Oliver Sedlacek

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Oliver Sedlacek

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  • 09.12.2016
  • The gap between renewable energy promises and reality
  • The solar panels on my roof manage about 20% efficiency through to the grid, so I would say 70W/m2 is practical. With the total area of the earth being around 0.13 Pm2, we are looking at 9PW of available solar power. The IEA estimates global demand at 13TW, so a rough estimate comes in at needing to cover only 0.15% of the planet in solar panels. You could hide that much in the Sahara desert without anyone noticing.
  • 02.24.2016
  • Is rigorous engineering support dead?
  • Sadly I completely sympathise with your experiences. Engineering time is expensive, and companies seem to think it can't be squandered on interactions with customers.
  • 02.10.2016
  • Do grandmas make the best engineers?
  • Maybe we need to start a 'Hall of shame' for all products that really, really shouldn't be flawed in this day and age. Today's nomination is a toothpaste tube. Yes, really, you can mess up a toothpaste tube. The one I have in mind is too torsionally flexible, so when you try and open it the tube twists instead of the cap unscrewing. The only solution is to squeeze the tube quite tightly so that the pressure of the contents stiffens the tube, but guess what happens when the cap clicks open?
  • 12.22.2015
  • Reduce relay coil current with a reset controller IC
  • Nice idea, and very timely! I would definitely use the same transistor type for 'pull-in' and 'hold' to keep my BOM line count down. Digital transistors still tend to be cheaper than MOSFETs, so I might investigate them for this application.
  • 12.18.2015
  • Audio evaluation & measurement: A sense of perspective
  • As a professional analogue electronics engineer and an amateur HiFi builder, I'm fascinated by the relationship between quantifiable deficiencies and perceived audio quality. A system may have impressive THD, SNR and bandwidth, and may still sound disappointing. I don't claim to have golden ears, but I find sound differences easy to pick out, as do press-ganged friends, so over the years I've come to the conclusion that the favoured metrics are pretty useless. As to the subject of what to measure, clipping behaviour seems to matter greatly, as do the properties of any energy storage elements (capacitors, inductors, voicecoils) in the signal chain.
  • 11.08.2015
  • What's a stereo system, anyway?
  • I don't listen to as much music as I used to, but I've recently got my record deck overhauled and I've been playing my vinyl again. Hifi is what got me into electronics all those years ago, and I still build my own amplifiers and speakers. I've come to the conclusion that you either listen to the music, or you listen to the Hifi. If the Hifi is really good, you can stop listening to it and enjoy the music.
  • 06.29.2015
  • Keeping smart lamps “Energy-Efficiency Smart”
  • I'm depressingly unsurprised by this story. The LED manufacturers are producing some really impressive LEDs, but what the consumer gets is very disappointing. I've been hoping to cut my electricity bills at home (and keep the house cooler in the hot weather), but I still can't easily buy quality LED lamps to suit my needs.