David_Ashton_EC

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David_Ashton_EC

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  • 10.02.2017
  • They're still selling incandescent flashlights?
  • Bill.... maybe true... but in the solar garden lights the rechargeables are needed, so why not connect them in the most reliable way possible? To sell more of them? I make a point of not re-buying types that let me down. Re flashlights (sorry, I'm British so I call them torches) you're right. I went to a lot of trouble to make mine rechargeable, but if anyone stole it I guarantee they'd chuck the battery out when it went flat and buy a new one. So much for sustainablity... :-)
  • 10.02.2017
  • They're still selling incandescent flashlights?
  • One disadvantage I have found with LED flashlights is that the beam is usually very narrow. Useful if you're trying to illuminate something specific but not if you are trying to scan an area looking for something. Some time ago I lost my car keys while walking my dogs and failed to find them with my LED torch. The next morning in daylight I found them in about a minute. My wonder is not that they don't make more LED torches, but that they don't make more rechargeable ones. I made one I bought rechargeable, story here https://www.eetimes.com/author.asp?section_id=30&doc_id=1319957 I suppose the reason is that eventually the rechargeables would fail or lose capacity, and 99% of the great unwashed would then just chuck them out, Although even this would save some landfill. The place I walk my dogs is a graveyard, and people often put solar garden lights by their beloveds' graves. They fail and they chuck them in the bins where they are retrieved by yours truly. In most cases all it needs is a twist of the battery to remake corroded connections and they're fine again for another year or so. One wonders why they don't use tagged, soldered batteries in these things.
  • 12.05.2016
  • Why are these LED aisle lights being pulsed?
  • An easier method (given that there are probably lots of LEDs to play with) would be to put 2 LEDs in antiphase parallel, then put lots of those in series, with one resistor to limit current to the whole string so that it will work off 110VAC. Each LED will limit the reverse voltage seen by its mate. And only one resistor to rule them all :-)
  • 10.10.2016
  • Incandescent lamps and service life
  • I had a set of decorative wicker lampshades I bought in Madagascar years ago. I fitted them with lampholders and 40W clear bulbs and they gave a very nice effect. In my first house I had them on a dimmer and you could not switch them on at full brightness, you had to bring them up with the dimmer. The bulbs lasted the entire time I was in that house (~10 years) without any replacements. In my current house they are on a 2-way switch with a dimmer so it is possible to switch them on at full brightness. I reckon in the 12+ years we've been here, I've replaced 10 or more bulbs. So Antedeluvian, there's a possible solution for you....
  • 06.14.2016
  • NASA Space Station’s top 10 benefits to humanity
  • Thanks for that Steve. I recently wrote about seeing the ISS for the first time here http://www.embedded.com/electronics-blogs/embedded-down-under/4441170/Keeping-an-eye-on-the-International-Space-Station and some people (not least my wife) have expressed the sentiment "what's the point of spending all that money?" It's fairly easy to counter, but this gives me some additional ammunition. One small criticism, your screen shots are just photos of screen images, they'd be of far better quality if you had taken screen captures with the PrtScrn key, then pasted into Paint or similar to save them. Or just provide links to the pages with each pic. Incidentally our blogger Aubrey Kagan did an article on his work on the Canadarm 2 - it is here http://www.eetimes.com/author.asp?section_id=28&doc_id=1328685