Another small step

I decided that I’d finish last night on a high by adding the external connections to my little microelectronic device that I made to control my Savannah’s hour meter. I finished the basic device a few days ago and all that was needed to connect it to the outside world was a set of flying leads, for the 12V power and earth, the input from the rev counter and the output to the earth of the hour meter. Here’s how it looked once I was done.

So all ready to give it its first test by connecting it for the first time to a 12V power supply. I didn’t know what to expect but my initial hope was that it wouldn’t start smoking and fry itself because I’d made some stupid error when I worked out all of its connections and its layout on the copper strip board. Anything else I thought would be a bonus, so I approached connecting the 12V power and earth to a battery with some trepidation. Here’s what happened.

It turned out that I needn’t have worried at all. All that happened was a lttle red light illuminated on the Arduino microprocessor and everything else stayed cool and calm, including myself. Obviously I won’t know that it’s actually doing the job that it’s intended for until I finally connect it up but it’s a big relief to know for now that nothing seems to be amiss with it.

But more seriously, it doesn’t appear at this stage as though it’ll be a source of danger, which is always the worry when you introduce a strange electronic device into an aircraft with its potential for shorting and causing a fire, especially when it’s going to be installed in an inaccessible place where it won’t be visible. However, I’ll continue to keep my guard up until it’s actually fitted, I’ve run the engine and it’s proven to be working correctly.