
41522 M0HOY HUBNet Manchester, UK
60349 VK6CIA 439.275 Perth, Western Australia
51077 VK6SEG South West Hub B Albany WA
2167 M0JKT FreeSTAR UK HUB 2 freestar.network
53573 NWAG NW AllStar Group Lancashire, UK
27339 East Coast Hub Wilmington NC USA
M0AWS AllStarLink Node 61928 sitting on the equipment rack
Thanks to Michael, DK1MI for building and hosting the Matrix HAM Radio Space AllStarLink Node (57881) and getting us all kicked off into the world of AllStarLink!
We hope to be having regular Matrix Net’s on the node soon for all Matrix members and visitors. We’ll organise days/times via the Digital Voice room.
Following on from my article about my QO-100 Satellite Ground Station Complete Build, this article goes into some detail on the Node-RED section of the build and how I put together my QO-100 Satellite Ground Station Dashboard web app.
The Node-RED project has grown organically as I used the QO-100 satellite over time. Initially this started out as a simple project to synchronise the transmit and receive VFO’s so that the SDR receiver always tracked the IC-705 transmitter.
Over time I added more and more functionality until the QO-100 Ground Station Dashboard became the beast it is today.
M0AWS QO-100 Ground Station Control Dashboard built using Node-RED.
Looking at the dashboard web app it looks relatively simple in that it reflects a lot of the functionality that the two radio devices already have in their own rights however, bringing this together is actually more complicated than it first appears.
Starting at the beginning I use FLRig to connect to the IC-705. The connection can be via USB or LAN/Wifi, it makes no difference. Node-RED gains CAT control of the IC-705 via XMLRPC on port 12345 to FLRig.
To control the SDR receiver I use GQRX SDR software and connect to it using RIGCTL on GQRX port 7356 from Node-RED. These two methods of connectivity work well and enables full control of the two radios.
M0AWS Node-RED QO-100 Ground Station Dashboard Flow as of 12/06/24
The complete flow above looks rather daunting initially however, breaking it down into its constituent parts makes it much easier to understand.
There are two sections to the flow, the GQRX control which is the more complex of the two flows and the comparatively simple IC-705 section of the flow. These two flows could be broken down further into smaller flows and spread across multiple projects using inter-flow links however, I found it much easier from a debug point of view to have the entire flow in one Node-RED project.
Breaking down the flow further the GQRX startup section (shown below) establishes communication with the GQRX SDR software via TCP/IP and gets the initial mode and filter settings from the SDR software. This information is then used to populate the dashboard web app.
M0AWS Node-RED QO-100 Ground Station Dashboard – GQRX Startup Flow
The startup triggers fire just once at initial startup of Node-RED so it’s important that the SDR device is plugged into the PC at boot time.
All the startup triggers feed information into the RIGCTL section of the GQRX flow. This section of the flow (shown below) passes all the commands onto the GQRX SDR software to control the SDR receiver.
M0AWS Node-RED QO-100 Ground Station Dashboard – GQRX RIGCTL Flow
The TCP RIGCTL -> GQRX node is a standard TCP Request node that is configured to talk to the GQRX software on the defined IP Address and Port as configured in the GQRX setup. The output from this node then goes into the Filter RIGCTL Response node that processes the corresponding reply from GQRX for each message sent to it. Errors are trapped in the green Debug node and can be used for debugging.
The receive S Meter is also driven from the the output of the Filter RIGCTL Response node and passed onto the S Meter function for formatting before being passed through to the actual gauge on the dashboard.
Continuing down the left hand side of the flow we move into the section where all the GQRX controls are defined.
M0AWS Node-RED QO-100 Ground Station Dashboard – GQRX Controls Flow
In this section we have the VFO step buttons that move the VFO up/down in steps of 10Hz to 10Khz. Each button press generates a value that is passed onto the Set DeltaFreq change node and then on to the Calc new VFO Freq function. From here the new VFO frequency is stored and passed onto the communications channel to send the new VFO frequency to the GQRX software.
The Mode and Filter nodes are simple drop down menus with predefined values that are used to change the mode and receive filter width of the SDR receiver.
Below are the HAM band selector buttons, each of these will use a similar process as detailed above to change the VFO frequency to a preset value on each of the HAM HF Bands.
The QO-100 button puts the transmit and receive VFO’s into synchro-mode so that the receive VFO follows the transmit VFO. It also sets the correct frequency in the 739Mhz band for the downlink from the LNB in GQRX SDR software and sets the IC-705 to the correct frequency in the 2m VHF HAM band to drive the 2.4Ghz up-converter.
