In western Texas, in the USA, folks say that if you look far enough into the distance you can see the back of your head.
Thanks,
Chris
My colleague at UCLA years ago used to work for U. of Texas' McDonald Observatory, and said one night a very inebriated person was outside one of the domes shooting into the sky, and muttering "Star, your twinklin' days are over!"
To conceive of the concept of infinite space you only have to look at a Mobius strip. There is no inside or outside and no beginning or end. Perhaps the universe works in a similar manner and that is why we just can not conceive of an endless anything.
If you do not have a problem with Zero (0), then think of the finite size as moving into the zero(s) or place holder. -RNM
That's a good technique, as most of the time one is not trying to see the ~500MHz waveform directly anyway.
I used to have the active FET probe from Tek which had itself bandwidth to 900 MHz and push-on attentuator tips that reduced what was already a pretty low capacitance. They were helpful. Grounding was via a little spring slipover prong.
The business of high bandwidth probes for really HF stuff is now quite developed and intricate (and expensive!).
Best reading for control of interferance with can upset the normal operation of an amplifer/system can be found in the comprehensive technical volumes by Donald White Consultants: Electromagnetic Interference and Compatibility. Also, thier book on Shielding Design Methodology and Proceedures.
Other good sources of info are the IEEE standards and EU Directives on EMC.
Audio DIY problem solvers need to be aware that low Z and high Z circuits have to be handled differently... one produces electromagnetic interference and the other produce electrostatic interference, respectivly. Some situations can deal with both -- such as how a interconnect cable is constructed.... but you need to know the specifics of the system to be dealt with for the best solution. Its one of those variables that cause audiophiles to get varying results which drives lay and engineers crazy with inconsistant reports.
-Thx-RNM
Other good sources of info are the IEEE standards and EU Directives on EMC.
Audio DIY problem solvers need to be aware that low Z and high Z circuits have to be handled differently... one produces electromagnetic interference and the other produce electrostatic interference, respectivly. Some situations can deal with both -- such as how a interconnect cable is constructed.... but you need to know the specifics of the system to be dealt with for the best solution. Its one of those variables that cause audiophiles to get varying results which drives lay and engineers crazy with inconsistant reports.
-Thx-RNM
It may help, but may not help as well.
Anyway, it perfectly cuts bandwidth. 1k + 20pF makes 8MHz lowpass, and I showed 250MHz oscillations 😀😀😀
Grass greener, you are saying? 🙂
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And good riddance too. Love it. UTexas was honored for a while with the presence of John Wheeler, who said that there is only one electron, which bounces back and forth between the beginning and the end of time. Also explains why all electrons look alike.
Thanks,
Chris
No, I mean that opamps could not oscillate on 500 mHz, but probe tip could cause oscillations. 😀
Opamps not (but some can), but a diamond buffer built from fast transistors can happily oscillate at hundreds of MHz.
I do not want to swim into a usual pub-like discussion. The 250 MHz oscillations were a reality, documented.
I do not want to swim into a usual pub-like discussion. The 250 MHz oscillations were a reality, documented.
OT alert you can skip this
The eminent astronomer Jesse Greenstein, recruited at the last minute to replace Feynman for the one week, addressed the class and said how happy he was to be there. One little brat (and we were a nasty bunch of adolescent nerds) piped up: "Well, we wanted Feynman, but you'll have to do".
I reminded Harland Epps of this years later. He had forgotten (although he had chewed us out properly, immediately following), but noted that Greenstein had declined all invitations thereafter.
Greenstein had the unfortunate fate of missing the nature of QSOs as something other than faint blue stars with bizarre metallicity. Shortly thereafter Maarten Schmidt figured it out and made the cover of TIME. Schmidt was another guest of the Program that year, which amounted to 6 weeks of the most intense science and math I'd yet encountered. I came away from it deciding to do anything but, and focused on philosophy and music for a while.
I narrowly missed meeting Wheeler's collaborator Feynman in 1965 when I attended the Summer Science Program at the Thacher School in Ojai. He was due to guest-lecture there and was called to Washington at the last minute. I heard that at a previous year's program a student had asked RPF to talk about the notion that a positron was an electron travelling backwards in time. Feynman said "Well yeah! That's my theory!"😀
The eminent astronomer Jesse Greenstein, recruited at the last minute to replace Feynman for the one week, addressed the class and said how happy he was to be there. One little brat (and we were a nasty bunch of adolescent nerds) piped up: "Well, we wanted Feynman, but you'll have to do".
I reminded Harland Epps of this years later. He had forgotten (although he had chewed us out properly, immediately following), but noted that Greenstein had declined all invitations thereafter.
Greenstein had the unfortunate fate of missing the nature of QSOs as something other than faint blue stars with bizarre metallicity. Shortly thereafter Maarten Schmidt figured it out and made the cover of TIME. Schmidt was another guest of the Program that year, which amounted to 6 weeks of the most intense science and math I'd yet encountered. I came away from it deciding to do anything but, and focused on philosophy and music for a while.
Anatoliy - I remember them. I wonder why you guys never used any surface treatment for the transistor cases 😀
Please excuse what might be an uninformed question but might not those aberrations you show be exactly what the amps FB demands to keep the o/p cct clean when the o/p devices are switching ?
If the glitches didn't appear in the i/p cct perhaps they would show up on the o/p trace.
Just a thought
mike
I protest: Good electrons sound better than the other.
As a fine French humorist (Coluche) said: "Men born free and equal in rights. Some are more equal than the others."
Gold and silver have better electrons.
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Aren't they cute? 😀
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