Michael Dunn

's profile
image
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
  • 04.18.2017
  • Audio levels, dBu, dBV, and the gang: What you need to know
  • So, what, you're pitting one Wpdia entry against *another* Wpdia entry? Great. How about providing a primary reference? Here are a couple of NON-Wpdia quotes: "The origin of the index of dBu comes from "u = unloaded" and dBV comes from "V = 1 volt". Some say: The "u" in dBu implies that the load impedance is unspecified, unterminated, and is likely to be high" "dBu represents the level compared to 0.775 Volts RMS with an unloaded, open circuit, source (u = unloaded)." from: http://www.sengpielaudio.com/calculator-db-volt.htm and http://www.jimprice.com/prosound/db.htm respectively.
  • 06.27.2011
  • Technique trims op-amp amplifiers for low phase shift
  • My previous phono preamp employed a similar idea – a "supermatch" LM394 bipolar pair connected to offset terminals (of a 318? maybe). Can't definitely remember the source, but most likely a National appnote!
  • 11.15.2014
  • Understanding isolated DC/DC converter voltage regulation
  • Yes, that's a confusingly drawn "block diagram". I think the main transformer is meant to be in the "Isolated DC-DC power stage", and the "transformer" block should be seen as a feedback winding on the main... Don't take the connections literally.
  • 04.03.2017
  • I Sing the Capacitor Electric
  • To clarify, the capacitor buzz was definitely caused by the heat-pump. The cap fell silent when I opened the HP breaker.
  • 04.03.2017
  • I Sing the Capacitor Electric
  • Yes, I'll mount the caps in their enclosure with silicone marmalade, and drizzle some over them. I'm too cheap to pot the whole box. Reminds me of some power toroids I've used. They hum a bit (tho less than the equivalent standard core), but when I switched to epoxy-potted donut holes, they fell silent.
  • 04.03.2017
  • I Sing the Capacitor Electric
  • I'm a bit worried that six parallel caps may draw such a surge that it will be difficult to close the breaker! I was also concerned about pitting the breaker contacts, but hey...they're made to operate into a dead short without failing, so that shouldn't be an issue.
  • 04.03.2017
  • I Sing the Capacitor Electric
  • Ha, cool – that would make a great Design Idea :-) Reminds me of the automotive phase of my career, and switching 10-20A currents. Energizing the circuit would cause my heavy hookup wires to convulse.