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Tag: meshtastic

  • Meshtastic solar repeater and client node setup

    ** this post is under construction **

    == Repeater setup ==

    Requisites:

    – solar charged
    – battery powered
    – low temp Li-ion charge cutoff
    – low power
    – no gps module due to fixed location
    – advantageous location
    – reliable/durable
    – medium gain antenna

    Materials:

    Soldering iron. Whatever you have should work, no fancy soldering required

    Heatshrink tubing https://www.amazon.com/Wirefy-180-Heat-Shrink-Tubing/dp/B084GDLSCK/

    RAKwireless WisBlock Meshtastic Starter Kit US915 https://store.rokland.com/products/rak-wireless-wisblock-meshtastic-starter-kit

    Optional GPS module https://store.rokland.com/products/rak-wireless-rak12500-gnss-gps-location-module-u-blox-zoe-m8q

    Outdoor, 915mhz, dipole antenna https://www.mouser.com/ProductDetail/712-ANT-8-9-IPW1SMA

    18650 Battery holder https://www.amazon.com/dp/B098SS1XYG

    Nitecore low temp battery https://www.18650batterystore.com/products/nitecore-nl1835lthp-18650-3500mah-8a-low-temperature-battery

    JST 2.0 Ph 2-Pin Connector Plug Male with 150mm Cable & Female https://www.amazon.com/dp/B01DUC1O68

    JST ZH1.5mm 2PIN Micro Electrical Male and Female Connector Plug with 150mm Wire Cables **this is only needed if you want to bypass the low temp charge controller and plug in direct to the onboard RAK solar plug** https://www.amazon.com/dp/B0B58M7D49

    5w solar panel https://www.amazon.com/Dzees-USB-C-Solar-Panel-360%C2%B0Adjustable/dp/B0CT355XFY/

    Adafruit solar charger with low temp cutoff https://www.adafruit.com/product/4755

    10k thermistor https://www.adafruit.com/product/372

    Male DC Power adapter – 2.1mm plug to screw terminal block https://www.adafruit.com/product/369

    Insulated enclosure https://www.harborfreight.com/brands/apache/1800-weatherproof-protective-case-small-black-64550.html

    Camo the PV and Enclosure https://www.rustoleum.com/product-catalog/consumer-brands/specialty/camouflage-spray-paint

    The Rak Wisblock is the perfect choice for a repeater. Its low power, modular and extremely reliable. You can purchase the starter kit which comes with the base board (RAK19007) and the Lora + bluetooth chip (RAK4631). It comes with PCB antennas (0.8dBi) that we won’t use for this fixed repeater. Always keep the antennas connected before powering the radio! Lack of antenna load will result in damage to the radio chip.

    Lets start by setting up the Rak wisblock for Meshtastic firmware

    Download the version of Meshtastic that suites you. Go through the change log to help you decide https://github.com/meshtastic/firmware/releases

    Here is the link to the latest stable https://github.com/meshtastic/firmware/releases/latest

    unzip firmware-2.3.10.d19607b.zip

    locate the firmware file for the wisblock 4631. Its called “firmware-rak4631-2.3.10.d19607b.uf2” (replace the 2.3.10…. with whatever fw version your using)

    plug the wisblock into your computer and double tap the button shown below.

    This will expose a mountable filesystem that you can copy the firmware image into.

    copy “firmware-rak4631-2.3.10.d19607b.uf2” onto the RAK4631 mount point. It might have current.uf2, index.htm and info_uf2.txt, don’t mess with those. Just copy and paste the “firmware-rak4631-2.3.10.d19607b.uf2” file into the RAK4631 partition. The green light will flash while its transferring and it will reboot when done. The firmware is now loaded and we move onto programming the radio with meshtastic software.

    We will be using the CLI (command line interface) meshtastic python script. https://meshtastic.org/docs/getting-started/initial-config/

    start by creating your python environment for interfacing with the RAK firmware operating system. https://meshtastic.org/docs/getting-started/initial-config/

    We will use pip to install meshtastic and create a python virtual environment to control the version of binaries and all the dependencies needed. These instructions are for Debian, of course ;-)

    sudo apt-get update
    sudo apt-get install python3
    sudo apt-get install python3-pip

    lets create a working directory for meshtastic

    mkdir meshtastic
    
    cd meshtastic

    Now create the virtual environment for python

    mkdir python

    python3 -m venv python/

    Enter the virtual environment and install meshtastic esptool and all its dependencies

    source python/bin/activate

    pip install --upgrade esptool meshtastic

    Anytime in the future when you need to use meshtastic you will enter the python virtual environment with

    source meshtastic/python/bin/activate

    This way you can control the versions of meshtastic and esptool without affecting any other versions of the python scripts, binaries and dependencies on your system.

