Ah you at least looked at it! Now where did you get the #12 wire from? 22 gauge wire has a cross sectional area of .33 mmsqd. But this gets back to the long tale.
scott
I wanted to avoid spikes passing through a powersupply to sensitive circuit, as a protection measure and possibly lower amplitude of spikes.
kim
I wanted to avoid spikes passing through a powersupply to sensitive circuit, as a protection measure and possibly lower amplitude of spikes.
kim
You might want to check out transient voltage suppressors Transient Voltage Suppressors - TVS
They come in a range of low voltages.
The issue is to see if there actually is an explanation for some of the observed results which get dismissed out of hand because they conflict with what some learned either before the research or at a level of theory that may work well for almost everything but not for the observation (or perceived observation) under question.
Burble Bees or some such attract vast derision. Would graphene if it were marketed to the same crowd?
Now one of my favorite dismissed out of hand gizmos are those that spray a bit of RF into the listening room. Now this may not be the design intent of the device or the explanation given as to what it does, but I did a measurement that indicated certain RF frequencies even at low level may have interacted with the moisture in the air to decrease high frequency attenuation. I got 1/2 of a dB difference in the 16,000 hertz band. This is well into the area of uncertainty. If I was really motivated I might try more specific experiments. But it at least hints that these devices might actually do something. However as a 1/2 dB boost at 16,000 hertz can be achieved by much easier methods, why bother?
My basic feel is when a group of folks observe something interesting it may be worth a look, you never know what you might find. Calling them idiots isn't really productive and certainly does not expand ones knowledge.
Have you ever stumbled upon something that seemed wrong to others but actually happens?
NO! This is great stuff, and I hope it conveys the true nature of the physics of electron flow, rather than the common assumptions and generalizations.
Everyone should at least attempt to read the 50 page paper, most of you won't get far, but then you will know the extent of everyone's ignorance on the subject.
Everyone should at least attempt to read the 50 page paper, most of you won't get far, but then you will know the extent of everyone's ignorance on the subject.
Because somebody is claiming Ohm's law is no longer good enough for audio electronics. In my book, this is at par with Bybee devices cleaning up signal from noise.
But you are right, debating Ohm's law and Bybee devices is useless, there is a funny side, though. To watch some otherwise respectable people sweating over the impossible has it's entertaining value. In particular when you know they must know better.
No Marce here.
You would Not want to use the GDT technology in a DC supply for audio. Once they conduct due to over-voltage, they do not stop conducting until the DC voltage drops well below the 'firing' threshold...... such as would happen when the fuse blew.
For a fast Tr nd short duration pulse or spike of high voltage, an MOV or similar is useful. They wont affect filtering or increase Z on the PS line. They represent a short for the period of over voltage duration and then go back to a high Z state.
THx-RNMarsh
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For low level spikes, a linear filter is probably more useful (LC for example).
In practice, both are almost always associated: the linear part eliminates frequencies outside of the range of interest, and provides a series impedance to allow the non-linear part (TVS, transil, gas arrestor) to operate in an effective and non-destructive way.
You probably would like to read the documentation from Epcos, ST and the like on the subject: they provide good general information
tl;dr.
It's how you tell them.
Your elaboration of conduction is more entertaining, but that's not saying a lot. You're just restating what Scott said, but trying to contrive to make it sound different. So what?
Read post #68400
No I think we agree on what is happening it is the results of this where we differ. (BTY if you go back to where it started I think you will find Scott has changed.)
Here's one for you.
I just opened a new pack of cocktail sticks. They're all only sharpened at one end.
I just opened a new pack of cocktail sticks. They're all only sharpened at one end.
Simon7000,
Of course in my many years of development I have seen things that I was told would or could never happen. I have also done things I was told would never work, not possible that I have made work and did not divulge how I did it.
On your example of RF affecting the high frequency absorption or attenuation I could throw out a just as plausible explanation that it had nothing to do with the RF generation and everything to do with the change in air density caused by humidity. I have no proof of that but it makes more logical sense than that an RF signal would affect anything at such a different frequency. Are you proposing that the RF was modulating the air due to humidity, that seems to be what I get from your explanation? I would think it would take a very high level RF signal to do anything to water molecules in air, let alone to modulate an audio signal in air. We surely aren't talking about microwave absorption or you would have been inside a room like a microwave oven, not a very safe place to be!
But who knows what other factors were being affected by that RF? Injection into the audio stream through a component would be more likely I would think.
Of course in my many years of development I have seen things that I was told would or could never happen. I have also done things I was told would never work, not possible that I have made work and did not divulge how I did it.
