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#282
Posted to sci.electronics.basics,rec.video.desktop,comp.dsp,rec.audio.tech,rec.photo.digital
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Questions about equivalents of audio/video and digital/analog.
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#283
Posted to sci.electronics.basics,rec.video.desktop,comp.dsp,rec.audio.tech,rec.photo.digital
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Questions about equivalents of audio/video and digital/analog.
"Radium" wrote in message oups.com... On Aug 19, 7:47 pm, Jerry Avins wrote: Radium wrote: Other than the microphone [obviously], why does there need to be any moving parts? If a digital audio device can play audio back without any moving parts, why can't an analog audio device be designed to do the same? Describe a motion-free process of recording and playing back. Cutting grooves on a disk or magnetizing a moving tape both involve motion. The iPod is motion-free yet it's still able to record and playback. Those Nintendo Entertainment System cartridges were able to playback without any motion. The device below is *not* analog. It uses sampling so its digital: http://www.winbond-usa.com/mambo/content/view/36/140/ I'm curious to why there are no purely-analog devices which can record, store, and playback electric audio signals [AC currents at least 20 Hz but no more than 20,000 Hz] without having moving parts. Most of those voice recorders that use chips [i.e. solid-state] are digital. Analog voice recorders, OTOH, use cassettes [an example of "moving parts"]. It's this simple: nobody has invented a way. I doubt than anyone ever will. If you know how, communicate with me privately. I don't know how but I guessing that it involves the analog equivalent of Flash RAM [if re-writing is desired] or the analog equivalent of Masked-ROM [if permanent storage is desired]. I suspect the simple answer is space required. For example you needed a large reel to reel tape to fit a song, but an iPod uses digital audio (compressed) so it can fit so many more 1's and 0's onto the same size magnetic tape that would have only held a little actual analog signal. See? So if someone did make a solid state analog recorder it probably require too many memory chips to be practical. I don't know specs but 8mb that hold tons of music on an iPod probably only hold a few seconds of actual analog frequency data. IMHO AnthonyR. |
#284
Posted to sci.electronics.basics,rec.video.desktop,comp.dsp,rec.audio.tech,rec.photo.digital
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Questions about equivalents of audio/video and digital/analog.
Don Bowey wrote:
On 8/21/07 1:09 PM, in article , "Floyd L. Davidson" wrote: "Bob Myers" wrote: "Floyd L. Davidson" wrote in message ... The signal can be reconverted to an analogue one later by a D to A. It's best to call that a quasi-analog signal... Why? What does that mean, EXACTLY, that I've given you the URL for a glossary of terms, why don't you use it? Here are some others: http://www.atis.org/tg2k/ http://www.itu.int/sancho/index.asp http://www.carrieraccessbilling.com/...glossary-a.asp http://www.faxswitch.com/Definitions/ isn't already conveyed (and conveyed more accurately) by other, more appropriate terms? What additional information does this "quasi-analog" nonsense bring to the party? Quasi-Analog Signal - A digital signal that has been converted to a form suitable for transmission over a specified analog channel. Gobbledegook. And you claimed to have worked in transmission engineering? Whooosh... -- Floyd L. Davidson http://www.apaflo.com/floyd_davidson Ukpeagvik (Barrow, Alaska) |
#285
Posted to sci.electronics.basics,rec.video.desktop,comp.dsp,rec.audio.tech,rec.photo.digital
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Questions about equivalents of audio/video and digital/analog.
