R67 actually is not needed in this application because there is a load on the output. I usually use 100K in this type of application to be sure the capacitor has a place for the DC offset to go to ground.
Wowie! you found a typo yes the values in the table for R62 and R63 are swapped.
Thanks
Auplater, have you ever read Ragnar Holm's book 'Electric contacts'? If you have not, we have nothing to discuss at this time.
Thanks for this info, John L. The lack of real data on this subject is also something I've noticed, so that's why I'm interested in Ed's article and any other info I can find.
Surprise! If you read what I wrote you would see that is one of the results of the measurements! Plated contacts really behave much like the base metal.
There is a type of plating that I every so often see on the cheap imported connectors that starts out bright and shiny silver and after a while gets a white film. At that point most of the connectors just stop conducting low level signals. Cleaning them so that they work is a very short fix, the oxide comes back. That is what I called bright and shiny it is always interesting to see how others read things and even more interesting to see how those who did not react.
By the way what is the conductivity of electroplated copper? It measures different than annealed copper.
auplater,
Good Lord John! You got off of your rant stand and provided really sensational information! Thank you!
Bud
Good Lord John! You got off of your rant stand and provided really sensational information! Thank you!
Bud
ummm
Actually, I did read the whole post... you seem to misunderstand the ramifications of copper diffusion through thin gold plating... it corrodes and leaves a non-conductive film or worse... bad practice. Behaving like the base metal has nothing to do wrt passing signal, other than loss of contact, which seems pretty obvious to me.
the cheap=o connectors have either zinc plating or they have a flash coating of tin or solder. Not good, never have used them.
Who uses electroplated copper on interconnects? maybe a flash layer if made from steel, but who wants steel terminations. Electroplated copper can be very highly conductive, again it depends on the conditions under which it is produced. Hey, you don't have to believe anything I say, just passing on decades of experience, experimentation, and succesful commercial electrochemistry.
Cheers
John L.
Actually, I did read the whole post... you seem to misunderstand the ramifications of copper diffusion through thin gold plating... it corrodes and leaves a non-conductive film or worse... bad practice. Behaving like the base metal has nothing to do wrt passing signal, other than loss of contact, which seems pretty obvious to me.
the cheap=o connectors have either zinc plating or they have a flash coating of tin or solder. Not good, never have used them.
Who uses electroplated copper on interconnects? maybe a flash layer if made from steel, but who wants steel terminations. Electroplated copper can be very highly conductive, again it depends on the conditions under which it is produced. Hey, you don't have to believe anything I say, just passing on decades of experience, experimentation, and succesful commercial electrochemistry.
Cheers
John L.
no problemo
glad to be of help... I've posted this before a few years back.. but what goes around, comes around, I guess...😛
BTW: I was reading more about meta-materials and how they are used for "cloaking" of objects to make them invisible... Klingon-ish... maybe the EnaBL methodology could be related to cloaking of the bad behavior aspects of the micro-dynamics in the signal, somehow making the main information carrier transparent to their effects? Maaybe rename the process to SoniCloak😉
l8tr
John L.
glad to be of help... I've posted this before a few years back.. but what goes around, comes around, I guess...😛
BTW: I was reading more about meta-materials and how they are used for "cloaking" of objects to make them invisible... Klingon-ish... maybe the EnaBL methodology could be related to cloaking of the bad behavior aspects of the micro-dynamics in the signal, somehow making the main information carrier transparent to their effects? Maaybe rename the process to SoniCloak😉
l8tr
John L.
No cable can improve the signal sent through it. 5c pennypinching on the connectors can do helluva job spoiling it.
Holm said that there was a thin oxide layer on gold, but it would be so thin that electrons could tunnel through it.
Actually it looks as if we are not in disagreement. I assume you understand the measurement is of intermodulation distortion. The highest readings come from what you call "non-conducting films". (I suspect that is the same as what I consider barriers, punch through requires higher voltage, resulting in a dead zone thus more IM.)
I have written a bit here and elsewhere. The article is on how to make the measurements. Understanding what the measurements mean is open to interpretation.
As to the micro-diode theory. I measured a strip of copper, heated it until it had a nice oxide coating and measured it again. Same readings.
Most noticeable was the effect of commercial de-oxidizing compounds on connectors, they actually do seem to work.
seems to be common knowledge nowadays... it's 40 years l8tr after Holmes
INRS-Énergie, Matériaux et Télécommunications, 1650 Boulevard Lionel-Boulet, C.P. 1020, Varennes, Quebec, Canada J3X 1S2
Received 6 October 2003; Revised 11 March 2004; accepted 3 June 2004. Available online 28 August 2004.
