I think I'll skip your idea of a good time!
I did post a diatribe @ http://www.diyaudio.com/forums/lounge/194219-more-magic-stones-hockey-pucks-12.html#post2906241
Did I miss something? I have 50 years worth of acoustic measuring stuff here and no sign of a change in reference level. It is dB re 1V/Pa (or 1V/uBar) on all the cal charts I have seen. Or are you referring to the original Rayleigh disc measurements (which would have predated standards and were used to derive a level of hearing sensitivity)?
Actually late 1800's to very early 1900's. When reading Sabine the 10 db shift often comes into play!
No. I realise the older I get I know less and less can get into more trouble faster and faster. Happy belated birthday John.
I guess I was not paying attention that month
Too busy with the telegraph.The volt has changed as well as the second a little since the 1900's. Not enough to affect anything we care about.
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I guess I was not paying attention that month
The volt has changed as well as the second a little since the 1900's. Not enough to affect anything we care about.
Telegraph? Did Sam Morse get that contraption to work?
I guess the observation is similar to the thing I said in the last iteration of the thread, whihc is the only way to have no 1/f noise is to be using a perfectly realized superconductor.
Until then, depending on the linearity (dynamic vs switching speed limits vs hysteresis gives good hints) of the given junction design, there will always be varying levels of 1/f noise. Part and parcel of the the entire idea and reality of the atomic 'wave-particle' 'co-junctive' conditionals of a 'semi-conductor'.
If the hash noise of the 1/f function itself was cured, then the function of the given semi-conductor begins to more stair step than to 'curve gradually'. The noise is part and parcel of achieving a smooth curve. the other half is the choice of materials (element combinations), or semi-conductive materials, their purity and their method of being applied.
As Maxwell originally wrote in his original and full unedited equations, there is a unidirectionality, aysmmetricality and elasticity to electromagnetic function.
So much for Lorentz and Heaviside. (and every wrong step that needs futzing math to make it mathematically viable-that came afterward)
If the original equations where not the correct ones to be using in any form of analysis... the idea of a semiconductor would not work, whatsoever.
Let me say that in Buckingham, p.130, is a graph of noise at spot frequencies, 10,100,100K at different temperatures in a device, that completely obsoletes my original concept of 1/f noise. For example, how can you have 10Hz DROP, and 100Hz RISE compared to another temperature, and this graph is NOT smooth, not smooth at all.
Now, what if, for example 10Hz was all important, and 100 Hz was not? Then an operating temperature of 200K would would be optimum.
However IF 100 Hz was necessarily optimum, then about 240K would be best.
And near room temperature: 260K or so.
10Hz is awful, and 100Hz is not too bad, kind of typical of a noisy jfet
BUT at 300K, 100 Hz is awful and 10 Hz is almost as good as 100Hz which is at a 10dB lower value than 260K.
WHERE IS THE SMOOTH CURVE?
This is where reality defies engineering approximation.
This curve initially states that IF you want lowest 10 Hz noise, then you have to cool the working temp to 200K. And if you cool it further, the 10 Hz noise will rise abruptly, as will the 100Hz noise somewhat, and even 100KHz will be worse below 200K, UNTIL you approach 100K, THEN the 10Hz noise is about the same as the 200K value.
It is like the excess noise on whatever device they used is composed of a series of wobbles, perhaps quantum related, and no smooth curve.
Buckingham states that this was an Nch jfet, selected for low noise at room temperature. Go figure!
Buckingham's source for this graph was: Haslett and Kendall (1972) 'Temperature dependence of low-frequency excess noise in junction gate FET's' 'IEEE Trans. Elect. Dev.', ED-19 , 943-950.
I hope to find the original reference in time.
Now, what if, for example 10Hz was all important, and 100 Hz was not? Then an operating temperature of 200K would would be optimum.
However IF 100 Hz was necessarily optimum, then about 240K would be best.
And near room temperature: 260K or so.
10Hz is awful, and 100Hz is not too bad, kind of typical of a noisy jfet
BUT at 300K, 100 Hz is awful and 10 Hz is almost as good as 100Hz which is at a 10dB lower value than 260K.
WHERE IS THE SMOOTH CURVE?
This is where reality defies engineering approximation.
This curve initially states that IF you want lowest 10 Hz noise, then you have to cool the working temp to 200K. And if you cool it further, the 10 Hz noise will rise abruptly, as will the 100Hz noise somewhat, and even 100KHz will be worse below 200K, UNTIL you approach 100K, THEN the 10Hz noise is about the same as the 200K value.
It is like the excess noise on whatever device they used is composed of a series of wobbles, perhaps quantum related, and no smooth curve.
Buckingham states that this was an Nch jfet, selected for low noise at room temperature. Go figure!
Buckingham's source for this graph was: Haslett and Kendall (1972) 'Temperature dependence of low-frequency excess noise in junction gate FET's' 'IEEE Trans. Elect. Dev.', ED-19 , 943-950.
I hope to find the original reference in time.
Volumetric changes and conductivity changes in atomic structure as a parallel path and overlay upon one another... are probably among the greatest clues. At least as an idea of external observation.
A line is preferred over that of a curve. Which is gotta be the most obvious 'duh!' statement for an audio related thread. the origins of any curve aspect are key. More duh. In the final analysis, with nothing that is current (in time and knowledge base of public science) being changed...Graphene may make a better gate than a D-S in any transistor attempt.
I lost my original post. Which is probably a good thing.
Regarding temperature, in my understanding...you are getting quanta to quanta velocity or voltage differential/electron flow propogational rate and distribution/polarity related differences due to wave-particle distance/polarity changes. One could get into the mirror aspect of the aether function which is a source of part of the random (brownian) noise function but that gets ugly pretty fast, regarding being outside of the discussion.
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