Don Bowey wrote:
(snip) Your reply is incomplete. * "ISDN is Integrated Services Digital Network." Right * "It is a digital signal in all respects...." Right * "...using what is called 2B1Q encoding on a customer Basic Rate Interface loop. That is 2 Binary 1 Quaternary meaning there are two binary bits encoded in each symbol using 4 possible voltage levels." Incomplete, therefore wrong. Those voltage levels go through analog electronics on the way to the other end. Hopefully the other end detects the appropriate voltage levels at the right time. It is voltage and current, not bits, that travel down the wire. There is also a Primary Rate ISDN, which is a DS1 rate and which uses the AMI line code, modified by B8ZS. One end of a Primary Rate channel may be in a Central Office or both ends may be at a customer premises. On its way to a V.90 modem the signal originates on an ISDN channel, goes through one D/A converter, and then on to the V.90 modem. The modem can synchronously decode the voltages and figure out which bits went into the ISDN line. That process doesn't work if there are more than one D/A conversions on the line. -- glen |
#286
Posted to sci.electronics.basics,rec.video.desktop,comp.dsp,rec.audio.tech,rec.photo.digital
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Questions about equivalents of audio/video and digital/analog.
AnthonyR. wrote:
... So if someone did make a solid state analog recorder it probably require too many memory chips ... What kind of chips hold analog signals? How do their storage capacities compare to digital storage? Jerry -- Engineering is the art of making what you want from things you can get. ¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯ ¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯ ¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯ |
#287
Posted to sci.electronics.basics,rec.video.desktop,comp.dsp,rec.audio.tech,rec.photo.digital
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Questions about equivalents of audio/video and digital/analog.
"Bob Myers" wrote:
"Floyd L. Davidson" wrote in message ... video system, mentioned earlier. The levels of the video signal are ANALOGOUS to the desired luminance level, and that's all it takes to be "analog." That is not true. See the definition of analog data and digital data. The definitions according to yourself and your selected "authorities"? Yet again? How about some reasoning, instead, for a change? Every authority uses the same definitions. I've shown you a list of URL's where, if you had looked, you would have found exactly the same definition from each different source. I note that even though you deny it and claim there are other definitions, you can't find even one that is different. See Shannon, "A Mathematical Theory of Communication," section V (27). Have someone help you with the big words, as needed. When you're finished, find us an example of a noiseless channel, and demonstrate to us what you're saying. You clearly need some help understanding it... Shannon discussed the theory of digital channels with and without noise. Shannon never used the word "digital," though, and used the term "bits" simply because that is the commonly-used unit of information (in ANY system), per information and Wrong. Shannon didn't use the word "digital" because it was not a popular term for what he was working with until *after* he published his work and the study of digital signals became popular. Nobody except Shannon was, at that time, thinking in terms of digitizing data, signals, channels, and everything else. (Okay, not totally true, as people like Alec Reeves certainly was too...) Shannon didn't use the work "bit" because of any common useage! John Tukey, a co-worker of Shannon's at Bell labs had coined the term "bit" as a short form for "binary digit", only the year before Shannon first used it in a 1948 paper. It fit their needs, and later became popular with others too. In fact, as the "commonly-used unit of information (in ANY system)", Claude Shannon was the very *first* person to use the term! He certainly did not use it because any common useage, given it had been used only by one other person and then with a slightly different meaning. communications theory as it was established at the time The theory had not been established at the time. It was Shannon's work that started "Information Theory". While Hartley and Nyquist had theorized about various things, and demonstrated certain effects, Claude Shannon was the one who mathematically *proved* them, thus providing various theorums for future research. (and is still in use today). Given that you've admitted to not being an authority in the field, I wouldn't expect that One thing that is quit obvious Bob is that I am significantly more authoritative in the field of communications than you are. Not that that is saying much... you understood that before, so I'm more than happy to give you this chance to learn. You're welcome. It would have been nice if you had known what you were talking about before you again spouted