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They're actually new LoRa devices that look like the old Blackberry's.

"T-Deck is a pocket-sized gadget with a 2.8-inch, 320 x 240 pixel IPS LCD display, a mini keyboard, and an ESP32 dual-core processor. While it's not exactly a smartphone, you can use your programming knowledge to turn it into a standalone messaging device, or coding software."

When I was in radio school we cut a removed from service co linear antenna in half.
I was surprised when I seen how simple the innards were.
These type of antennae are usually vertical polarized and depending on the number of sections, can really squeeze the pattern flat to the horizon with resulting gain.
This PDF has a simple design using sections of coax soldered together in an alternating fashion.

73
Mike N0QBH

It was fun texting back & forth with two of these devices at the meeting.

Introduction

Meshtastic? is a project that enables you to use inexpensive LoRa radios as a long range off-grid communication platform in areas without existing or reliable communications infrastructure. This project is 100% community driven and open source!

Features

• Long range ()
• No phone required for mesh communication
• Decentralized communication - no dedicated router required
• Encrypted communication
• Excellent battery life
• Send and receive text messages between members of the mesh
• Optional GPS based location features
• And more!

How it works

Meshtastic utilizes LoRa, a long-range radio protocol, which is widely accessible in most regions without the need for additional licenses or certifications, unlike HAM radio operations.

These radios are designed to rebroadcast messages they receive, forming a mesh network. This setup ensures that every group member, including those at the furthest distance, can receive messages. Depending on the settings employed, the Meshtastic mesh network can support up to 100 devices concurrently.

Additionally, Meshtastic radios can be paired with a single phone, allowing friends and family to send messages directly to your specific radio. It's important to note that each device is capable of supporting a connection from only one user at a time."

When you send a message on your Meshtastic companion app, it is relayed to the radio using Bluetooth, Wi-Fi/Ethernet or serial connection. That message is then broadcasted by the radio. If it hasn't received a confirmation from any other device after a certain timeout, it will retransmit the message up to three times.

When a receiving radio captures a packet, it checks to see if it has heard that message before. If it has it ignores the message. If it hasn't heard the message, it will rebroadcast it.

For each message a radio rebroadcasts, it marks the "hop limit" down by one. When a radio receives a packet with a hop limit of zero, it will not rebroadcast the message.

The radio will store a small amount of packets (around 30) in its memory for when it's not connected to a client app. If it's full, it will replace the oldest packets with newly incoming text messages only.

Because I want to power my Winlink station 100% solar/battery, I needed to test the BMAX on a varying DC voltage supply like it would see connected to the station battery.
I have a higher end adjustable power supply that is well suited for this purpose with limiting (in case my test goes south!) and to the milli Amp metering.
I tested over a 18 hour period starting at 12.8v which is the low end for the LiFEPO battery and 14.4v which is the charging cut off.
8 hours were at 13.8v which is the normal output of a Astron 12v power supply.
The mini pc was running Winlink and VARA and I would open web pages on the Internet to add load from time to time.
I noticed no unusual behavior or heating. The current draw profile averaged around 300 mA idling with Winlink and I could get it to draw over 1A by starting more programs, as expected.
Most time it took between 300-700 mA operating Winlink/VARA-FM, sending and receiving email.

In conclusion, I'm confident enough to run mine from either a HAM 13.8v power supply or a active solar system up to 14.4v.
Long term operation could say otherwise and I will blow my horn if I find that out.

73
Mike N0QBH

When starting a previously working VARA FM program attached to a Digirig interface I've often encountered no receive audio showing on the VU meter.
Before you go into Windows and start tweaking the audio settings...
Try clicking on the VARA settings tab and then the SoundCard button. While there insure the input and output are USB Audio device, they probably are.
Like magic, when you close the dialog box your audio is working!? You're welcome.?
I have no idea why, but, I've seen it work too many times to ignore.

73
Mike N0QBH

The training will be held at the Law Enforcement Center in the EOC (NOT AT RESCUE!). ? The address is 2201 23rd St NE, Willmar. ? West end of the building (opposite of the jail). ?

Hello members, the next quarterly meeting will be held on Tuesday, April 30th at 6:30 pm. The meeting location will be at the Kandiyohi Rescue Squad building 213 Lakeland Dr NE, Willmar, MN 56201
There will be a short presentation and discussion on Winlink and the Vara modems with a demonstration after the club business is handled.

Just a reminder for those that may be interested in this training.

I updated some things and added this to the Club's QRZ page.

?HAMSci amateur radio operator John Landrigan, KA4RXP will be operating Maritime Mobile off the Mazatlán, Mexico coast at the beginning of the total solar eclipse as it transits to the Maritime provinces of Canada.

The 2024 total solar eclipse will begin at the following UTC times on April 8, 2024:

• Partial eclipse: 15:42 UTC (11:42 AM EDT)
• Total eclipse: 16:38 UTC (12:38 PM EDT)
• Greatest eclipse: 18:17 UTC (2:17 PM EDT)
• Total eclipse end: 19:55 UTC (3:55 PM EDT

The maximum eclipse will be at 12:17:19 local time and totality duration will be 4m 29s.