The Split button allows the receive VFO to be moved away from the transmit VFO for split operation when in QO-100 mode. This allows for the receive VFO to be moved away so that you can RIT into slightly off frequency stations or to work split when working DXpedition stations.
The bottom two Memory buttons allow you to store the current receive frequency into a memory for later recall.
At the top right of this section of the flow there is a Display Band Plan Info function, this displays the band plan information for the QO-100 satellite in a small display field on the Dashboard as you tune across the transponder. Currently it only displays information for the satellite, at some point in the future I will add the necessary code to display band plan information for the HF bands too.
The final section of the GQRX flow (shown below) sets the initial button colours and starts the Powermate USB VFO knob flow. I’ve already written a detailed article on how this works here but, for completeness it is triggered a few seconds after startup (to allow the USB device to be found) and then starts the BASH script that is used to communicate with the USB device. The output of this is processed and passed back into the VFO control part of the flow so that the receive VFO can be manually altered when in split mode or in non-QO-100 mode.
M0AWS Node-RED QO-100 Ground Station Dashboard – Powermate VFO Flow
The bottom flows in the image above set some flow variables that are used throughout the flow and then calculates and sets the RIT value on the dashboard display.
The final section of the flow is the IC-705 control flow. This is a relatively simple flow that is used to both send and receive data to/from the IC-705, process it and pass it on to the other parts of the flow as required.
M0AWS Node-RED QO-100 Ground Station Dashboard – IC-705 Control Flow
The IC-705 flow is started via the timestamp trigger at the top left. This node is nothing more than a trigger that fires every 0.5 seconds so that the dashboard display is updated in near realtime. The flow is pretty self explanatory, in that it collects the current frequency, transmit power, SWR reading, PTT on/off status and S Meter reading each time it is triggered. This information is then processed and used to keep the dashboard display up to date and to provide VFO tracking information to the GQRX receive flow.
On the left are the buttons to change band on the IC-705 along with a button to tune to the VOLEMT on the 60m band. Once again there two memory buttons to save and recall the IC-705 VFO frequency.
The Startup PTT Colour trigger node sets the PTT button to green on startup. The PTT button changes to red during transmit and is controlled via the Toggle PTT function.
At the very bottom of the flow is the set transverter IF Freq function, this sets the IC-705 to a preselected frequency in the 2m HAM band when the dashboard is switched into QO-100 mode by pressing the QO-100 button.
On the right of the flow there is a standard file write node that writes the 2.4Ghz QO-100 uplink frequency each time it changes into a file that is used by my own logging software to add the uplink frequency into my log entries automatically. (Yes I wrote my own logging software!)
The RX Audio Mute Control filter node is used to reduce the receive volume during transmit when in QO-100 full duplex mode otherwise, the operator can get tongue tied hearing their own voice 250ms after they’ve spoken coming back from the satellite. This uses the pulse audio system found on the Linux platform. The audio is reduced to a level whereby it makes it much easier to talk but, you can still hear enough of your audio to ensure that you have a good, clean signal on the satellite.
As I said at the beginning of this article, this flow has grown organically over the last 12 months and has been a fun project to put together. I’ve had many people ask me how I have created the dashboard and whether they could do the same for their ground station. The simple answer is yes, you can use this flow with any kind of radio as long as it has the ability to be controlled via CAT/USB or TCP/IP using XMLRPC or RIGCTL.
To this end I include below an export of the complete flow that can be imported into your own Node-RED flow editor. You may need to make changes to it for it to work with your radio/SDR but, it shouldn’t take too much to complete. If like me you are using an IC-705 and any kind of SDR controlled by GQRX SDR software then it’s ready to go without any changes at all.
I get quite a few emails from readers of my blog asking how my QO-100 satellite station is put together and so, I thought perhaps now is a good time to put together an article detailing the complete build.
My QO-100 satellite ground station is built around my little Icom IC-705 QRP transceiver, it’s a great little rig and is ideal for the purpose of driving a 2.4Ghz transverter/up-converter.
Of course all the software used for the project is Opensource and freely available on the internet.
M0AWS QO-100 Ground Station Build Visual (Click to Enlarge)
The station comprises of the following building blocks:
QO-100 Ground Station Dashboard developed using Node-RED
LMR400-UF/RG58 Coax Cable
M0AWS QO-100 1.1m (110cm) off-set Dish with IceCone Helix antenna and Bullseye LNB.
To get a good clear view of the QO-100 satellite I have the dish mount 3.2m above the ground. This keeps it well clear of anyone walking past in the garden and beams the signal up at an angle of 26.2 degrees keeping well clear of neighbouring gardens.
