Comments on: Ground Loop Tutorial

By: Tomi Engdahl

Tomi Engdahl — Mon, 22 Aug 2016 17:58:01 +0000

Ground Loops and Hum
https://www.youtube.com/watch?v=GS-6jBk9YPM

How Ground Loops happen and how to avoid them.

By: Tomi Engdahl

Tomi Engdahl — Fri, 19 Dec 2014 09:41:23 +0000

The myth called “ground”
http://www.edn.com/electronics-blogs/test-voices/4437985/The-myth-called–ground-?_mc=NL_EDN_EDT_EDN_today_20141218&cid=NL_EDN_EDT_EDN_today_20141218&elq=2c0040928de34be4b9f2bf91178fe23a&elqCampaignId=20789

A friend of mine told me years ago that there’s no such thing as voltage. This was a real shock to me, because I had a voltmeter in the lab. He explained that Maxwell’s equations, which are accepted as the basis for all electromagnetic (and therefore circuit) theory, include current, electric field, and magnetic field, but no voltage.

Most PCB designers talk about things such as DC supply voltage or a signal voltage on traces. If I bring up the idea of current flow, they will accept it. Then we discuss how the return current always flows back to its source on ground.

The term “ground” is probably the most misunderstood and misused term in electrical engineering. I blame the universities. They start their electrical engineering instruction with DC circuits and then progress to AC circuits with resistors, inductors, and capacitors. But the ideas of parasitic and nonschematic effects are seldom discussed in classes. Usually, lab assignments are relatively low-frequency projects, probably designed to ensure parasitic effects aren’t encountered.

We learn to read schematics with this magical return current path called ground. At low frequencies, the physical distance between the ground connections is electrically small. This concept of having all ground nodes connected at the same point is reasonable.

In the real world of high-speed circuit boards, the physical distance between ground node connections isn’t electrically small, so the distance between the nodes becomes meaningful. Current must travel some distance to return to its starting point. This distance can adds losses that make ground something else entirely.

By: Tomi Engdahl

Tomi Engdahl — Fri, 05 Sep 2014 07:47:04 +0000

The G word: How to get your audio off the ground (Part 2)
http://www.edn-europe.com/en/the-g-word-how-to-get-your-audio-off-the-ground-part-2.html?cmp_id=7&news_id=10004694&vID=209#.VAlpK2NsUik

Audio signals are voltages. A voltage is the potential difference developed between two points. We grab a voltmeter and connect the two test leads to probe the two points, or “nodes” that we want to know the potential difference between. The author continues his quest to apply this principle to removing “Gnd-think” from audio circuit layouts.

By: Tomi Engdahl

Tomi Engdahl — Fri, 05 Sep 2014 07:46:27 +0000

The G word: How to get your audio off the ground
http://www.edn-europe.com/en/the-g-word-how-to-get-your-audio-off-the-ground.html?cmp_id=7&news_id=10004372&vID=1320#.VAlqB2NsUik

By: Milla

Milla — Sat, 05 Oct 2013 17:39:26 +0000

Good response in return of this question with genuine arguments and describing everything about that. Also visit my homepage: mom (Milla)

By: kdc minh son q9

kdc minh son q9 — Wed, 18 Sep 2013 03:29:02 +0000

You really make it appear so easy with your presentation however I in finding this topic to be really one thing that I think I would never understand. It seems too complicated and extremely huge for me. I am taking a look ahead to your subsequent post, I will attempt to get the cling of it!

By: natural solutions

natural solutions — Wed, 19 Jun 2013 15:01:05 +0000

I’m gone to say to my little brother, that he should also pay a visit this web site on regular basis to get updated from newest news.

By: polycystic ovarian syndrome diet

polycystic ovarian syndrome diet — Wed, 19 Jun 2013 13:16:34 +0000

Hmm is anyone else encountering problems with the images on this blog loading?
I’m trying to figure out if its a problem on my end or if it’s
the blog. Any suggestions would be greatly appreciated.