Back in the late 80’s I built a kit that is a reminder for taking out the garbage. It was an interesting project that I originally built as a reminder to take tablets, although since then it has been mostly used as a garbage reminder. This a picture of it in the original plans.
While the project in the article had a square button and a graphic on the box, mine just had a single push button, a separate LED and looked more like “the internet” from the IT Crowd.
I’ve only recently stopped using it after over 30 years and have probably only changed the two AA batteries a couple of times, so it seems the be a very efficient device.
It has very basic controls. A single LED flashes on the days that it is set. A bank of dip switches to set the days of the week that it was to display the alert. The timer starts an alert at the time batteries are installed, so if you want the timer to go off at a set time, simply install the batteries at that time. On garbage day the LED flashes until the push button is pressed or for 7 hours and 12 minutes if the button is not pressed.
I recently had a look online to try and find out some more info about the project. It was published in Silicon chip August 1989. The author was Johnno “Blue Singlet” Clarke. The about page for Silicon Chip includes a John Clarke and there is an incredibly impressive list of projects and articles by that John starting with the first issue of the magazine right up to the current one, but this project is not listed in that search. If it is the same person, there must be a story with his name for this project.
It uses a 32.768kHz crystal to generate the timing and then uses a number of digital ICs. It looks like it would have taken quite a lot of thought to design it.
I don’t have much more to share about this project, but it is one of the most used kits I have built. I thought someone may enjoy a few images of it. Thanks John. It’s been a useful project.
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