The waterproof enclosure below the dish houses all the 2.4Ghz equipment so that the distance between the feed point and the amplifier are kept to a minimum.
The DXPatrol amplifier is spec’d to run at 28v/12w or 12v/5w, I found that running it at 28v produced too much output for the satellite and would cause the LEILA alarm on the satellite to trip constantly. Running the amp at 12v with a maximum of 5w output (average 2.5-3.5w) is more than enough for me to have a 5/9+10 signal on the transponder.
The large 1.1m dish gives me quite an advantage on receive enabling me to hear the very weak stations with ease compared to other stations.
2.4Ghz ground station enclosure ready for testing
The photo above shows the 2.4Ghz equipment mounted in the waterproof enclosure below the dish. This photo was taken during the initial build phase before I rewired it so, the amplifier is shown connected to the 28v feed. To rewire the amp to 12v was just a matter of removing the 28v converter and connecting the amp directly to the 12v feed instead. This reduced the output from a maximum of 12w down to a maximum of 5w giving a much better (considerate) level on the satellite.
It’s important to keep all interconnects as short as possible as at 2.4Ghz it is very easy to build up a lot of loss between devices.
For the connection from the IC-705 to the 2.4Ghz Up-Converter I used a 7m run of LMR-400 coax cable. The IC-705 is set to put out just 300mW on 144Mhz up to the 2.4Ghz converter and so it’s important to use a good quality coax cable.
Once again the output from the 2.4Ghz amplifier uses 1.5m of LMR-400-UF coax cable to feed up to the 2.2 turn Icecone Helix Antenna mounted on the dish. This keeps loss to a minimum and is well worth the investment.
Bullseye 10Khz High Stability Unversal Single LNB for 10.489-12.750Ghz
The receive path starts with a Bullseye LNB, this is a high gain LNB that is probably one of the best you could use for QO-100 operations. It’s fairly stable frequency wise but, does drift a little in the summer months with the high temperature changes but, overall it really is a very good LNB.
The 12v feed to the LNB is via the coax and is injected by the Bias-T device that is in the radio shack. This 12v feed powers the LNA and associated electronics in the LNB to provide a gain of 50-60dB.
Bias-T to inject 12v feed into the coax for the Bullseye LNB
From the Bias-T the coax comes down to the NooElec SmartSDR receiver. This is a really cheap SDR device (<£35 on Amazon) based on the RTL-SDR device but, it works incredibly well. I originally used a Funcube Dongle Pro+ for the receive side however, it really didn’t handle large signals very well and there was a lot of signal ghosting so, I swapped it out for the NooElec SDR and haven’t looked back since.
The NooElec SmartSDR is controlled via the excellent Opensource software GQRX SDR. I’ve been using GQRX SDR for some years now and it’s proven itself to be extremely stable and reliable with support for a good number of SDR devices.
To enhance the operation of the SDR device I have added a Griffin Powermate VFO knob to the build. This is an old USB device that I originally purchased to control my Flex3000 transceiver but, since I sold that many moons ago I decided to use it as a VFO knob in my QO-100 ground station. Details on how I got it working with the station are detailed in this blog article.
Having the need for full duplex operation on the satellite this complicates things when it comes to VFO tracking and general control of the two radios involved in the solution and so I set about creating a QO-100 Dashboard using the great Node-RED graphical programming environment to create a web app that simplifies the management of the entire setup.
M0AWS QO-100 ground Station Control Dashboard built using Node-RED.
The QO-100 Dashboard synchronises the transmit and receive VFO’s, enables split operation so that you can transmit and receive on different frequencies at the same time and a whole host of other things using very little code. Most of the functionality is created using standard Node-RED nodes. More info on Node-RED can be found on the Opensource.radio Wiki or from the menu’s above.
I’ll be publishing an article all about the QO-100 Dashboard in the very near future along with a downloadable flow file.
I’m extremely pleased with how well the ground station works and have had well in excess of 500 QSO’s on the QO-100 satellite over the last last year.
The Heltec ESP32 v3 LORA devices have a coil type Bluetooth/Wifi antenna on the PCB from the factory. This antenna doesn’t work particularly well and has very limited range so, I decided to do something about it.
Getting out the calculator a quarter wave at 2400Mhz is 29.7mm. Looking at the coil antenna on the PCB I decided the best way to connect the new antenna would be to solder it to the coil of the existing antenna. This would short out the coil completely whilst creating a solid mount point for the new antenna.
