But that's not a star ground!
HoJo is right that ground currents are important--he's just wrong about how they work and what to do about it.
Cheers
Phil Hobbs
-- Dr Philip C D Hobbs Principal Consultant ElectroOptical Innovations LLC / Hobbs ElectroOptics Optics, Electro-optics, Photonics, Analog Electronics Briarcliff Manor NY 10510 http://electrooptical.net http://hobbs-eo.com
Agreed, provided one has good wisdom (and instincts) for component placement.
Cheers
Phil Hobbs
-- Dr Philip C D Hobbs Principal Consultant ElectroOptical Innovations LLC / Hobbs ElectroOptics Optics, Electro-optics, Photonics, Analog Electronics Briarcliff Manor NY 10510 http://electrooptical.net http://hobbs-eo.com
Good IDCs displace the insulation entirely and just grip the wires. Grip varies fairly widely between types, as judged by how hard you have to crank the vise to seat them.
Which ones don't you like?
Cheers
Phil Hobbs
-- Dr Philip C D Hobbs Principal Consultant ElectroOptical Innovations LLC / Hobbs ElectroOptics Optics, Electro-optics, Photonics, Analog Electronics Briarcliff Manor NY 10510 http://electrooptical.net http://hobbs-eo.com
Depends on the metal and on the frequency. You can get that sort of behaviour in free-electron metals in the IR, but not in "normal conductors" at RF. In the high-conductivity limit the fields inside the conductor aren't oscillatory with depth but are modified Bessel functions. If that weren't so, there would be certain wire radii where the radial field went to zero at the surface, so you wouldn't be able to satisfy the patching conditions at the boundary unless the field outside were identically zero.
The tails of the fields interact in the middle, which makes the falloff much slower--the physics is basically the same as frustrated total internal reflection. I've used that in high-NA microscopy.
Cheers
Phil Hobbs
-- Dr Philip C D Hobbs Principal Consultant ElectroOptical Innovations LLC / Hobbs ElectroOptics Optics, Electro-optics, Photonics, Analog Electronics Briarcliff Manor NY 10510 http://electrooptical.net http://hobbs-eo.com
Only in German. In English we capitalize only proper nouns or those at the beginning of sentences.
Cheers
Phil Hobbs
-- Dr Philip C D Hobbs Principal Consultant ElectroOptical Innovations LLC / Hobbs ElectroOptics Optics, Electro-optics, Photonics, Analog Electronics Briarcliff Manor NY 10510 http://electrooptical.net http://hobbs-eo.com
Well I've got a pair of these,
George h.
Here's a 12-bit, 250 MHz ADC a couple inches from a multi-output switching power supply. The 6-diode CW multiplier string is about an inch away.
Noise is below 1 lsb RMS.
One solid layer 2 plane. Everything is grounded.
-- John Larkin Highland Technology, Inc lunatic fringe electronics
bolt
s that
I
Hah! I turn 61 in October. Respect your elders.*
George H.
*In grad school there was this smart Korean student. He'd been in the lab for years and I was the newcomer post doc, who barely knew anything of the field. (FIR spectroscopy of semiconductors) But I knew a bunch of electronics and low temperature techniques. He would dismiss all my suggestions, then he learn ed one day that I was a few weeks older than him. Like day and night I was no w his elder to be respected.. it struck me as weird, but totally part of Kore an culture according to the other Korean students at the school.
Sure, but star grounding has a place at low frequency. I cut my star grounding 'teeth' making a low freq. teaching lockin.
Where a uV of 'signal' getting into the wrong input would ruin my whole day.
George H.
re item, when mechanics is omitted
It's my experience with motherboards that electrolytic capacitors rank as the #1 cause of failure. In regards to connectors, it recently took me /weeks/ to debug hookup wire connectors on an audio mixer amplifier. The circuit itself took less than a day to design and a prototype was up and running by the end of the second day. Then, back in late June, an article about the feasibility of using
28 AWG IDC as audio hookup was posted by me. Your follow up inspired me to use hand twisted hookup wire instead. Easy peasy. All hell (hum actually) broke loose after everything was initially crammed into a 4" x 2.8" x 2" Bud box. It took a lot of time and effort to make the hookup connectors mechanically reliable. The project details will appear in the near future at my website. 73,-- Don Kuenz, KB7RPU
Exactly. The noise is in the details.
"The first rule is that there are no rules."
-- John Larkin Highland Technology, Inc lunatic fringe electronics
These have been very reliable:
The red IDC part is
TYCO 640440-3
10 cents.-- John Larkin Highland Technology, Inc lunatic fringe electronics
SED needs more cat pictures!
-- John Larkin Highland Technology, Inc lunatic fringe electronics
My recent audio mix-amp project motivated me to read, or at least skim, dozens of articles about /audio/ ground loops. Either Bill Whitlock or one of the other gurus said something along the lines of ground is a equal potential myth used by engineers to make their jobs easier. The exact wording and source of that aphorism are temporarily lost to me. It's Whitlock who definitely dispels other myths about trying to use thicker grounds or multiple grounds to fight loops.
Thank you, 73,
-- Don Kuenz KB7RPU There was a young lady named Bright Whose speed was far faster than light; She set out one day In a relative way And returned on the previous night.
No, we don't. Otherwise it will become FB!
John ;-#)#
My recent audio mix-amp project motivated me to read, or at least skim, dozens of articles about /audio/ ground loops. Either Bill Whitlock or one of the other gurus said something along the lines of ground is a equal potential myth used by engineers to make their jobs easier. The exact wording and source of that aphorism are temporarily lost to me. It's Whitlock who definitely dispels other myths about trying to use thicker grounds or multiple grounds to fight loops.
To avoid a potential misunderstanding, gurus generally advocate star grounds, as you did above.
Thank you, 73,
-- Don Kuenz KB7RPU There was a young lady named Bright Whose speed was far faster than light; She set out one day In a relative way And returned on the previous night.
AFT.pdf?dl=1
se at
Well, maybe:
Which opens with:
"Capitalization is the writing of a word with its first letter in uppercase and the remaining letters in lowercase. Experienced writers are stingy with capitals. It is best not to use them if there is any doub t."
However it depends on the usage... New York City vs the city of New York, and so on.
John ;-#)#
But we don't put die Capitals just so die dummkopfen Fremden can recognize die Nouns. ;)
Cheers
Phil Hobbs
when I took and emi class at uni one of the first thing the guy said was something along the line of "ground does not exist"
/ bolt
ers that
--I
,
b for years
d low
rned
now
rean
I believe too much respect for seniority between pilot and first officer has been noted as a possible contributing factor to statistically high numb er of plane crashes for Korean air in the 90's
ElectronDepot website is not affiliated with any of the manufacturers or service providers discussed here. All logos and trade names are the property of their respective owners.