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In Reply to: Re: Wading into the waters (I'll probably regret it) posted by Dan Banquer on April 1, 2007 at 06:54:49:
Dan,Someone on the "other site" measured some conductance on the outer stuff, it's not clear to me whether it was an attribute of the ceramic or a coating upon it. Whichever it was, it's probably the key to this thing, if indeed it's anything beyond flummery.
My current philosophy is to assume that other's experiences are usually true and that their explanations for the same are usually bogus. If that's the case here, it behooves one to consider what might actually be happening within the device. If indeed the shell is resistive, then a reasonable model would be a series resistor and inductor, the WW resistor, shunted by a resistor, the shell. Due to the geometry of the thing, the shell, for lack of a better term, will have low inductance and should remain largely resistive into the GHz region. So throughout a large part of the spectrum it will be lossy. Unfortunately I haven't been able to tell from the postings how conductive the shell is. Based upon your measurements the corner of the resistor is about 15KHz so the effect, if any, will be above that.
If you have access to other gear, perhaps at work, try measuring the critter at much higher frequencies. The interesting point would be the location of the second corner where the outer conductance dominates the transfer function.
I think your position is that measurable electrical characteristics of the device, will fully account for any effect that it may have. I suggest that if you fully characterize the device electrically and then build another that exhibits the same characteristics then you are ready to put your theory to the test. If they both "sound" the same you will have proven either that the quantum BS is just that or that your device exhibits the same magic, which it may. If different, then there may be more things in heaven and earth...
For what it's worth, I tend to believe pragmatically that I don't need to worry about quanta below q. I've made my living for four decades using that assumption and have seen no reason to doubt it. But I'm keenly aware that engineering is based completely upon simplified models of the "real" world, and mine may be simpler than most. You just can't get anything accomplished without deliberately ignoring a lot of stuff and experience brings you up short when you've guessed wrong.
Good luck in your investigations. I would really like to know if there is anything to this. Certainly the "technical" marketing stuff on their website is highly off-putting, but the hell of it is that doesn't necessarily mean that it doesn't help in some fashion.
Follow Ups:
If it was an outer conductance it would bypass the resistor encased in the unit. This appears not to be the case as the LCR measurements show, and I took a frequency response to below 10 Hz. If it is supposedly a shield it would be connected at one end, and to ground. There is no ground connection only the two leads for the input and output.
Where do you want to go from here?
d.b.
Hi Dan,I want to go up in frequency! At some point the Xl of the resistor's inductance will be so high that the outer conductance dominates the impedance and you will see a "knee" where the impedance stops rising with increasing frequency.
If you can get gain access to an RF network analyzer you can be done in a matter of minutes.
Looking forward to what you find.
Actually if you take a close look at the LCR results the inductance is starting to go down at 100Khz. This is probably due to the capacitance between the "windings" of the resistor. Please: go back to the Audiocircle thread and take a close look at the LCR measurements.
d.b.
In order for this network to work at all at these frequencies for measurement the "resistor" would have to be a 50 ohm load over a huge band. Secondly, when does the AC line represent a 50 ohm load?
You might wish to take some time and think about the above.
d.b.
And I think that no one would spend the money on network analyzers that only analyzed networks that presented conjugate matches to the analyzer!The analyzer will be happy to tell you what's happening on networks that aren't 50 ohms. Just ground one end and look at S11 and you'll know what the impedance really is. If you have access to an analyzer buy lunch for one of the guys that use it a lot and I bet they'll be glad to help. If you don't, what do you have? There are a lot of ways to measure these things, and I've probably done most of them, but the network analyzers are cool and fast.
With respect to the inductance at 100kc, I'm looking at your data. Did you happen to notice what the Q was doing at the various frequencies? Also I'm not clear what the column with ohms as a unit is. Is it the impedance of the DUT or the resistive component of the impedance?
You're probably right about stray capacitance rearing it's ugly head, you'll likely find a self-resonant frequency, but the Q may be low depending upon the shunt resistance. Watch the phase.
You might consider doing a careful sweep by hand using your function generator and scope noting amplitude and phase as you go. If there is any question about the Zo of the Fn generator or it's ability to drive low Z loads consider using a build-out resistor to give you exactly a 100ohm source.
On behalf of myself and likely many other interested folks, thanks for looking into this.
Rick
O.K. Rick, Let's take a close look at some microwave theory here.
If you take that analyzer and connect a length of romex or line cord, and terminate into 50 ohms, your insertion loss and return loss will be all over the map. Why? because romex is not a 50 ohm line. The insertion loss alone will negate any conducted power along the line. Now instead of a nice clean 50 ohm termination use a variable termination of anywhere from 1 ohm to 10K ohms and think of the insertion and retrun loss under those conditions.
