Do you do any coding Bill? 'cos audio filtering in DSPs isn't hard; modern devices have plenty of grunt so efficient code isn't important. And it's fun....
> arcing has absolutely nothing to do with the behavior of bad or
> dirty contacts that make or break with mechanical agitation.
I'm not talking mechanical ' agitation ' ............
I mean the variance of the signal voltage
It manifests like a super class B 'ness .....
> dirty contacts that make or break with mechanical agitation.
I'm not talking mechanical ' agitation ' ............
I mean the variance of the signal voltage
It manifests like a super class B 'ness .....
Do you do any coding Bill? 'cos audio filtering in DSPs isn't hard; modern devices have plenty of grunt so efficient code isn't important. And it's fun....
It's on the list. I've never been good at code despite trying since I got my first 8 bit machine. Probably time to learn.
It can't do L-R to M-S conversion and I need twiddly knobs for adjusting. The pragmatic approach would be to do the conversion in analog and feed through a DEQ2496 , but that's extra conversion stages and the UI on the DEQ isn't great. I fear once again I am in a group of one in my requirements.
Yup, that is the cheapy version!
I've got an old Rane graphic if you want it
I'm not talking mechanical ' agitation ' ............
I mean the variance of the signal voltage
It manifests like a super class B 'ness .....
I understand but it can't there is no physics for that. Did you read the quote, a several micron gap is an open circuit to several hundred volts metals touching is ohmic? The minimum voltage in air to jump a gap at atmospheric pressure is 327V. The only variance would come from ohmic changes due to current density. At small signals there is not much possible going on and it would be symmetric not rectifying I would think in any case. I certainly am open to any evidence otherwise.
I could suggest some experiments like take two very fine wires contacting at 90 degrees passing a very small signal sin wave and them slowly break the connection and inspect the result as the connection is broken.
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There is some info I could not find in a quick scan of the net on low level signals and contacts. JC probably has hard copy somewhere. In any case on initial contact, some energy level is needed to initiate conduction. Once that has happened its a continuous metallic connection (no class B dead zone). The energy level needed is very low. I have meters with sub microvolt sensitivity at 100 MegOhm Z with input relays that work fine. I do not think it's an issue. The relay I linked to is a reed relay in a system with -140 dB internal harmonics. A distorting relay would really stand out in that application.
There is some info I could not find in a quick scan of the net on low level signals and contacts. JC probably has hard copy somewhere. In any case on initial contact, some energy level is needed to initiate conduction. Once that has happened its a continuous metallic connection (no class B dead zone). The energy level needed is very low. I have meters with sub microvolt sensitivity at 100 MegOhm Z with input relays that work fine. I do not think it's an issue. The relay I linked to is a reed relay in a system with -140 dB internal harmonics. A distorting relay would really stand out in that application.
Reed relays are sealed. The issue for unsealed relays is what the atmosphere does to the contacts. I haven't seen a glass sealed conventional relay. Plastic cased relays are subject to out-gassing. That is why bifurcated crossbar contacts are used. High mating force and four contact points. One of the four should mechanically punch through the contamination. A practical solution.
Reed relay distortion drops as current decreases, so high impedance circuitry would reduce distortion and mercury wetted contacts would allow low level operation. The right relay properly used.
My last physics prof friend was very succinct on the subject. The rules apply 80%+ of the time, but not always. (Who would have though there is a difference between theory and reality?) He also had a rig where the low level problem showed up.
His other interesting story was one of his major projects required no iron in the vicinity. They had to pull the rebar out of the concrete in his space, not a cheap project.
His other interesting story was one of his major projects required no iron in the vicinity. They had to pull the rebar out of the concrete in his space, not a cheap project.
That's why I had to build a wooden bench for my air core coils. Steel top benches were standard issue.
EDIT - Sorry I missed the point, we never used unsealed relays for anything and I have only used one as a turn on delay for power supplies.
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> I certainly am open to any evidence otherwise.
I'm surprised you've never had it happen ....
I'm surprised you've never had it happen ....
> I certainly am open to any evidence otherwise.
I'm surprised you've never had it happen ....
Not what you describe, abrupt rectification as in a singularity of derivative in V/I. Why not make a little picture of what you mean if that is not it. Cat's whiskers, etc. are semiconductor junctions and behave more or less like a diode.
Example copper to grossly corroded copper, no "dead zone" Home Made Diodes From Copper Oxide | Hackaday
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Yes. O.K.....
Perhaps "arc" is a wrong way to look at it.
Too ' glowing ' of a description 🙂
Watch out these guys go all the way. Electrical Experimentalists: Our Community Grows | Space News – The Thunderbolts Project ™
Democratization of science. Watch out for the guys toying in their sheds with CRISPR.
We live in an age of militant science and philosophical materialism. Not going to respond beyond that.
Democratization of science.
Well said, the electric universe also comes with the typical disdain for all theory and math.
The idea that outsiders ("the people") will revolutionize physics, in a way that those outsiders understand, is powerful. "Science is returned to the people—the garage tinkerer, the practical engineer, and the natural philosopher," Thornhill told Motherboard. "People say to me that it has changed their lives because it makes sense for them," he said. "And because it is a real cosmology, there is something for everyone, be they scholar, artist, engineer, or the 'man on the street.'"
We live in an age of militant science and philosophical materialism. Not going to respond beyond that.
Says the guy using a computer (or even better, a smart phone) on the internet.
xkcd: Science
"Science. It works bitches!"
Dawkins: YouTube
Cheers,
Jeff
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Says the guy using a computer (or even better, a smart phone) on the internet.
"Science. It works bitches!"
What a strange thing to say. Like I said, more militant science. Science works alright, just don't make it into a war. I don't intend to engage in it. Make peace, OK?
Joe those Electric Universe guys are in Melbourne, have you come across them? The comments on their videos are from anti-science posters as scary as any militia out to do harm as I have seen. Peace is not on the agenda.
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Joe those Electric Universe guys are in Melbourne, have you come across them?
No. Why?
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