After a little measuring I decided to use a 31mm long piece of 1.5mm hard core mains cable for the new antenna. I stripped back the insulation from one end of the wire so that the exposed copper wire was exactly the length to short across all the windings of the coil antenna on the PCB.
Attaching replacement Bluetooth Antenna to the Heltec ESP32 v3 Device
Attaching the the wire to the coil was easy enough to do but, it’s worth pointing out that you need to be quick so that the heat doesn’t transfer down onto the PCB desoldering the coil antenna from the device.
Whilst tinkering with the Bluetooth antenna I decided I would also make a neat little quarter wave 868Mhz vertical antenna for this device whilst I had it all apart. This is my Meshtastic node-2 and it’s sole purpose is to allow me to use my iPad to send/receive messages via bluetooth which are then forwarded on to my base node-1 in the house. Node-1 is connected to the house wifi and the Meshtastic MQTT server. This combination allows me to message people on the mesh even though there are no local nodes within RF range.
Running the numbers for the 868Mhz antenna the vertical will need to be around 82.1mm long with a radial of similar length. I had to hand a very nice SMA to N Type chassis mount socket that would be ideal to mount the antenna to the case. I drilled out the holes in the case, measured out the wires and attached it all to the case. Connecting the antenna to the N Type socket I connected my VNA and set about tuning the antenna to resonance.
M0AWS Hidden Radial for the 868Mhz Heltec Antenna
Squeezing the radial and SMA connector into the case I realised I really could do with a 90 degree SMA connector so, I quickly ordered one from Amazon which will be delivered tomorrow. Connecting up my VNA, I had to trim the antenna down to get it to resonance. The SWR ended up at 1.2:1 which is ideal. I ended up cutting off more wire than I thought I would to get the antenna to resonance but, this is due to the extra capacitance caused by the insulation on the wire. If I had used bare copper wire then I wouldn’t of had to cut so much off. I eventually ended up with around 72.9mm of wire for both the antenna and radial.
M0AWS Heltec ESP32 v3 Device with replacement Bluetooth and 868Mhz Antennas
Putting the device back into the case and connecting the USB battery the device fired up and immediately connected to my node in the house. Checking the signal strength of node-1 in the house I could see a 7dB increase in signal strength compared to the little wire antenna that comes with the device. This is a significant improvement for such a simple antenna and well worth the effort.
Next I had to drill a hole in the front of the Heltec case so that the Bluetooth antenna could poke out the front and be bent up vertically. This worked out really well and improved the Bluetooth range massively.
M0AWS Completed alterations to the Heltec ESP32 v3 antennas
Putting the node back in the house and taking my iPad down to the end of the garden some 30m away I could instantly connect to the device via Bluetooth from my iPad, something I’d not been able to do prior to adding the new antennas. I can now use the Heltec device via Bluetooth from anywhere in the house or garden making it much more accessible.
It’s amazing the difference an hour and two little pieces of wire can make to these devices and is well worth the effort.
The loading of the Meshtastic firmware on the Heltec ESP32 v3 devices is really simple if done via a Linux PC/RaspberryPi. There are of course other ways to load the firmware using a web browser that supports USB/Serial devices and this method is preferred by many however, being a Linux command line junkie I far prefer the simplicity of using the Linux command line to do the job.
So, how much experience with the Linux command line do you need?
In all honesty none at all. If you know how to use copy and paste then all you have to do is follow the simple steps I’ve detailed below. In reality it will only take a few minutes to do so, don’t be put off by the long article, I’ve just tried to cover everything and provide screen shots along the way.
To get started fire up your Linux PC/RaspberryPi and get yourself to the desktop. Next you will need to open a Linux command line terminal. This is often just called “Terminal” on most Linux desktop installations.
The first thing you need to do is check to see if you have python3 installed. This is done using the following command:
python3 --version
Running the above command you should see a result something like what is shown below.
Python3 command showing installed version
Next we need to check if pip3 is installed using the following command:
pip3 --version
If pip3 is installed then you should get a result similar to that shown below.
Pip3 command showing installed version
If your computer doesn’t have Python3 or Pip3 installed they can be easily installed from the command line. To install Python3 enter the following command into your terminal:
sudo apt install python3
You will be asked to enter your login password and then the installation will begin. You should see output in your terminal similar to that shown below.
Installing python3
To install Pip3 enter the following command into your terminal:
sudo apt-get install python3-pip
This will detail a long list of packages that will be installed on your computer, Enter Y to answer Yes and let the packages install.
M0AWS – Installing Pip3
You will see many messages scroll up the terminal screen such as getting, selecting, preparing, unpacking and setting up, this is all normal.