nonsense. He defined it as "a discrete channel will mean a system whereby a sequence of choices from a finite set ... can be transmitted ..." Right - he defined a DISCRETE channel. The only Yes. You'll remember that the definition of a digital signal is that it has discrete values. Guess what Shannon discussed... a channel for transmission of discrete values. The way we describe that today is "digital", and Shannon's "discrete channel" is exactly what a digital channel is. tie between "discrete" and "digital" appears to exist solely in your own mind, since your cherished definitions of That is one of the most hilarious things you've said in all of this. You flat deny the very reason that these terms exist, ignore all of their history, and proclaim yourself an expert. Astounding. "quantized" also unfortunately neglect to use the word "digital" at any time. Shannon did NOT refer to either "digital" or "analog" channels at all. Of course he didn't. And in 1948 nobody at all was using those terms to describe a communications channel, of any kind. That useage did not become popular until after Shannon's papers were published. And it should be obvious to anyone who can read English that the standard definitions of "digital" an "analog" (as applied to communications, transmission systems, signals, data, etc. etc) was selected to precisely match what Shannon's paper analyzed, and was taken directly from those papers. (Heh, you wanted evidence and reasoning, well, there you are. The evidence and the reason. He then discussed the theory of analog channels, which began with, "We now consider the case where the signals or the messages or both are continuously variable, in contrast with the discrete nature assumed heretofore." Wrong again. He discussed the theory of CONTINUOUS channels, which is how they are consistently referenced in his paper. In fact, the term "analog/analogue" does not appear even once in Shannon's paper. Exactly. The terms digital and analog only became popular *after* Shannon's paper was published, and as noted above the standardized definitions are specifically intended to reference the papers that Shannon published. "Analogous" appears a grand total of six times, each time with the clearly-accepted meaning of "similar to," as opposed to refering to any specific class of signals. Similarly, "digital" does not appear at all. Shannon correctly did not make any distinction between "analog" and "digital" encoding in terms of information capacity or content, as his theorems apply to any and all systems. Nobody else was using those term in that way at the time. It was *because* of Shannon's work that such terms came into existance *after* Information Theory became a popular topic for research. Clearly his definitions were consistent with those that have been cited. Of course that again is just another horrible appeal to authority... ;-) Or it would have been, had Shannon actually provided any such definitions. Too bad he didn't. Too bad you didn't realize the direct connection! Are you actually so brass as to claim that the "discrete channel" term that Shannon used is not precisely describing what we call a "digital channel" today? Or that his "continuous channel" is not what we call an "analog channel"? I don't mean something about the same, close, or relatively... I mean the terms are *exactly* identical, in all respects. -- Floyd L. Davidson http://www.apaflo.com/floyd_davidson Ukpeagvik (Barrow, Alaska) |
#288
Posted to sci.electronics.basics,rec.video.desktop,comp.dsp,rec.audio.tech,rec.photo.digital
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Questions about equivalents of audio/video and digital/analog.
Don Bowey wrote:
"Floyd L. Davidson" wrote: Have you looked at a DSX-1 envelope lately? Yes. I've got the specs right here! :-) Literally, I have had a graph on my web site for several years now that I drew up to illustrate something I wrote once upon a time http://www.apaflo.com/floyd_davidson/t1pulse.jpg (snip) The pulse for which you provided the link, is not DSX-1, because it will not fit within the DSX-1 envelope. Really? Has the standard changed? Not that I know of. ANSI T1.403 does good. Want to argue with it? Why would I argue with it. The link provided shows what ANSI T1.403 says it is. It *does* fit within the standard DSX-1 pulsemask (which is conveniently available from just about every manufacturer of test equipment). Or are you just missing something.... I don't believe so. On the other hand, I inquired to you about the DSX-1 envelope, and you replied with a link to a waveform you drew, which has only a loose connection to DSX-1. It appears you might be missing something. You claimed to have worked with transmission engineering? Did you sweep floors, or what? -- Floyd L. Davidson http://www.apaflo.com/floyd_davidson Ukpeagvik (Barrow, Alaska) |
#289
Posted to sci.electronics.basics,rec.video.desktop,comp.dsp,rec.audio.tech,rec.photo.digital
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Questions about equivalents of audio/video and digital/analog.
