A Precision Zero Ohm Resistor - Page 1
Forum section: electronics / general

author: amspire
author_rank: Super Contributor
timestamp: November 20, 2011, 05:09:15 am
content: I guess there must be a real use for precision zero ohm resistors, but it just sounds stupid. Would you want to put it on your resume? A Zero Ohm Resistor Designer.http://www.ohm-labs.com/pdfs/resistance/100-0.pdfI have been looking for years to find a reference to check all those 0 ohm SMD chips against. Here it is!Funny. There is no percentage tolerance figure. 1% at least, surely!Richard

author: JonnyBoats
author_rank: Regular Contributor
timestamp: November 20, 2011, 05:30:24 am
content: Lets get a big box of 1% tolerance zero ohm resistors and see if they have a bell curve distribution centered at zero ohms or if the mean value is lower than the nominal valve as was the case for the resistors Dave tested.I could really use some of those zero ohm passive resistors with a value less than the nominal value

author: robrenz
author_rank: Super Contributor
timestamp: November 20, 2011, 05:50:50 am
content: Zero ohm smd resistors can be as high as 20 mOhm so they are far from zero.The percent error is easy 50 nanoOhm / 0 = infinity infinitely innacurate.So lets use 50 nanoOhm error on 1 nanoOhm (close to zero) = 5000% error50 nanoOhm error on 1 picoOhm (closer yet to zero) = 5000000% error

author: amspire
author_rank: Super Contributor
timestamp: November 20, 2011, 06:00:05 am
content: And you spend all that money thinking you are buying an everyday run-of-the-mill 50 nanoOhm resistors and it is a fake!It just fools a 4 wire ohms meter into thinking it is less that 50 nanoOhms. It actually will be somewhere in the microOhms at least.

author: Zad
author_rank: Super Contributor
timestamp: November 20, 2011, 11:41:20 pm
content: Recently I spent several days designing a zero-ohm active resistor, if that helps at all.

author: phil_jp1
author_rank: Regular Contributor
timestamp: November 21, 2011, 01:08:01 am
content: Quote from: Zad on November 20, 2011, 11:41:20 pmZero-ohm resistor it's great, but what about infinity resistance standard?How do you test your 8.5 digit meter for parasitic resistance between probe connectors?I feel, like I need to get down to work on that right away!

author: amspire
author_rank: Super Contributor
timestamp: November 21, 2011, 01:20:21 am
content: Quote from: phil_jp1 on November 21, 2011, 01:08:01 amI can see you dominating the market - I have never seen anyone else make precision infinity ohm resistors.There are all sorts of spinnoff's. Like the multiturn infinity ohms potentiometer. And dials that have every division marked as infinity.What sort of temperature coefficient do you think you can do?

author: ivan747
author_rank: Super Contributor
timestamp: November 21, 2011, 01:23:41 am
content: V = IR10 = I*010 = 0The resistor needs to have 0% accuracy, though.I wonder what are the effects of negative resistance.

author: amspire
author_rank: Super Contributor
timestamp: November 21, 2011, 01:47:21 am
content: I like the idea of a 10 decade resistor box with steps of infinity ohms. Regular calibration required at a price .. well .. how about make it infinite as well for neatness.I have actually seen it. I remember this guy who made these open ended copper coils to correct for "bad energy" that you mounted on something like a fence post.To "tune" the coils, he used a dowsing pendulum and a box he made full of rotary 10 position switches. I had a look inside, and each switch had a single wire going to it. He actually sincerely believed in what he was doing, and he was incredibly proud of his box.

author: phil_jp1
author_rank: Regular Contributor
timestamp: November 21, 2011, 02:03:35 am
content: Quote from: amspire on November 21, 2011, 01:47:21 amBut that's actually a real schematic to correct for "bad energy" and to tune that coils!It's just like an Ambient Field Conditionerhttp://www.lessloss.com/blackbody-p-200.htmlor Fostac Maximushttp://www.fostac-international.com/en/wissenswertes/maximus.htmlwhich:- Optimises the natural energy flow in buildings- Harmonises electro-smog- Repolarises water veins and other geopathic interference fields- Increases the efficiency of electricity and raises its effectivenessor maybe protection from "dirty electricity":http://youtu.be/MLOx1kWCWoc--But if to be serious, there's so many people who sincerely believe in such absurd stuff...

author: joelby
author_rank: Frequent Contributor
timestamp: November 21, 2011, 02:17:38 am
content: Quote from: ivan747 on November 21, 2011, 01:23:41 amYou can't buy a negative resistor, but some diodes exhibit negative resistance. Have a read ofhttp://en.wikipedia.org/wiki/Negative_resistance.

author: 8086
author_rank: Super Contributor
timestamp: November 21, 2011, 03:16:54 am
content: Quote from: ivan747 on November 21, 2011, 01:23:41 amCome on nowYou can't do that!

author: McMonster
author_rank: Frequent Contributor
timestamp: November 21, 2011, 04:09:36 am
content: Quote from: 8086 on November 21, 2011, 03:16:54 amIt reminds me of the old CS joke where 6 times 9 equals 42.