Many many years ago I started experimenting with some simple electronic circuits and needed one 9V DC power supply. I already had the transformer and my father gave me a couple of diodes and one electrolytic capacitor. "Piece of cake", I thought.
During first power-up the diode emmited light, the diode I used had a small glass window in the anode lead, "that should be normal, that's what the glass window is for" I thought (again). But after the second power-up, when I was goind to meassure the output voltage the diode exploded.
A-ha! I connected the diode, the transformer and diode... IN PARALLEL! Probably that was the first LED ever ;), at the first for me.
I also had a weird problem once - intermittent failures / garbled characters on a printer belonging to British Airways in an airport office. It always worked fine when a tech was there! Symptoms were like a bad data link, but this was connected with about 15 feet of cable. Or so we thought. Eventually I decided to see if the cable had been chewed by rats or something. What I found was an inline connector in the middle of the cable (original cable was not long enough to reach the 15 feet) hidden behind a desk. And ants had made a nest in the shells of the 25-way D connectors. A-HA! Ants produce formic acid which had obviously caused some partial shorts. Cleaned the plugs up, put some bits of mothballs inside them and never had another problem. Moral of story: always expect the unexpected!
A number of years ago I was working as a computer field service tech. As many of you probably realize, one of out biggest headaches was intermittant failures that couldn't be duplicated. I began receiving calls every afternoon near quitting time regarding a printer spewing out paper uncontrolably. I would drive to the site, annoying my wife by missing dinner, only to find the problem had vanished and could not be duplicated. The calls continued almost, but not completely, daily. In desperation, I began changing components, beginning with the most likely ones, but no luck. The calls continued to come in nearly every afternoon. Finally, one Monday, I got the same complaint, but an hour earlier than previous. This was my A-Ha moment. Daylight savings time had just ended, The next day I visited the site a bit before the problem had been expeienced and watched the sun, shining through a nearby window illuminate the printer and activate a paper sensing photocell. Drawing the blinds resolved my headache and restored my reputation.
MeasurementBlues, thanks for the tip on how to embed a video. I did not realize it could be done here. And I'm glad you liked the video. It's one of my favorite songs of the 80's, though I have lots of favorites from that decade--there was certainly a mind-boggling abundance of creativity and stellar musicianship and vocal talent.
This thread brings me back to my highschool advanced algebra class. I had decided to risk taking the accelerated class. The first week was spent studying groups and fields, which really stretched my mind in a painful way, as I had no prior knowledge of either, nor were they even mentioned in the textbook we were using, and then I got back my first test with the score of a....36 out of 100. Yikes. I was pretty demoralized, but it turned out to be a B- on that particular grading curve. Needless to say, there were lots of a-ha moments that year after that first uh-oh.
One of the struggles with any field of study is learning the vocabulary, and why certain vocabulary is chosen to implement certain concepts (like the words permittivity and permeability). I also use to build Radio Shack projects, and remember as a kid being explained the concept of "ground" but not fully grasping it at the time. Huh? Ground? It's an electronic term? Some a-ha moments take a little foundation laying, and as they say, learning is a lifelong process!
Thanks Martin, the good old RTFM Technique, huh? I found when I tried I could not even get a graphic into the window, let alone post it, but I will experiment some more and let you know how I go. Meantime I have to get off to work :-((
@MB - it is a good video. But tell me, how do you put a picture in a comment.... can you??? I've tried and could not get it to work. The "Insert Image" icon in the editing screen only lets you insert an image from a URL - if you enter a file and path on your own hard drive it won't work?
NASA's Orion Flight Software Production Systems Manager Darrel G. Raines joins Planet Analog Editor Steve Taranovich and Embedded.com Editor Max Maxfield to talk about embedded flight software used in Orion Spacecraft, part of NASA's Mars mission. Live radio show and live chat. Get your questions ready.
Brought to you by