Congrates on a great design. Glad it worked so well for their app and us (tax payers). We all benefit when we share knowledge in a collective way.
Wonder what LIGO will do now/next that Einstein's theory has been proven true via measurement.
THx-RNMarsh
Wonder what LIGO will do now/next that Einstein's theory has been proven true via measurement.
THx-RNMarsh
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I hear LHC has moved beyond Higg's boson this is really a great time for science.
Now they make it much more sensitive and start detecting locations of these waves. There will be at least 4 sites on earth and if the LISA pathfinder works a space network as well. LISA is another bogglesome bit of precision dohickery.
ESA Science & Technology: LISA Pathfinder
I was never Stoic enough for those sort of projects so I left aerospace.
A thousand feet multimode??? The control guys at work used multi mode only for runs less than about 200 feet. Longer than that, they told me that the dispersion problem made them go single mode.
All 31 timing runs are 400 feet long, all are single mode, I had to put all into the tray in places that were below the power conductors so as to prevent length modulation by temperature..they had to keep transit time matching in the 60 picosecond range.
John
We've been doing R&D for the LHC upgrade focus magnets for about 5 years now. I think the upgrade will be in a decade or so.
While ITER is still being built, 6 consortiums are actually scaling size down to roughly a meter in size (the ITER central solenoid is 10 meters tall, it's an internal component of the overall assembly), I suspect over unity fusion will happen there first (edit: "there" being one of the smaller machines, it seems that 12 tesla is a better field number for fusion, requiring 20 tesla at the conductors..a tad too much for a 10 meter by 3 meter solenoid.) One neat thing is, some of the internals will be made using laser 3-D sintering on a huge scale.
Japan is doing some really neat neutrino work using their JPARC ring.
The fate of the International Linear Collider is still unknown, proto focus magnets were built for that about 7 years ago.
Carbon 12 medical synchrotrons are starting to progress, I hope that goes fast, in the event I need it..
They're exploring the internal structure of the proton here, apparently there is a big "spin" problem, as they're probing to figure out where the spin comes from..
John
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This is all good advice..... I was responsible for LLNL's first R&D FO lab back in the day..... Our problem was when a nuclear 'device' went off, the radiation (X-ray et al) given off would darken the FO and reduce the signal and other characteristics which prevented accurate data collection. During that time multimode had less loss thus a lower power Xmit source could be used. A cost savings. Higher power sources like laser diodes would be used with single mode. Multimode is also easier to terminate et. But now that is somewhat easier and critical fiber alignments are not so hard to get from single mode.
I would see if you could go with single-mode but know that you will have to upgrade the hardware as well for long distance use. Over-all higher cost but better performance for long runs. And you will have to match lengths where timing is of concern.
THx-RNMarsh
Where did I mention a rate??
John
edit: did you mean your application rate? If so, how did you spec the cable based on the digital requirements? Here, the control guys are just using the multimode for communication, and for timing it's single.
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No, not you ,,, them. Of course you would.....talking about Sound reinforcement uses/stadium runs.
Also..... depending on the particle, the spin will produce a gavitational ripple freq. .. unique to that particle. Spin wobble would be found to be from the particle path asymmetry with other particle(s).
Write that down. memorize it.
Thx-RNMarsh
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Ah, I didn't see you turn your head towards Pennsylvania.😉
Well, publish...I can say I knew who said it "years ago"...
They're colliding polarized proton beams here. Varying the spin, up, down, none, in various combo's. Interesting stuff.
John
Bob Katz has done some work that is fairly recent (2013) regarding jitter. Note also what he says about AES. The tests are good and he explains in a clear way. Seems that add weight to my own limited T&M. Also, power supply quality affect on jitter is more important than I thought before..... an area DIY can easily upgrade.
Jitter - Digital Domain: CD Mastering | Mastered for iTunes | Audio Mastering | Blu-Ray Mastering
THx-RNMarsh
Jitter - Digital Domain: CD Mastering | Mastered for iTunes | Audio Mastering | Blu-Ray Mastering
THx-RNMarsh
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I don't see why a DAC would clip at full scale digital input, with the exception of lousy design.
Am I right that the gain structure problem is when nonlinear interpolation comes up with a value higher than full scale output? And that to avoid this, I need to set my digital source to -3db (or some other fundamentals-derived number)?
Actually, I'm using a software resampler to resample everything to 192KHz, so my DAC doesn't badly interpolate anything (that's the theory anyways). So, should I set the resampler input to -3db?
Also what is the real likelihood that interpolation will produce such high peaks when playing music? Doesn't the frequency have to be near Fs/2 as well as being near full scale?
Am I right that the gain structure problem is when nonlinear interpolation comes up with a value higher than full scale output? And that to avoid this, I need to set my digital source to -3db (or some other fundamentals-derived number)?
Actually, I'm using a software resampler to resample everything to 192KHz, so my DAC doesn't badly interpolate anything (that's the theory anyways). So, should I set the resampler input to -3db?
Also what is the real likelihood that interpolation will produce such high peaks when playing music? Doesn't the frequency have to be near Fs/2 as well as being near full scale?
Isn't the issue that the reconstruction filter can come up with an analog value higher than expected with 0dB full scale, and then clipping on the analog side?
Jan
Jan
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