Path: ...!Xl.tags.giganews.com!local-1.nntp.ord.giganews.com!nntp.supernews.com!news.supernews.com.POSTED!not-for-mail NNTP-Posting-Date: Mon, 24 Jun 2024 14:52:36 +0000 From: john larkin Newsgroups: sci.electronics.design Subject: Re: Interesting reading about spread-spectrum, also for on-board designs Date: Mon, 24 Jun 2024 07:52:36 -0700 Message-ID: References: <45mo6jhcq8kisjmbrom8i1r17ljr6g4qu8@4ax.com> <6rrt6jdnu9q86jc81n3pt3jqli1t42te8f@4ax.com> User-Agent: ForteAgent/8.00.32.1272 MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Transfer-Encoding: 7bit Lines: 82 X-Trace: sv3-jIke6hewh7M5ID2Jkjl+1ChEWcwH8WxK4RpSLhPz9QMQAKJ+yIeNwaBDFOjEK9N7qSjUktHH6AnEOFq!d0xTG4rLUZUJRdi6tIbDaDN0ruUBUDKzSlkXIBScfHZZFpUXQCcCnRPBaF9ug0dv3MVvp7opX/Q1!4Bj8nA== X-Complaints-To: www.supernews.com/docs/abuse.html X-DMCA-Complaints-To: www.supernews.com/docs/dmca.html X-Abuse-and-DMCA-Info: Please be sure to forward a copy of ALL headers X-Abuse-and-DMCA-Info: Otherwise we will be unable to process your complaint properly X-Postfilter: 1.3.40 Bytes: 4434 On Mon, 24 Jun 2024 10:35:42 -0400, Joe Gwinn wrote: >On Sun, 16 Jun 2024 07:01:41 -0700, john larkin wrote: > >>On Sun, 16 Jun 2024 05:26:35 GMT, Jan Panteltje >>wrote: >> >>>On a sunny day (Sat, 15 Jun 2024 08:43:12 -0700) it happened john larkin >>> wrote in : >>> >>>>On Sat, 15 Jun 2024 05:57:23 GMT, Jan Panteltje >>>>wrote: >>>> >>>>>On a sunny day (Fri, 14 Jun 2024 07:55:14 -0700) it happened john larkin >>>>> wrote in <45mo6jhcq8kisjmbrom8i1r17ljr6g4qu8@4ax.com>: >>>>> >>>>>>On Fri, 14 Jun 2024 07:43:53 GMT, Jan Panteltje >>>>>>wrote: >>>>>> >>>>>>>Interesting reading about spread-spectrum, also for on-board designs: >>>>>>> >>>>>>> >>>>>>> https://www.electronicdesign.com/technologies/power/article/55041243/monolithic-power-systems-choosing-the-proper-parameters-in-frequency-spread-spectrum-fss-design >>>>>> >>>>>>That's cool, except for the usual dreadful fake pcb image. >>>>> >>>>>Fake? >>>>>Sure some fun zig-zag loops in some tracks... ? >>>>>Why would anybody bother making artwork like that when you can just take a picture? >>>> >>>>I've wondered that. And when they use a picture, it tends to be some >>>>ancient crufty Dip-package board. >>>> >>>>I have rarely used wiggle traces to add delay, but the fake board >>>>images are full of them. And glowing traces. And vias without holes. >>>> >>>>Hey, the electronic designers here could post pics of our prettiest >>>>real circuit boards. >>>> >>>>> >>>>> >>>>>>We have a bunch of switchers that use our own FPGAs as the >>>>>>controllers, and I need to start up a project to make them >>>>>>spread-spectrum. >>>>> >>>>>I find it interesting, not much experience with spread spectrum, >>>>>but a lot with wideband FM modulation like for the old Ampex video recorders... VHS, Umatic, Betamax too. >>>>>So with a bit of luck you can send your commercials on a few hundred kHz :-) >>>>> >>>>> >>>>>>We don't want the ss modulation to show up in the DC outputs as ripple >>>>>>or anything audible. >>>>>. >>> >>>>>RF wideband filtering, inductors.. capacitors... >>>>> >>>> >>>>The jitter pattern needs to create spectral spreading at high >>>>frequencies but not change averages at low frequencies. There might be >>>>some math involved. >>> >>>Yes I'v heard about maaz >>>I do not see many tennis players use math to calculate how to move and where to point the ball. >>>Would take too long. >> >>Given the speed of measurable electrical nerve impulses, most sports >>should be impossible. Recognizing an image, one of millions, in >>milliseconds is even more improbable. >> >>Something else is going on. > >In massive parallel: Fit, extrapolate, intercept. > >Joe Gwinn Even massive parallel has layers of logic, and chemistry is slow. I suspect that the nerve impulses that we can detect electrically are not the real story. It is assumed that the pulse timing conveys the data, which makes no sense.