Don Bowey wrote:
On 8/21/07 2:33 PM, in article , "Floyd L. Davidson" wrote: glen herrmannsfeldt wrote: Arny Krueger wrote: (snip) Sure I can. If I look at a line between two V-90 modems, I can immediately see that it is an analog line. It may be carrying audio or video, but thats about the data that is being carried, not the signal that I'm looking at. I don't believe V.90 works that way. That is, you can't connect two V.90 modems together that way. You cannot connect two subscriber modems end to end and use v.90 protocols. But you can use to provider end modems and get v.90 protocols running in both direction, and in fact if the line is good enough it can be made to run a 64 Kbps. The answer end of a V.90 connection must be an ISDN line, usually a It must be digital. ISDN is one possibility, but not the only one. primary rate line with 24 channels. The result is that there is only one A/D and D/A conversion between the two end points. Exactly. The "A" part of that is a digital PAM signal. If it goes through and extra CODEC, the data is scrambled. You may say that an ISDN line is an analog line since you can measure the voltage on the wire as a function of time. I won't try to argue either way on that one. That would be an absurd claim. ISDN is Integrated Services Digital Network. It is a digital signal in all respects, using what is called 2B1Q encoding on a customer Basic Rate Interface loop. That is 2 Binary 1 Quaternary meaning there are two binary bits encoded in each symbol using 4 possible voltage levels. Your reply is incomplete. Your reply is incomplete too. There are *many* things about ISDN that neither of us have mentioned. Of course neither of us had or have any intention of writing a book about ISDN. * "ISDN is Integrated Services Digital Network." Right * "It is a digital signal in all respects...." Right * "...using what is called 2B1Q encoding on a customer Basic Rate Interface loop. That is 2 Binary 1 Quaternary meaning there are two binary bits encoded in each symbol using 4 possible voltage levels." Incomplete, therefore wrong. It isn't wrong. I specifically said that I was describing BRI, and that is because it is the *only* digital format defined by ISDN. There is also a Primary Rate ISDN, which is a DS1 rate and which uses the AMI line code, modified by B8ZS. One end of a Primary Rate channel may be in a Central Office or both ends may be at a customer premises. You just described a DS1, which is *not* defined by ISDN. Why don't you also describe DS0's, DS2's, DS3's and what you have for breakfast? They are just as related to ISDN as is a DS1. -- Floyd L. Davidson http://www.apaflo.com/floyd_davidson Ukpeagvik (Barrow, Alaska) |
#290
Posted to sci.electronics.basics,rec.video.desktop,comp.dsp,rec.audio.tech,rec.photo.digital
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Questions about equivalents of audio/video and digital/analog.
glen herrmannsfeldt wrote:
Don Bowey wrote: (snip) Your reply is incomplete. * "ISDN is Integrated Services Digital Network." Right * "It is a digital signal in all respects...." Right * "...using what is called 2B1Q encoding on a customer Basic Rate Interface loop. That is 2 Binary 1 Quaternary meaning there are two binary bits encoded in each symbol using 4 possible voltage levels." Incomplete, therefore wrong. Those voltage levels go through analog electronics on the way to the other end. Hopefully the other end detects the appropriate voltage levels at the right time. It is voltage and current, not bits, that travel down the wire. It is a digital signal, it provides a digital channel, and it is a digital service. Voltage is analog, but there is no analog communications channel involved, no analog data, and no analog service. There is also a Primary Rate ISDN, which is a DS1 rate and which uses the AMI line code, modified by B8ZS. One end of a Primary Rate channel may be in a Central Office or both ends may be at a customer premises. On its way to a V.90 modem the signal originates on an ISDN channel, It might. It might not. goes through one D/A converter, and then on to the V.90 modem. Note that the "D/A converter" is a CODEC, and in fact is used as a digital encoder. Input is digital, an do so is the output (in the direction of the subscriber). The modem can synchronously decode the voltages and figure out which bits went into the ISDN line. That process doesn't work if there are more than one D/A conversions on the line. Because of the fact that it is digital, not analog. In the uplink direction it is an analog signal (v.34 protocol), and can pass through additional codecs. -- Floyd L. Davidson http://www.apaflo.com/floyd_davidson Ukpeagvik (Barrow, Alaska) |
#291
Posted to sci.electronics.basics,rec.video.desktop,comp.dsp,rec.audio.tech,rec.photo.digital
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Questions about equivalents of audio/video and digital/analog.