Once Pip3 is installed you should be dropped back at the command line with a terminal screen that looks something like the one below.
M0AWS – Pip3 install complete
At this point you will now have Python3 and Pip3 available on your computer.
You are now ready to install the tool we are going to use to check your Meshtastic device is connected to your PC and install the firmware to it. (Do not connect your Meshtastic device to your PC just yet!)
Run the following command in your terminal to install the ESP Tool:
pip3 install --upgrade esptool
You will see an output from the installation process similar to that shown below.
M0AWS – Installing the ESP Tool
Now that we have the ESP tool installed plug your Meshtastic device into your USB port on your computer and then run the following command to interrogate the device to find out what kind of device it is.
esptool chip_id
You should see the information about your device that looks similar to that shown below. This information should confirm the device type (ESP32) and which USB port it is connected on (/dev/tty/USB0).
M0AWS – Expected output from the ESPTool command showing device information
Once you have this information you will need to download the firmware for your device from Github using the following URL:
https://github.com/meshtastic/firmware/releases
At the time of writing this I downloaded and used the v2.2.22.404d firmware which I have found to be extremely reliable.
In your terminal you now need to change directory (cd) into the Downloads directory where your downloaded firmware should be. (If you downloaded your firmware into another directory then you will need to cd into that directory). Use the following command to change directory into the Downloads directory.
cd ~/Downloads
Now we need to find the filename of the firmware we have just downloaded, we can use the list directory contents command to find the file using the simple command below.
ls -la firm*.zip
M0AWS – List firmware file name from the Linux command line
In the screenshot above we can see that the filename is called firmware-2.2.22.404d0dd.zip. We now need to unzip the file using the unzip command.
unzip firmware-2.2.22.404d0dd.zip
You’ll see lots of output from the unzip command about inflating files etc, this is normal.
Once the file has been unzipped you are ready to load the firmware onto your Heltec device. First you need to find the .bin file for your Heltec device. Use the following ls command to list the files available.
ls -la firmware-heltec*
This will list out all the firmware file options for the Heltec device as shown below.
M0AWS – List of Heltec firmware files
The file you need to use for a new firmware installation on a Heltec v3 device is firmware-heltec-v3-2.2.22.404d0dd.bin. (If you downloaded a different version then the version number in the file will be different).
Using the filename you found above enter the following command into your terminal.
This will now clear down your Heltec device and will load the Meshtastic firmware. This will take a little time especially on slower computers like the RaspberryPi so, just let it run until it finishes. Do not interrupt the process whilst it is running.
Installing the Meshtastic firmware onto my Heltec ESP32 v3 using the Python command line tool
Once the firmware is loaded the Heltec device will reboot and you will see the Meshtastic banner on the OLED screen. Your device is now ready for configuration.
Now that you have Python3 and Pip3 installed you can load the firmware onto other devices just by downloading the firmware and then running the device-install.sh script file, you won’t need to install Python3 or Pip3 again.
If you want to update your device in the future to a newer version of the firmware then just use the update script and update binary file as shown below.
Meshtastic is a relatively new thing in the internet of things (IOT) world and is gaining traction in the U.K. at the moment.
So what is Meshtastic?
Meshtastic is an open source, off-grid, decentralised mesh network built to run on affordable, low-power devices on the 868Mhz industrial, scientific, and medical (ISM) band. (Some devices can also run on the 433Mhz 70cm HAM band.)
The ISM band is licence free but, has limits on the RF power levels that can be used. The one plus over the HAM bands is that you can legally transfer encrypted messages over the ISM band making it secure.
The best way to think of Meshtastic is a radio version of the online decentralised Matrix chat system but, without the large server requirements and ever growing database!
Heltec ESP32 v3 Wifi, Bluetooth and 868Mhz device for Meshtastic
There are quite a few Meshtastic compatible devices on the market today with many costing around the £20 mark whilst others like the LillyGo T-Echo costing over £100 in the U.K. even though they are less than half the price in the USA.
Since I’m just starting out on my Meshtastic adventure I thought I’d start with a pair of Heltec ESP32 v3 devices that are normally readily available on Amazon but, due to the current push to build a U.K. wide mesh, they are currently out of stock pretty much everywhere.
Loading the Meshtastic firmware onto the devices is fairly straight forward and can be done using the web installer via either the Edge or Chromium web browsers. (Note: If using Windows O/S you will need to install some drivers from the Meshtastic website to be able to communicate with the devices)
Having neither of the two browsers and being a Linux command line junkie I decided to use the Python programme to load the firmware onto the two devices. It’s worth noting that you don’t need any drivers to be able to communicate with the devices if you’re using either Debian or one of the many Ubuntu flavours of Linux O/S.