On your example of RF affecting the high frequency absorption or attenuation I could throw out a just as plausible explanation that it had nothing to do with the RF generation and everything to do with the change in air density caused by humidity. I have no proof of that but it makes more logical sense than that an RF signal would affect anything at such a different frequency. Are you proposing that the RF was modulating the air due to humidity, that seems to be what I get from your explanation? I would think it would take a very high level RF signal to do anything to water molecules in air, let alone to modulate an audio signal in air. We surely aren't talking about microwave absorption or you would have been inside a room like a microwave oven, not a very safe place to be!
But who knows what other factors were being affected by that RF? Injection into the audio stream through a component would be more likely I would think.
Sure. Even with a humble 2N3904 operated at a peculiar combination of biases and at very low currents. I recall being flat-out disbelieved by a boss who thought he knew about all there was that needed to be known about the part. And for conventional use he was probably right, although he had a habit of oversimplification (the collector impedance was so high as to be disregarded, things like that).
I have little doubt that the behavior could be explained by standard semiconductor physics though.
Another time I was testing 1Tohm chip resistors at liquid nitrogen temperatures and saw a distinct pattern of random step changes in conductance. Needless to say that part was rejected for a InSb photodiode preamp.
And then there was the tech who was shocked twice in a row by a strobe light power supply, and thereafter was a powerful source of interference. You could hear whatever it was demodulated by a powered loudspeaker, and I was certain he was pulling my leg, and that he'd reveal a noisemaker concealed in a pocket or something similar. Nope. Eventually it died down. Another one for the Journal of Irreproducible Results. Journal of Irreproducible Results - Wikipedia, the free encyclopedia
Kindy, That well could be the reason.
Brad, I didn't intend to set anyone up on the short novel, but feel free to retell the funny parts.
And just how did people see before eyeglasses?
To me the humor of course is that acoustics plays a much bigger role in sound reproduction than almost all of what is discussed here. Last time I mentioned the unit of measurement the sabin, it drew a complete blank on understanding.
Noise levels just got the treatment, so we probably should not even get into reflection patterns.
But it is often fun to play with bits and pieces. My resistor bit really has legs.
I really need to finish my power supply work. I was trying to review it here but it seems to have drawn a blank except for a few.
I still think the attached is quite an eye opener. But only George responded.
Brad, I didn't intend to set anyone up on the short novel, but feel free to retell the funny parts.
And just how did people see before eyeglasses?
To me the humor of course is that acoustics plays a much bigger role in sound reproduction than almost all of what is discussed here. Last time I mentioned the unit of measurement the sabin, it drew a complete blank on understanding.
Noise levels just got the treatment, so we probably should not even get into reflection patterns.
But it is often fun to play with bits and pieces. My resistor bit really has legs.
I really need to finish my power supply work. I was trying to review it here but it seems to have drawn a blank except for a few.
I still think the attached is quite an eye opener. But only George responded.
Attachments
In another thread I just read a post, followed by additional approving ones, that it was 1/f noise in MOS output devices that accounted for issues with the audible performance.
But we can read, in Linear Audio (from whom I receive no promotional consideration btw despite referencing it frequently) Burwen's belief that a small change in the room (I mean tiny stuff) will have an audible effect.
I almost commented on the power supply post, mainly about nearfield/farfield behavior, but I was saved the trouble by George and others.
All of this can be stimulating. I have learned more about short-channel MOS behavior, especially noise, in the last two days than in the previous several years. Nothing particularly applicable to audio circuitry (other than digital hardware) but fascinating nonetheless. Who knew that P channel could be a lot quieter than N in the submicron regime? A shocker.
But we can read, in Linear Audio (from whom I receive no promotional consideration btw despite referencing it frequently) Burwen's belief that a small change in the room (I mean tiny stuff) will have an audible effect.
I almost commented on the power supply post, mainly about nearfield/farfield behavior, but I was saved the trouble by George and others.
All of this can be stimulating. I have learned more about short-channel MOS behavior, especially noise, in the last two days than in the previous several years. Nothing particularly applicable to audio circuitry (other than digital hardware) but fascinating nonetheless. Who knew that P channel could be a lot quieter than N in the submicron regime? A shocker.
Elvee
Thanks Elvee. This particular PS use LC. Was trying to minimize garbage to first choke as usual. I thougt that maybe there was an arrestor type suitable. Obviously effectively and non-destructive. The arrestor is basically shunting to ground at a certain voltage. But otherwise invisible ? Thanks for new reading.
Kim
Thanks Elvee. This particular PS use LC. Was trying to minimize garbage to first choke as usual. I thougt that maybe there was an arrestor type suitable. Obviously effectively and non-destructive. The arrestor is basically shunting to ground at a certain voltage. But otherwise invisible ? Thanks for new reading.
Kim
Exactly - and this is one reason why it's worthwhile to understand device operating principles in depth. 'Humble' is just a humanisation after all. Components are what they are, and only by exploring the causes of how they behave might one predict aspects beyond the scant and mundane application datasheet parameters, IMO.
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