Don Bowey wrote:
On 8/21/07 12:40 PM, in article , "Floyd L. Davidson" wrote: Don Bowey wrote: "Floyd L. Davidson" wrote: Don Bowey wrote: Do you know of any telco that actually uses them today? If a loop is long enough, and there is no pair-gain facility available, it gets an "E" type repeater. If that isn't an analog repeater nothing is. Of course I suppose it is possible they are still being used where *you* live. But I don't know of any telco in all of Alaska that has used an E repeater in the last 30-40 years. In particular, in the last 10-20 years that would be totally unacceptable. I didn't leave my telco job until the end of 94. At which times they were still in use, but there was talk of using gain within the switching So you don't know of any telco that uses them today. I assume you were also using mechanical switching there too... ;-) It is sort of difficult for me to imagine that sort of environment, as Alaska was fully digital when the rest of the country had only gone 33% digital. By the mid-1980 the only mechanical switches left in Alaska were owned by the military, and they were gone by 1990. Still, I don't think anyone *ever* used E type repeaters in Alaska, but I could be wrong on that. machines. It wouldn't surprise me if that is being done now, being a simple process. In any case, there are loops that require gain to meet minimum requirements. Also, we had a tariff that provided additional gain (for a price) where feasible. The general design paradigm used now is to put "remotes" at multiple strategic sites and control them all from one digital switch. Of course all of these are trunked together, and the whole idea is to prevent long loops while also requiring administration of only a single digital switch. That was a basic design decision made for telco's by the vendors, back in the late 80's or early 90's. It was enforced with system pricing! Nortel (NTI at the time), for example, simply made the software for a digital switch (actually, the long term use and maintenance of the software) far more expensive than installing remotes. It became uneconomical to have two switches in any jurisdiction where it was possible to deactivate one and replace it and move forward with remotes. By the mid-1990's all of NTI's customer base had moved in that direction. My concerns were not just for where "I lived." I was on the Transmission Engineering staff, and we had 14 states with which to be concerned. My concern was only the State of Alaska... which is of course the size of 20% of the entire Lower-48. Gosh, after all that I guess I should be impressed.......... But........ I'm not. I wonder why. Because it is *way* over your head. -- Floyd L. Davidson http://www.apaflo.com/floyd_davidson Ukpeagvik (Barrow, Alaska) |
#292
Posted to sci.electronics.basics,rec.video.desktop,comp.dsp,rec.audio.tech,rec.photo.digital
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Questions about equivalents of audio/video and digital/analog.
Don Bowey wrote:
On 8/21/07 1:47 PM, in article , "glen herrmannsfeldt" wrote: Arny Krueger wrote: (snip) Sure I can. If I look at a line between two V-90 modems, I can immediately see that it is an analog line. It may be carrying audio or video, but thats about the data that is being carried, not the signal that I'm looking at. I don't believe V.90 works that way. That is, you can't connect two V.90 modems together that way. The answer end of a V.90 connection must be an ISDN line, usually a primary rate line with 24 channels. That is nonsense. ISDN has nothing to do with it. Any modern digital message trunk provides an identical channelizing process. True. (Aren't you the one who just tried to require a discription of ISDN to include specs for a DS1 though? Double standard?) The result is that there is only one A/D and D/A conversion between the two end points. Same as the Message Network. Wrong. Nothing restricts anything else in the network to *only* one set of A-D/D-A conversions. Everything else has a minimum of one, assuming a digital switch based line. You may say that an ISDN line is an analog line since you can measure the voltage on the wire as a function of time. What are you calling an ISDN line? The ds1 rate cable pairs? DS3 transport, Sonet, the analog channel that pops out of the terminal multiplexer? Good points all! -- Floyd L. Davidson http://www.apaflo.com/floyd_davidson Ukpeagvik (Barrow, Alaska) |
#293
Posted to sci.electronics.basics,rec.video.desktop,comp.dsp,rec.audio.tech,rec.photo.digital
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Questions about equivalents of audio/video and digital/analog.