Abstract
Gold thin films were deposited by pulsed laser deposition in presence of an O2
One of many abstracts googled
gold oxide
ScienceDirect - Thin Solid Films : Gold oxide thin film grown by pulsed laser deposition in an O2 atmosphere
"atmosphere. The background gas pressure varied from 6.7 to 119.7 Pa and the target-to-substrate distance was kept constant at 30 mm. Structural analysis of the deposited films was conducted by means of X-ray diffraction and X-ray photoelectron spectroscopy. Both X-ray diffraction and X-ray photoelectron spectroscopy analysis show that gold oxide is formed during reactive pulsed laser deposition of gold. The gold oxide content of the film increases up to about 85% as the O2 pressure reaches 53.2 Pa and remains constant for higher pressure. The stoichiometry of the gold oxide phase [O]/[Au] is 1.25, close to that expected for Au2O3, and does not vary with the O2 pressure. Gold oxide decomposes slowly with time upon exposure to the ambient atmosphere"
Author Keywords: PLD; X-ray diffraction; Nanomaterial; Nanostructure; X-ray photoelectron spectroscopy; Au2O3
note the last line...i could go on, but to what end?
Cheers
John L.
INRS-Énergie, Matériaux et Télécommunications, 1650 Boulevard Lionel-Boulet, C.P. 1020, Varennes, Quebec, Canada J3X 1S2
Received 6 October 2003; Revised 11 March 2004; accepted 3 June 2004. Available online 28 August 2004.
Abstract
Gold thin films were deposited by pulsed laser deposition in presence of an O2
One of many abstracts googled
gold oxide
ScienceDirect - Thin Solid Films : Gold oxide thin film grown by pulsed laser deposition in an O2 atmosphere
"atmosphere. The background gas pressure varied from 6.7 to 119.7 Pa and the target-to-substrate distance was kept constant at 30 mm. Structural analysis of the deposited films was conducted by means of X-ray diffraction and X-ray photoelectron spectroscopy. Both X-ray diffraction and X-ray photoelectron spectroscopy analysis show that gold oxide is formed during reactive pulsed laser deposition of gold. The gold oxide content of the film increases up to about 85% as the O2 pressure reaches 53.2 Pa and remains constant for higher pressure. The stoichiometry of the gold oxide phase [O]/[Au] is 1.25, close to that expected for Au2O3, and does not vary with the O2 pressure. Gold oxide decomposes slowly with time upon exposure to the ambient atmosphere"
Author Keywords: PLD; X-ray diffraction; Nanomaterial; Nanostructure; X-ray photoelectron spectroscopy; Au2O3
note the last line...i could go on, but to what end?
Cheers
John L.
Last edited:
Or perhaps something more up to date.
Electrical Contacts: Principles and Applications
It's a Google Books preview, but it's a very generous one.
se
Hey AU - I thought that most connectors where plated with something between the copper and the gold. Is that not the case? Is the gold right on the copper on most audio connectors?
I don't know much about metal plating, so please forgive the question.
I don't know much about metal plating, so please forgive the question.
No, but some of them are capable of measuring parts per quadrillion signals. I personally have amps that are used for photon counting. Yes, individual photons (it sounds more impressive than it actually is). Also, my photomultiplier amps are considered pretty "slow" within my department, and are capable of measuring low nanosecond transients. My Berkley Nucleonics pulse generator (I just replaced my model 555 with a 575 if you are really interested) is capable of 250 picosecond timing resolution and uses a $2 power cable. I'm quite sure that an audio amp can't do any of these things.
Point well taken! Here is a counterpoint:
I work in a university setting where there is a TON of custom equipment being designed and built. The PPQ instruments we have in the department were custom built in-house, from the machining of custom mechanical parts to design and construction of the custom electronic components. My PMT amps are custom built in house, from the circuit layout to the board design to the cheap aluminum chassis that was hand punched. We don't work under any ISO or IEEE standards, and none of us worry about interoperability, just good signals. Also, we never worry about power cables! We DO often put good filters on the input sockets, and there are tons of Faraday cages around the department, but nobody has any power cables costing more than a few bucks.
Just saying. . .
Looks like I need to read that article. Thanks very much for the information, and though I still doubt your conclusions, I must retract my questions regarding your methodology (at least temporarily 🙂 ). You seem to have taken many precautions to ensure that your findings would hold up to some scrutiny, and whether I ultimately agree with your conclusions or not, your attention to detail is much appreciated. Until I get a copy of the article to read, I will reserve further judgement regarding your data, methodology or results.
Well, absent any other disagreements, I completely agree with you there! If there is an oxidized coating on contacts, then signal transfer does indeed suffer appreciably. My experience with cables is that once I have gotten past a "decent quality" threshold, I haven't subjectively noticed any differences between cables. As a disclaimer, I have never auditioned some of the super high-end esoteric cables, so I don't have nearly as much room to talk about the range of possibilities as others.
What I can say is that all of the decent coaxial cables that I have used for audio signal transfer, from some of the goofiest quad shielded coax that we have on the shelf in my lab (I used scraps that I pulled from the trash, so please spare any "stealing from work is bad" comments) to mid grade guitar cable, haven't made any difference that I could tell. Similarly, whether I use RCA, BNC, SMA or gold plated pin connectors, I can't tell the difference. I DO tell a difference if I use old, cheap, corroded cables.
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