The HamSci organization is seeking to measure and record the ionospheric radio propagations that are influenced by this solar event.

In order to do so, KA4RXP/MM will be operating as a special event station, seeking your signal reports from all locations, especially in the 70-mile-wide path of the eclipse, during this rapidly changing ionospheric propagation spectacle. To maintain a sense of continuity, all radio activity will be confined to the 20-meter Amateur Radio band at approximately 14.265 MHz.

Just a simple signal report and Maidenhead Grid Square location is all that’s requested. The data will then be collated and analysis of the signal reports and their locations will be done in the post Eclipse interval. The station will be operating with 100 Watts of RF power and recording the entire session to make a continuous log, keeping details as seamless as possible.

Contact via?ka4rxp@...

The proposal you made about switching the 400' station seems like a logical choice.

I couldn't resist posting on Leap Year Day (Feb 29).?
All? the kids born today who only get a birthday every 4 years.
I'll bet somewhere, for only $19/mo you can ease their suffering!

This nice weather has me thinking of Spring fox hunting...I've only done it once, but, I had fun and would like to do it again.

73's
Mike N0QBH

The local Winlink gateway has been on line for several days as I type this and it has been working well.
I have been sending and receiving my Ham radio related emails in this manner and in the process, learning the ropes of operation.
Presently, the only connections are VARA FM mode on 145.070 MHz. Ben tells me 1200 baud packet access will be added on the same frequency.
Winlink packet is not quite the same as regular packet, but it uses the same hardware and can digipeat thru packet nodes to another Winlink station.

Which brings us to "How do I do get and use Winlink?"
You need a Windows 10 or newer computer to use Winlink and VARA.



The two programs are Winlink Express set up in the user programs area and you want VARA FM set up in the VARA products subdirectory.

Both programs download as zip files. I recommend extracting while still in the downloads directory.
The unpacked result is a installer program .
The Winlink program will want to install in the root directory. Use it's recommendation.
I learned the hard way that programs I installed in the program files directories are in protected memory.
Windows won't let anything write in there, meaning saving configs that normally live with the program don't happen.

To use Winlink you have to be registered (free). You register from within the Winlink Express program.
It involves giving your valid callsign as your user name and you chose a recovery password.
Then, assuming you have Internet, it will Telnet your application into headquarters and you are set.

You will need a software modem to let Winlink communicate via radio. Around here VARA FM is the best method.
VARA FM is downloaded and treated the same as Winlink - unzip and install it where it wants to go.
You will need to run the installer as administrator (right click mouse) and select that option.

Next, is determining how to connect the radio to the computer. There are several ways, I've tried many of them.
Digirig is far in a way my favorite. Small, inexpensive ($50) and a great selection of cables for oodles of different radios, all under $30 ea.



USB soundcards can be intimidating to set up. Digirig's audio is "plug n play" - no drivers.

The serial side is apt to need a driver download. Silicone Labs CP210x Universal Windows driver is what you will need.
The install page on the Digirig web site shows how to install the new driver, if needed. It's important as it controls the PTT of the radio.
It's a good resource and I recommend reading it first.



Once you have your Winlink VARA FM station all talking to and hearing the radio, you will need to make a note of what USB port on the computer you are using.
To keep life simple, always use that same port. If it isn't possible, you may need to reload the USB driver to the new port in order for the serial PTT to function.
Another thing I've noticed with Windows and USB just seems to take time, sometimes :) Step away and have a cup of coffee and sometimes you'll return to working drivers.

The last two steps before attempting a Winlink connection is to calibrate the audio levels in and out of the radio.
Pretty easy usually.
With the VARA FM program itself running, insure the squelch is open if you don't see any movement of the VU meter on the dashboard display.
If your radio uses a RX data connection in the back, you only need to adjust the USB Soundcard mic in levels to get the VARA VU meter needle to the 2 O'clock position.
If you had to open the squelch, you will also need to adjust the volume and USB Soundcard mic in to get the VU to the 2 O'clock level.
This is because that audio is coming from the speaker.

Setting the transmit audio level is done with another VARA FM station using the Auto tune function found in the VARA FM program soundcard button.
Your frequency must be the same as the other station, around here we are using 145.07 MHz for VARA FM. 
When you start auto tune, your station will send a series of 10 tones at gradually louder levels. If the other station hears you, it answers back with a pass or fail and tells you what to adjust.
It also sets the slider level in the auto tune display. Note, this adjustment is in series with the USB Soundcard Speakers (Digirig out to the mic) Windows slider.
We normally use W0AYE-10 as the other station since it's who we'll usually be connecting to and it's a known good signal.

That's all for this segment, next one will focus on operation.

One of the best places for Winlink info is it's HELP menu.? I will try to be available to talk someone thru installation and am usually listening on the 444.8 machine.
Else try n0qbh@...

73
Mike N0QBH