Hi everyone. I'm looking for some feedback and advice on my first self-build MeshCore repeater.

Objective

Build a reliable fixed MeshCore repeater (“Garviel Base”) using a Heltec WiFi LoRa 32 V4, with an EU868 antenna, USB mains power and a protected two-cell 18650 battery backup. I'd also like to leave the option of adding solar power later.

I'm documenting the build as I go because I've found it surprisingly difficult to find a complete step-by-step guide or video that takes you from a pile of components to a finished repeater.

As a beginner, even identifying some of the parts and knowing the terminology needed to ask the right questions has been a learning curve. Once I've finished and tested the build, I intend to tidy up the document and share it for anyone else starting from scratch.

Progress so far

The V4 is running MeshCore as a repeater and working from USB power.

I've built a 1S2P battery pack using two 18650 cells in a parallel holder, with a 1S BMS/protection board between the battery holder and the V4 battery connection. This was tested with a multimeter and succesfully connected to the device, the batteries needed chargingbefore I properly test USB → battery failover.

The external 868 MHz antenna bulkhead is also fitted to the enclosure and connected to the V4 by a short pigtail.

Questions I could use some help with

1. How would you mount the components inside the enclosure?

The V4 doesn't appear to have dedicated PCB mounting holes, so the nylon standoffs I bought aren't an obvious solution.

How are people securely mounting V4 boards? PCB cradle/edge clips, adhesive supports, a mounting plate, 3D-printed bracket, or something else?

I'd also like the battery holder and BMS to be properly secured with sensible strain relief rather than simply stuck into the box.

2. How small could I reasonably make the enclosure?

The enclosure I bought is enormous for what is actually going into it!

Once everything is positioned, I'm thinking the case only needs enough additional space for wiring, the antenna pigtail bend radius, ventilation/clearance and maintenance.

Is there a particular enclosure or approximate size that people have found works well for a V4 + 2×18650 setup?

3. What's the neatest way to get USB power through the enclosure?

I'd rather not cut a USB-plug-sized hole in an otherwise weather-resistant enclosure.

Would you use a cable gland with a captive USB cable, a waterproof panel-mount USB-C bulkhead/feed-through, or something else?

Ideally I want something weather resistant, mechanically secure and still reasonably easy to service.

4. How would you provide for solar later?

Solar isn't required for this first installation, but I'd like the design to accommodate it.

Would you add a second cable gland for the solar cable, use a waterproof panel connector, or approach it differently?

5. Insulating connections

What is the best way to protect bare electrical connections, in particular the battery protection ?

And finally...

Is there anything obviously wrong with the design so far, or anything you'd change before I go any further?

I'm particularly interested in battery safety/protection, power failover, RF/antenna layout, internal mounting, weatherproofing and anything experienced repeater builders know now that they wish they'd known on their first build.

Happy to share photos, wiring details and the parts I've used if that helps.

Thanks!

Edit: The batteries were flat on arrival, now they've charged I've tested failure over and the heltec continues working without mains usb.