Using the Python command line program sounds like a more complicated approach but, in reality it’s super simple, extremely reliable, quick and if like me you use a Linux PC in the radio shack then you most likely already have most of what you need to get the job done. Just follow the simple steps as laid out on the Meshtastic web site and you’ll have the firmware loaded in no time at all.
Installing the Meshtastic firmware onto my Heltec ESP32 v3 using the Python command line tool
The firmware takes less than a minute to copy across to the Heltec device and is automatically rebooted ready for configuration once the transfer has completed.
It is possible to configure the device via the command line tool however, since there is a nice GUI app for both Apple iOS and Android devices I decided to install the Meshtastic app on my iPad and connect to the device via Bluetooth to configure it.
Once you’ve got the Meshtastic app installed on your device and have connected via Bluetooth you’ll be ready to start configuring the device to join the mesh. The first thing you want to do is set the region. This is different in each country but, in the UK we use the EU_868 region settings. This will set the device to use the 868Mhz ISM band which is the band being used to build the U.K. wide mesh.
View of the Meshtastic app on iOS showing the configuration options for the Heltec ESP32 v3
There is a multitude of configuration options within the app which I will go into in greater detail in a series of articles at a later date.
Heltec ESP32 v3 running Meshtastic Firmware
For those of you that, like me aren’t near any other nodes you can connect the devices to the internet and use the Meshtastic MQTT server to communicate with other nodes. This of course isn’t off-grid but, it will get you started until the mesh grows into your local area at which point your device will automatically start communicating with the other nodes over radio.
Meshtastic MQTT connectivity
Once you are connected to either the MQTT server or other nodes via radio you will see the other node details appear in the Meshtastic app. It’s interesting to look at the information and see signal strengths and traffic levels etc for each node.
View of the Meshtastic app on iOS showing Nodes in the Mesh and Device Metrics for the M0AWS-1 Node
There are a multitude of cases available for the Heltec v3 devices, especially if you have access to a 3D printer. One of the nicest cases I have seen is the Bender from IKB3D (I know, it’s a strange name!) but, it really is a super little case for the Heltec series of devices.
Bender case for Heltec ESP32 v3 devices
You can either buy the 3D print files for £8.99 and print it yourself or just order a pre-printed and assembled case directly from the website although, due to demand there is a long lead time currently.
Modification of SI4732-A10 for full HF band reception on UV-K5
I will guide you on applying SI4732-A10, which is mainly used in shortwave radios that support SSB, to UV-K5. Firmware Version CEC_0.1HF
This version is different from the existing CEC series of UV-K5
This version is a test version for devices in which the FM radio chip BK1080 of the UV-K5 radio has been removed and replaced with SI4732-A10.
Do not upload to your radio if you have not modified the hardware
When the source of UV-K5 CEC version is released (Release 1.0), you will be able to run SI4732-A10 through Makefile options
1. Parts
1.1 SI4732-A10 * 1
If you search SI4732-A10 on Google, you will find various shortwave receivers. It has been popular with many people for several years due to its pretty good performance.
You can buy it on aliexpress for about $2.xx
There are several versions of SI4732, but the one that supports SSB is the one with A10. You must purchase SI4732-A10
1.2 X-tal 32.768Khz * 1
1.3 Capacitor 15~35pF * 2 (When purchasing crystal, purchase it in the recommended dosage. Approximately 22pF works in most cases)
1.4 Capcitor 100uF * 1 (or 50uF ~ 200uF)
1.5 Registor 10~15K * 1
2.circuit diagram
The red numbers shown in the circuit diagram below are the pin numbers for the existing BK1080.
In the circuit below, the letters 3 and 4 mean to connect to both numbers 3 and 4
To use FM radio, you must connect a separate antenna. However, even if you only use AMI, you can hear a strong FM signal well. (If you want to improve FM radio performance, you must implement and connect a separate antenna or SPLITTER)
I wrote numbers on the PCB board below.
If you feel the sound is low, connect to POINT.A instead of 3 or 4.
3.Tip
It is difficult to make it in a general PCB form due to lack of space.
I stuck the SI4732-A10 upside down on double-sided tape and soldered the parts.
Before attaching, make sure the lid closes well before connecting.
If you can replace your existing speakers with smaller ones, you can use a regular PCB.
4.operate
A representative product of SI-4732 is the ATS-20 in the picture below. I created the firmware by referring to the ATS-20's screen interface.
