It’s been a crazy run, trying to make this happen. After less then one month I now have the first functional hardware iteration or the first prototype. The Portable Environmental Monitor has been brought to life! All that’s left is finalising the enclosure (it will be a nice rugged aluminium enclosure, small enough to fit the palm of the hand, despite the many sensors packed inside) and the software (both the firmware and the server side for centralising data sent via the esp8266 module). Then there are the small improvements, part of every product’s path.

There were a few issues like regulator getting a little too hot, unhappy to have a boost converter as a neighbour, or a wire that had to be cut, because I forgot to design a diode in place to stop the battery driven inverter from charging the battery. Well, these things happen, the fix was easy, and didn’t even damage the PCB:

To comply with Stage 2 requirements of the Hackaday Prize competition, I had to shoot a 2 minutes video, and this was an excellent choice to present the prototype in its current form, and to iterate a few of its construction details:

The High voltage inverter is the one used in uRADMonitor model A, it is a very compact design that I came up with last year. It was initially designed for a 400V output, as needed for the Russian Geiger tubes, but this time it will be used with the LND712 that requires 450V – 500V to run. The inverter is capable of delivering that as well, just by setting the voltage output level in the software. Here are a few tests to identify the best frequency for the PWM signal: