Do Nothing  Box v2.0 

12/13/2023

This is what happens when you’re retired and run out of projects.

You build something useless that does nothing….

While rummaging through my various parts collections I found a really old meter. 

A web search identified is as a part to a military radio transmitter.

Since I had no such transmitter I needed to do “something” with it.

This reminded me of my original Do Nothing Box that I gave away so I thought 

“why not build another one?” 

More searching through my parts collections turned up all the components needed.

Except of course some kind of box. (can’t have a do-nothing box without a box).

I gathered up all the parts and started to build using a cardboard box surrogate.

Once everything seemed to be working as expected I had a pretty good idea of what the final 

dimensions needed to be and selected some bits of wood to construct the final enclosure.

My woodworking skills are mediocre at best but I took my time and was quite pleased with the results.

Until I tried to stain & finish it.  The staining came of a bit blotchy so I was disappointed there. 

However the messy stain gave it sort of an “old-timey” look that matched the old meter.

The components consist of the old meter of course which is surrounded by 6 addressable RBG LEDs.

The speaker assembly is something pulled from an old LCD TV set (has really nice sound).

The CPU module is part of an EWPlus 971 refrigeration controller (similar to this).
This version has an Atmel ATMega16 processor and the board it’s on has a 5VDC regulator and a few driver transistors

 I could make use of, so I put the whole thing inside the box. (the display and buttons are not really used).

I built a small connector board to hold the CPU module, a relay and a few other connectors.

Additionally there’s a couple of 3.6v Li-Ion cells from an old laptop battery pack, an RC Servo motor and of course a big, vintage looking, toggle switch.

I used my 3-D printer to print the actuator arm attached to the servo motor, the "On" nameplate that hides the hole for the actuator arm
and various mounting brackets as well as a couple of thin, semi-transparent white rings to cover the LEDs.

(all this stuff is shown in the photos below)

Then I spent several days tweaking the software and display & sound sequences.

I had a bit of trouble with the power draw when the servo was activated so I had to make sure the LEDs 

were off until it got moving. 

Unfortunately the video attached doesn’t show the colors of the LEDs very well. 

Now this box sits on a coffee table in our living waiting for an unsuspecting guest to ask what it does….

Description of download links:
DoNothingBox1.zip Source Code
DoNothingBox._Movie.mp4 Link to Video
DoNothingBoxV2.pdf   Schematic