Remember that power supply implementation info I sent you about a year back?
That item is so controlled regarding micro differentials, that if used between an amplifier and it's battery supply, the battery will go from lasting 6-8 hours, to over 3 days. This, with everything else being the same.
There is a huge difference between capacitor on the socket and capacitor on PCB. If capacitor is on PCB a peace of cable from socket to PCB will act as antenna inside of the box. Like, imagine you sit on an iceberg wearing warm puffy jacket, but put an iron rod through a sleeve, so it is half inside, half outside. Cool? 
Near perpetual motion, KBK? Keep up the good work, these people are not ready yet, but when it can be proven with a 'double blind measurement' they will be forced to believe. P.S, you should not mention new research here, it gets put where 'cold fusion' gets placed, and that is not good for either you or me.
Hi,
Guitar Amp's work like that even with the earth tied to the chassis because they are stand alone, as soon as they are no longer, they are earth loop central...
Ciao T
Guitar Amp's work like that even with the earth tied to the chassis because they are stand alone, as soon as they are no longer, they are earth loop central...
Ciao T
Exactly, they do not play well with others. There's a reason that so many effects pedals use batteries.
One minor bit to clean up about bypass capacitors in RF gear. Most Rf gear is concerned with keeping RFI in! The leads to the pass through are inside a case and often close to the chassis. This gives them a quite different behavior than a loose free standing cable outside the case.
In the example of putting a small cap across a TV feed, that will kill most of the spectrum. But there will still be some resonances that pass it. Murphy's law is clear that if you sell audio gear those frequencies that do get in will kill you!
When I do a cable TV system (I have built a few with roughly 1000 taps) I explain to the crew how loose crimps, kinks in the cable and other errors may not show up where they are but will often cause a TV some distance away to have trouble with a single channel or two. This is where there may be ingress of local stations or the increased reflections cause a cancellation. Virtually all of them get it as at home where they have cable they often have problems with a few channels.
In the example of putting a small cap across a TV feed, that will kill most of the spectrum. But there will still be some resonances that pass it. Murphy's law is clear that if you sell audio gear those frequencies that do get in will kill you!
When I do a cable TV system (I have built a few with roughly 1000 taps) I explain to the crew how loose crimps, kinks in the cable and other errors may not show up where they are but will often cause a TV some distance away to have trouble with a single channel or two. This is where there may be ingress of local stations or the increased reflections cause a cancellation. Virtually all of them get it as at home where they have cable they often have problems with a few channels.
That is, so-called linear distortion?
This sounds a little like the statement that all real capacitors have noise which I saw stated in a comment to a piece of Castor-Perry's the other day. I could think of two interpretations: one was noise in lossy dielectrics, which actually becomes important for lowest-noise charge amplifiers, with the traditional metal-case device borosilicate glass being rather poor. And similarly condenser microphone capsules have it, although it's difficult to separate that from the Brownian air molecule noise and the thermal-mechanical noise. The other is just the thermodynamic-equilibrium argument, where any capacitor has a mean-squared noise charge of kTC, the equilibration time being proportional to the parallel resistance.
Of course a lot of capacitors are a lot worse than others. When I had the chore of designing a "front-end" for a switchmode amp, I prefaced things with a JFET source-follower input with a current source load and a bootstrapped drain, and used d.c. coupling with a servo. The input d.c. termination was a megohm, which made the problems if any from the capacitors in sources with a.c. coupled outputs less significant.
However it permitted the not-too-well-versed people who initially tested the board in my absence to hook it up with clip leads
and get sustained oscillations from amplifier output-input feedback, which started to burn up one of the output networks That drove a change in which such oscillations or other excess high-frequency energy were detected and triggered protection. Oh well --- that was a crowded little 4-layer board towards the end. It sounded very nice driving some big Pioneer (or whatever that "high-end" offshoot brand is) speakers, and measured well, but I didn't have a lot of audition time so I'm not sure how much I would like it in the long run.Brad
Did you miss my picture of the DA noise in the mica cap? You are right dielectric loss in a mic capsule is usually a design oversight, I saw it in one brand but it dissappeared with a later rev of the diaphragm.
By the same arguments all non superconducting wire has resistive noise. No, I think Ed is saving up something special.
I did miss that I guess (the mica DA noise).
In the Reticon spectrometer preamps (one per video line) I used teflon tubing to separate the JFET gate lead from an alongside short piece of wire. The whole works were in a vacuum and tightly temperature-stabilized. The capacitances were about 170fF, which set the overall charge-to-voltage conversion gain of that stage. But the preamp's noise (~180 rms electronic charges per readout) was strongly dominated by the borosilicate glass in the 2N4416s and the MRF502s used as a pulsed reset transistor, the latter selected for <100fA Icex at 5V and room temperature. It was fun to look at the slow ramps on the outputs due to the net input current at operating temperature (around dry ice temps), respectively 1 and 3 fA. Although somewhat larger JFETs would have been a better noise match, the dielectric noise spoiled things already.
If there had been a budget for it, and if the project's protracted development hadn't made me enough enemies already, I could have gotten some alumina or BeO or BN -packaged chips, as did Kern and Mackenzie at Bell Labs.
Well, I will get my oscillation overthruster in readiness for the Simon revelations.
Brad
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