Buttons
Number 0 : Long Press -> Enter SI4732-A10 Mode
Exit : Long Press -> Exit SI4732-A10 Mode
UP / DOWN : Frequency Up or Down (Step)
Side Button : Frequency 1Mhz Up or Down
Number 1 : Change Bandwidth (use LSB or USB mode)
Number 4, Number 7 : BFO Frequency Up/Down, This function allows adjustment in Hz units in SSB mode.
Number 2 : AGC ON/Off
Number 5 : Att Manual Mode (AGC Off) and Att change
Star (*) : Step Change (1 -> 5 -> 10 -> 20 -> 50)
F (Function): Short Press : change mode AM <-> FM or LSB <-> USB
I did the SI4732 MOD a few months ago. At the time, I didn't have a circuit diagram, so I checked it by scraping the pattern on the board with a cutter knife, and a grateful radio amateur (IU0AZB)sent it to me last night.
If you want to improve reception performance, you can try changing the boxed areas below.
In particular, simply removing all the parts in the red B square will slightly improve reception performance.
A few years ago, I made a receiver with the SI4735, a model similar to the SI4732-A10, and due to the characteristics of the radio chip, I used a transformer to increase the impedance. I experienced a tremendous improvement in reception performance. However, interference waves are also quite strong, so a filter (FMI, AMI) must be used.
The space where we work is small. I hope that the various experiments of amateur radio operators will yield good results.
6.3 TODO : Removing the crystal and two capacitors
We are examining whether three components can be removed by using an external clock (BK4819's reference clock - Checked by IU0AZB)
I experimented a few times, but it didn't work. I suspect an interference problem due to the reset circuit, which is different from the original circuit and is configured as analog, or my experimental environment.
If successful, only SI4732 and two components (C1, R1) are needed.
I’ve been gradually building my QO-100 ground station over the last few months and have had the receive path working for some time now. One of the things I really miss with the Funcube Dongle Pro+ (FCD) SDR is a real VFO knob for changing frequency.
My QO-100 Node Red dashboard is configured so that I can have the FCD track the uplink frequency from the IC-705 but, sometimes I use the FCD without the IC-705 in the shack and so a physical VFO would be handy.
Many years ago when I lived in France (F5VKM) I had a Flexradio Flex-3000 SDR, a great radio in it’s time and one that gave me many hours of enjoyment. One addition I bought for that station was a Griffin Technology Powermate VFO knob. It worked extremely well with the PowerSDR software for the Flex-3000 and I used it for many years.
Many years later I’m back in the UK and much of my equipment is packed away in the attic, including the Griffin Technology Powermate VFO.
I decided to dig it out and see if I could get it working with GQRX SDR software. Sadly I couldn’t get it working with GQRX however, I did find a way of getting it working with Node Red and thus could add it to my QO-100 Node Red Dashboard and then control GQRX with it via a simple Node Red flow.
Griffin Technology Powermate VFO
Plugging the Powermate VFO into my Kubuntu PC it wasn’t immediately recognised by the Linux O/S. After a little searching I found the driver on Github. I added the PPA to my aptitude sources and installed the driver using apt.
Once installed the default config for the Powermate device is to control the default audio device volume. To make the device available for use as a VFO knob you need to change the configuration so that the default setting is disabled. To do this is relatively easy, just edit the config file using your favourite command line editor (Vi/Vim in my case) and add the following entry.
vi /etc/powermate.toml
# Entry to control HDMI volume with Powermate
#sink_name = "alsa_output.pci-0000_01_00.1.hdmi-stereo"
# Set powermate not to work with volume control
sink_name = ""
As shown above, comment out the default “sink_name” entry (Yours may be different depending on audio device in your PC) and add in the Powermate “sink_name” entry that effectively assigns it to nothing.
Once this is done, save the file and exit your editor and then reboot the PC.
Next you’ll need to install a small program called evtest.
sudo apt install evtest
To check the evtest program has installed correctly, plugin your Powermate VFO to any available USB port and run the following command in a terminal.
evtest /dev/input/powermate
Turning the Powermate knob you should see output on the screen showing the input from the device. You should also see BTN events for each press of the Powermate device.
