Michael Dunn

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Editor in chief

Michael Dunn is editor-in-chief of EDN, and has been messing with electronics almost as long as he's been walking. He got his first scope around age 15, and things have been going downhill ever since. Scopes now vie with wine racks, harpsichords, calculators, and 19th century pianos for space. Over the years, he's designed for the automotive, medical, industrial, communications, and consumer industries, as both freelancer and employee, working with analog, digital, micros, and software. Since 2000, he's run the TekScopes Yahoogroup, now with over 5,000 members. He was previously editor-in-chief of Scope Junction: http://edn.com/collections/4422580/Scope-Junction-blogs


Michael Dunn

's contributions
  • 05.01.2017
  • 4 Comment(s)
Hubsan FPV drone teardown
  • 04.26.2017
  • 12 Comment(s)
Neutral woes
  • 04.03.2017
  • 10 Comment(s)
I Sing the Capacitor Electric
  • 03.01.2017
  • 15 Comment(s)
Grammar and the engineer
  • 01.25.2017
  • 5 Comment(s)
VoIP phone teardown
  • 12.21.2016
  • 3 Comment(s)
Talking about Design Ideas
  • 04.26.2017
  • Neutral woes
  • Three-phase to the home?!? That's something I've never heard of. Interesting... But correct, this is "two-phase". The transformer primary is fed by 7.2kV and earth ground. Ground is connected by wire, but as demonstrated in my previous blog, there's enough earth conductivity for the system to mostly work even when the wire is broken. The secondary is 240 VCT, giving two 120V legs. The centre-tap is earth-grounded at both the transformer and panel end. It doubles as neutral and earth ground, hence needing to be physically earthed close to the panel so the ground can't lift in the presence of neutral current or a fault.
  • 04.26.2017
  • Neutral woes
  • Interesting, thanks. The "clipped" waveform is certainly consistent with poor power factor (no PFC) devices drawing high currents at the peaks, but the waveshape doesn't really change under different loadings. I may yet try absolutely zero (0) loading...turn EVERYTHING off (except the scope...and I'll measure the other side of the line!), but I'm pretty certain the distortion is from the "grid".
  • 04.10.1997
  • Analog multipliers take cube root
  • The online version here is probably not directly recoverable, but amazingly, I do have the print version! I'll restore this when I have some time, so check back on occasion.
  • 05.02.2017
  • Pebble Time Round vs Moto 360: face off
  • Seriously, thanks for being a loyal reader. Newsletters and/or the RSS feed are good ways to catch the latest content. (though sadly there is a temporary problem that's making it impossible to control newsletter subscriptions) Most of your comments seem negative. Perhaps I've misunderstood them. (though we've no problem with constructive criticism! which I guess is what this one is ;-)
  • 05.01.2017
  • SEPIC/Ćuk converter sprouts second output
  • Hmm, they look fine to me. Ah, I think I understand the problem: They look fine on a double-res (e.g., "Retina") display, but not so great on a regular screen. Although the images are not linked to larger versions, they are themselves larger than they appear in-article. Just open them in their own tab and they should look fine. Images with fine lines like these may be one place where smaller native resolution is better... I'll see if I can improve them.