Enclosures for electronics and RF

Investigations into using ABS, polycarbonate and sheet metal enclosures to house electronics with a focus on getting that radio signal (wifi, 3G/4G) out of the box Requirements Weatherproof. IP66 = no dust and no water even from jets. IP55 would be okay […]

Robustel 3G Router Setup

Setting up a R1510-4L 3G router in Australia The setup is R1510-4L router with Telstra SIM card and Jasper web control. The goal is to setup the router on 3G and configure data allowances, etc. Plug into a computer and login to […]

OpenVPN for IoT

Using a AWS Linux server, and Raspberry Pi, Ubuntu or Robustel router clients Situation Lots of linux devices (and embedded devices) behind firewalls without public IP address Publicly accessible computer (AWS) Goals Connect from the server (or office PC) to these devices […]

linux commands

Test OpenVPN server on it’s standard UDP port telnet is so 2020 so use nc which does UDP too -v verbose -z test daemon -u UDP

Solar PV, Batteries and … Maths

Some, it all seems pretty simple, right? It’s just import, export, consumption. This post clarifies the sign (+ or -) conventions I use which seem to make things easiest. Each of the three images has a ‘control volume’ where we measure power […]

Debugging Pi from VSCode

There’s a few tutorials and references for debugging a python program on a remote (e.g. pi) computer. I had to fiddle a fair bit to get VSCode, ssh and debugpy to work. Here is how. Traps and Notes ptvsd is depreceated run […]

Backup and Restore SD Cards using linux

Once a Pi is setup, it’s useful to clone the SD card and save the state. Here’s how. See more details on losetup too. But wait! Is it exactly the same on a different machine? No! Change the cloned Pi a bit: […]

Insulating a Queenslander

Stud Walls Often you can’t access the wall without removing weatherboard or plaster. However, the stud bays in my house are open – no noggings, few wires. Therefore I’ll try to pump in insulation via (1) top (2) bottom or (3) a […]

Big Pete and The Champ

Big Pete Pre made wort: 1/2 whiskey wort, 1/2 smoked porter Dry malt: dark, 1kg Yeast: Belgium yeast 2 week ferment Dextrose: 70g Tastes ok on bottling. The Champ Pre made wort: 1/2 whiskey wort, 1/2 smoked porter Belgium yeast Primary ferment […]

Zinken Compact 21 : Repairs

I bought this unit in Brisbane, Australia. This records details in case they are useful to others. Bearings Bearings were mostly stuffed after 30 years. They are metric and available from standard suppliers. Steel sides (ZZ). Spindle Molder Belt Idler: 6000 (x2) […]