Input driver version is 1.0.1
Input device ID: bus 0x3 vendor 0x77d product 0x410 version 0x400
Input device name: "Griffin PowerMate"
Supported events:
Event type 0 (EV_SYN)
Event type 1 (EV_KEY)
Event code 256 (BTN_0)
Event type 2 (EV_REL)
Event code 7 (REL_DIAL)
Event type 4 (EV_MSC)
Event code 1 (MSC_PULSELED)
Properties:
Testing ... (interrupt to exit)
Event: time 1685816662.086666, type 2 (EV_REL), code 7 (REL_DIAL), value -1
Event: time 1685816662.086666, -------------- SYN_REPORT ------------
Event: time 1685816662.318638, type 2 (EV_REL), code 7 (REL_DIAL), value -1
Event: time 1685816662.318638, -------------- SYN_REPORT ------------
Event: time 1685816662.574615, type 2 (EV_REL), code 7 (REL_DIAL), value -1
Event: time 1685816662.574615, -------------- SYN_REPORT ------------
Event: time 1685816663.670461, type 2 (EV_REL), code 7 (REL_DIAL), value 1
Event: time 1685816663.670461, -------------- SYN_REPORT ------------
Event: time 1685816664.030421, type 2 (EV_REL), code 7 (REL_DIAL), value 1
Event: time 1685816664.030421, -------------- SYN_REPORT ------------
Event: time 1685816664.334389, type 2 (EV_REL), code 7 (REL_DIAL), value 1
Event: time 1685816664.334389, -------------- SYN_REPORT ------------
Event: time 1685816665.334255, type 1 (EV_KEY), code 256 (BTN_0), value 1
Event: time 1685816665.334255, -------------- SYN_REPORT ------------
Event: time 1685816665.558230, type 1 (EV_KEY), code 256 (BTN_0), value 0
Event: time 1685816665.558230, -------------- SYN_REPORT ------------
Event: time 1685816666.030161, type 1 (EV_KEY), code 256 (BTN_0), value 1
Event: time 1685816666.030161, -------------- SYN_REPORT ------------
Event: time 1685816666.182151, type 1 (EV_KEY), code 256 (BTN_0), value 0
Event: time 1685816666.182151, -------------- SYN_REPORT ------------
At this point you’re ready to stop evtest (CTRL-C) and then create the following little BASH shell script that Node Red will run to collect the O/P from the Powermate USB device.
#!/bin/bash
###############################################
# Griffin Technology Powermate control script #
# for Node Red. #
# #
# 04/06/23 - M0AWS - v0.1 #
# #
###############################################
VAL="1"
echo "STEP-1Hz"
/usr/bin/evtest /dev/input/powermate | while read LINE
do
case $LINE in
*"(REL_DIAL), value 1") echo "$VAL"
;;
*"(REL_DIAL), value -1") echo "-$VAL"
;;
*"(BTN_0), value 1") case $VAL in
"1") VAL="10"
echo "STEP-10Hz"
;;
"10") VAL="100"
echo "STEP-100Hz"
;;
"100") VAL="1000"
echo "STEP-1Khz"
;;
"1000") VAL="10000"
echo "STEP-10Khz"
;;
"10000") VAL="1"
echo "STEP-1Hz"
;;
esac
;;
esac
done
Once the BASH script is copied and pasted into a file called powermate.sh you need to make it executable by using the following command.
chmod 700 ./powermate.sh
If you now run the shell script in a terminal you’ll see a similar output to that shown below from the device when used.
As you can see above the shell script outputs a positive or negative number for VFO tuning and changes the VFO step size each time the Powermate is depressed.
Getting this output from the BASH shell script into Node Red is really simple to achieve using just 3 or 4 nodes.
In the Node Red development UI create the following nodes.
Griffin Powermate Node Red Nodes
The first node in the flow is a simple inject node, here I called it trigger. This sends a timestamp into the next node in the flow at startup to set the flow running.
The Griffin Powermate node is a simple exec node that runs the script we created above.
M0AWS Powermate exec node
Configure the node as shown above and connect it to the inject node that’s used as a trigger. Note: Change “user” in the Command field shown above to that of your username on your Linux PC)
Once done create the third node in the flow, a simple switch node and configure as shown below.
Switch Node for Powermate
The switch node has two outputs, the top one is a text output that is fed into a text field to show the current step size of the Powermate device and the lower output is the numeric output that must be fed into your VFO control flow so that the VFO value is incremented/decremented by the amount output by the Powermate device.
I’ve found the Griffin Technology Powermate USB device works extremely well with Node Red and GQRX that I use for controlling the FCD SDR radio and it’s now part of my QO-100 ground station build.
M0AWS QO-100 Dashboard with Powermate Step Display at bottom
As shown above you can see the Powermate Step size at the bottom of the dashboard, this text changes each time the Powermate device is depressed and will set a step size of 1Hz, 10Hz, 100Hz, 1Khz, 10Khz in a round-robin fashion.
The next stage of the build is the 2.4Ghz transmit path. I now have all the necessary hardware and so this part of the build can finally commence.
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