Now think of a power resistor claiming that it will absorb microwave energy and placing somewhere on the AC line. If you manage to place the resistor in exactly the right place it might reduce some RF, but in reality this will be purely by chance because we don't know exactly where the 1/4 wave will be. Move the "resistor" 1/4 of an inch and you will get a different response.
Now take that analyzer and connect something like a tripplite isobar, line cords and all with a varable termination. The isobar standard filters with real chokes, and MOV's will prove far losssier that the "power resistor". To it's benefit it will give some decent surge suppression, and low frequency RF attenuation where you really need it.
If microwave is an issue for household/consumer lines it will a radiated issue, not a conducted issue. Shielding will help, decent grounding practices will help, But if you think about any real power at microwave frequencies it should not be legal or allowed near any consumer or residence.
Now, for those of you who have their audio systems next to radar transmitters....................................
Hope this helps;
d.b.
Hi Dan,The reflected impedance is not quite ALL over the map. I presume the map in question is a Smith chart in which case it will be running around in a circle at the VSWR radius.
I don't think anyone claimed that the power resistor would absorb microwave energy, but I did speculate that it might provide a low impedance for the audio, or AC and that it's inductance would force higher frequency currents to flow more in the outer resistive layer which should stay resistive into the GHz region. As you pointed out, stray capacity in the resistor may limit it's ultimate attenuation.
As far as location goes, it probably doesn't matter as much as you'd suppose. To the traveling wave it's a loss, to the standing waves it varies, but except for the comb of frequencies where it's right at a current node it will help, especially since the reflected energy will pass through it over and over.
Microwaves are an issue for all of us nowadays, of course on the plus side it's convenient being able to hear our cell phones ring through the stereo... They may start radiated but usually end up getting picked up by the wires.
So, back to the issue at hand, I think we are looking for mechanisms that could account for the Bybee filters helping without invoking magic. Magic of course meaning things I don't understand...
I think we need to go back to the initial premise:
If it sounds like a duck, walks like a duck, and looks like a duck, is it a duck?
Not in High End Audio: it's the quantum visualization of a duck.
d.b.
OK Dan,Are you saying that girls WON'T be hopelessly attracted to guys with Bybee purifiers in their systems? You can trust advertising, we have laws...
It well may be floobydust and that further study would reveal nothing. Tis your call, you're doing all the work. I guess my electrons will just have to get along as best they can, smashing into each other and falling into holes like drunken sailors.
Regards, Rick
PS: I'm married to a birder. Just because something looks, sounds and walks like a duck no longer makes it a duck. Nowadays it's DNA has to declare it a duck. Thought you'd like to know...
Dan, it should be obvious from the photos that there are two metal endcaps that are soldered to each end of the resistor. Yes, there is conductance across the outside case, but its measurement is swamped out by the low value resistor in any 'normal', you know, RLC measurements. Hint: Think microwave.
John,I finally can't resist asking although I probably shouldn't, just what is your position with respect to these products? You appear very knowledgeable about them but seem unwilling to do more than drop scattered hints regarding their operation, efficacy or application. NDA? Trade secret? Orneriness?
The goofy thing is I really can't tell if there is anything here to actually be interested in. The anecdotal reports are confusing and inconsistent and the marketing hype seems silly. Or a masterpiece of obfuscation.
Do you actually use these components?
Thanks, Rick
.3 microhenries and a small amount of shunt capacitance to earth ground will work for that. However since your outer shell is not connnected to ground I see little RF rejection here. Maybe you had some measurement issues here, microwave demands much care for accurate measurement.
d.b.
the large ones at least, are rated for basically unlimited voltage (at least 1000 volts and is more dependent on the insulation appplied) and 15 amps current. Tell me that that resister used is rated for 15 amps. That ought to give you a clue of what the ceramic tube is doing.
As for the black coating on the ceramic tube, ever notice that an ohm meter leads simply pressed against the surface reads open, but if you scratch the surface of the coating, it produces continuity?
How much continuity? Say from the center of the ceramic tube to an end? Even a rough measurement would be interesting.I would think that the resistor would be happy with 15A. If it's 25mohms that would only be 3/8 W.
Rick
The conductive ceramic body is NOT a shield. The resistor is inside, but it can be placed outside as well.
You sir, are on a phishing expedition. In a post below this you contend that 1/f noise is the issue. 1/f noise mathematically is only significant below roughly 10 Hz. This end of the thread you are talking the outer extreme of microwave frequencies. (1Ghz and up?)
Nice try but the bait isn't working, and I have better things to do than have this kind of nonsense served up in my face.
Get real;
d.b.
Dan, 1/f noise can start at 1 megahertz. Look at RF fets. What is wrong with you?
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