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Just reconfigured my home network to separate my WiFi and isolate IoT devices on a separate subnet. Hit some unexpected roadblocks – documenting them here before I forget:

1. Alta Labs ROUTE10 Surprise
Turns out this runs OpenWRT under the hood. All standard uci commands work, but persistence requires writing them into a post boot shell script located at /cfg/post-cfg.sh.

2. Ubiquiti USG NAT Limitations
The USG series has some annoying constraints:

• No true non-NAT “External Zone” support
• Can’t fully remove stock NAT rules
• Workaround: Create NAT exclusion rules instead

When creating a 128/256-bit PSK that starts with a specific base64 prefix, you might notice the prefix changes after encoding. For example, you set your key to start with ABCDPSK, but the encoded string shows ABCDPSL or something else instead.

Only today I realized that Base64 encoding works in groups of 3 bytes (24 bits), which translates to 4 base64 characters. If your prefix length isn’t a multiple of 4 characters, the encoding can “roll over” when random bytes are appended, shifting the bits and changing the prefix characters.

Below is my workaround:

• Choose a prefix with length divisible by 4 (e.g., 4, 8, 12, 16 characters).
• Decode this prefix to raw bytes.
• Fix these bytes at the start of your PSK.
• Append random bytes to complete 32 bytes (256 bits).
• Encode the full key to base64.

This way, the base64 string will start exactly with your chosen prefix without rollover.

TLDR: Fix your prefix length to multiples of 4 base64 chars to ensure your key starts exactly as expected. Understanding base64 encoding basics can save you trouble when generating keys.

TLDR: Get your antenna from reputable vendor, beware of replica/fakes too.

Turns out most of the budget antennas are replicas. They kinda work, just poorly. Without a VNA, you wouldn’t even know – you’d just waste time wondering why your range sucks.

The replicas aren’t completely fake (they do function), but:

• Gain ratings are inflated
• Build quality is questionable
• Performance is inconsistent

If you’re serious about RF:

1. Pay for legit antennas from known brands
2. Or at least test your cheap ones properly

Otherwise you’ll spend more time debugging than actually using the damn things.

Initially I thought the antenna I have gotten is faulty, so I got myself a replacement when I purchase another T-Deck Plus and realized that the antenna that ships with the T-Echo is total shit.

Apparently, how each device identifies its own coordinates depends heavily on the precision level set for the primary channel. So, if you are on an expedition or require multiple nodes to synchronise high-precision coordinates, the only current method appears to be configuring your private channel as the primary channel.

After that, create a LongFast channel and manually set the frequency slot, since slot 0 will automatically change if you modify the primary channel. In my case, I had to set it to frequency slot 4 on SG_923.

TLDR: Meshtastic uses the coordinates of your primary channel as a reference. If you are new to Meshtastic and suspect your GPS is faulty, it is likely due to the precision level setting