    Now we can program the RAK radio

    to see whats currently programmed run

    meshtastic --info

    If this radio has been used before or you want to be sure of a blank slate run a factory reset

    meshtastic --factory-reset

    Now the radio can be setup from scratch. “Region US” sets the radio up for use in the USA at 915mhz

    meshtastic --set lora.region US

    set the name of this node

    meshtastic --set-owner [name]

    I like to set a preset bluetooth pin so I can easily access it locally over bluetooth from android phone using the meshtastic app.

    meshtastic --set bluetooth.mode FIXED_PIN

    the pin must be 6 characters long

    meshtastic --set bluetooth.fixed_pin 123456

    designate this as a router. Here is a description of what this means https://meshtastic.org/docs/configuration/radio/device/

    meshtastic --set device.role ROUTER

    Since this wisblock does not have the gps module (since its fixed location and conserves power) you will need to set its location manually. You can add a GPS module with the RAK12500 GNSS GPS Location Module.

    meshtastic --set position.fixed_position true --setlat 38.88987 --setlon -77.00971
    meshtastic --ch-set name family --ch-index 0

    use “psk random” for high encryption aes256

    meshtastic --ch-set psk random --ch-index 0

    Add a admin channel to this repeater so you can remotely administer the hardware. Unfortunately, this admin channel needs to be added to both nodes in order for administration features to work. This means that if someone physically gains access to this device they will have access to your channels encryption key and the admin key. So communications can be decrypted and they can remotely administer other nodes that have this admin channel.

    meshtastic --ch-add admin

    run –info again to confirm changes

    meshtastic --info

    you should see things like

    
    Owner: raktest (49aa)
    ....
      "device": {
        "role": "ROUTER",
    ....
        "position": {
          "latitudeI": 388898700,
          "longitudeI": -770097100,
          "latitude": 38.88987,
          "longitude": -77.00971
    
    ....
      "bluetooth": {
        "enabled": true,
        "mode": "FIXED_PIN",
        "fixedPin": 123456
    ....
    Channels:
      Index 0: PRIMARY psk=secret { "psk": "McyfwZfTvif/Ig6KTf5zWX0JxzFdYLPJeKYi91lhxpA=", "name": "family",
    ....
    Index 1: SECONDARY psk=secret { "psk": "w5idYjeyhw1e5jHL5EjjQuDwEH6iqZckSbzXgZNSfGA=", "name": "admin",

    And finally the channels URL. These URL’s hold the encryption key and name of the channel. Use these to add future devices to the mesh. The last “Complete URL” additionally contains the admin channel so only use that for nodes that you want to use for remote administration and devices that you want to be able to remotely administer. I will go over client configs later in this post using a tbeam.

    Primary channel URL: https://meshtastic.org/e/#Ci4SIDHMn8GX074n_yIOik3-c1l9CccxXWCzyXimIvdZYcaQGgZmYW1pbHk6AgggEgoIAUADSAFQHmgB
    
    Complete URL (includes all channels): https://meshtastic.org/e/#Ci4SIDHMn8GX074n_yIOik3-c1l9CccxXWCzyXimIvdZYcaQGgZmYW1pbHk6AgggCikSIMOYnWI3socNXuYxy-RI40Lg8BB-oqmXJEm814GTUnxgGgVhZG1pbhIKCAFAA0gBUB5oAQ

    copy and paste the channel URL’s into your notes, for later.

    Now we move on to the hardware needed to turn this into a robust, long term outdoor repeater

    The RAK repeater is very tolerant to extreme temperatures but the li-ion battery is not so forgiving. It is sensitive to very hot and cold conditions. The most limiting factor is charging li-ion in freezing conditions. This will quickly destroy a battery. To help minimize temperature swings I opted for a larger container with some insulation to smooth out the hot and cold transitions. This case was cheap, insulated and decent quality. So far its survived a few years in the harshest of conditions. https://www.harborfreight.com/brands/apache/1800-weatherproof-protective-case-small-black-64550.html

    This case is not enough to keep the battery above freezing. Winter months are long and very cold and my batteries would get trashed within a few months of use in winter conditions. To solve this problem I used a low temp-cutoff charge controller from adafruit. https://www.adafruit.com/product/4755 in conjunction with a 10k thermistor https://www.adafruit.com/product/372

    This charge controller is far superior to the internal charge controller of the RAK and with the added low temp cutoff I haven’t had to replace a battery since.

    == Roaming mobile nodes ==

    Requisites:

    – Small/portable
    – low power
    – battery powered
    – GPS
    – waterproof
    – low gain antenna
    – easily re-charged (usb)

    Materials:

    Lilygo TBeam v1.2 https://store.rokland.com/products/lilygo-ttgo-meshtastic-t-beam-v1-1-esp32-lora-915-mhz-wireless-module-wifi-gps-neo-6m-with-oled-display-soldered-for-arduino-q349

    cable gland pg9 https://www.amazon.com/dp/B07VT317NT

    39/64″ drill bit https://www.amazon.com/Drill-America-High-Speed-Reduced-Shank-64/dp/B01BKTNHPY/

    Pelican 1010 micro enclosure https://www.pelican.com/us/en/product/cases/micro/1010

    TO BE CONTINUED…