On 8/21/07 6:29 PM, in article , "Floyd L.
Davidson" wrote: Don Bowey wrote: On 8/21/07 1:09 PM, in article , "Floyd L. Davidson" wrote: "Bob Myers" wrote: "Floyd L. Davidson" wrote in message ... The signal can be reconverted to an analogue one later by a D to A. It's best to call that a quasi-analog signal... Why? What does that mean, EXACTLY, that I've given you the URL for a glossary of terms, why don't you use it? Here are some others: http://www.atis.org/tg2k/ http://www.itu.int/sancho/index.asp http://www.carrieraccessbilling.com/...glossary-a.asp http://www.faxswitch.com/Definitions/ isn't already conveyed (and conveyed more accurately) by other, more appropriate terms? What additional information does this "quasi-analog" nonsense bring to the party? Quasi-Analog Signal - A digital signal that has been converted to a form suitable for transmission over a specified analog channel. Gobbledegook. And you claimed to have worked in transmission engineering? Whooosh... Don't be such an ass. A question was asked and I replied. If a signal is passed as analog, then it's analog; not blue analog or green analog, or sort of analog, or like analog. Calling something quasi-analog brings nothing to the table but gobbledegook. |
#294
Posted to sci.electronics.basics,rec.video.desktop,comp.dsp,rec.audio.tech,rec.photo.digital
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Questions about equivalents of audio/video and digital/analog.
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#295
Posted to sci.electronics.basics,rec.video.desktop,comp.dsp,rec.audio.tech,rec.photo.digital
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Questions about equivalents of audio/video and digital/analog.
"Floyd L. Davidson" wrote in message ... ....a lot more argument by vigorous assertion, the repetitive, monotonous bulk of which has been deleted. However, a couple of gems that just can't pass by unanswered: (and is still in use today). Given that you've admitted to not being an authority in the field, I wouldn't expect that One thing that is quit obvious Bob is that I am significantly more authoritative in the field of communications than you are. It would not appear to be all that obvious, in that you seem to be the only one here arguing your particular definitions - against fair number of people, including more than one person who IS clearly a recognized expert in the field. Right - he defined a DISCRETE channel. The only Yes. You'll remember that the definition of a digital signal is that it has discrete values. Wrong - YOU have asserted this repeatedly, and yet you continue to offer as "evidence" for this a definition that simply says that "quantized" signals have "discrete values," with no mention of the word digital at all outside of your own continued assertions. Well, to coin a phrase...DUH. That is one of the most hilarious things you've said in all of this. You flat deny the very reason that these terms exist, ignore all of their history, and proclaim yourself an expert. Astounding. Having to resort to out-and-out falsehoods, now? Please show any point in this discussion where I have "proclaimed myself an expert." I would hardly refer to your behavior here as "astounding," though. Pitiful, perhaps. Bob M. |
#296
Posted to sci.electronics.basics,rec.video.desktop,comp.dsp,rec.audio.tech,rec.photo.digital
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Questions about equivalents of audio/video and digital/analog.
On 8/21/07 8:32 PM, in article , "Floyd L.
Davidson" wrote: Don Bowey wrote: "Floyd L. Davidson" wrote: Have you looked at a DSX-1 envelope lately? Yes. I've got the specs right here! :-) Literally, I have had a graph on my web site for several years now that I drew up to illustrate something I wrote once upon a time http://www.apaflo.com/floyd_davidson/t1pulse.jpg (snip) The pulse for which you provided the link, is not DSX-1, because it will not fit within the DSX-1 envelope. Really? Has the standard changed? Not that I know of. ANSI T1.403 does good. Want to argue with it? Why would I argue with it. The link provided shows what ANSI T1.403 says it is. It *does* fit within the standard DSX-1 pulsemask (which is conveniently available from just about every manufacturer of test equipment). Or are you just missing something.... I don't believe so. On the other hand, I inquired to you about the DSX-1 envelope, and you replied with a link to a waveform you drew, which has only a loose connection to DSX-1. It appears you might be missing something. You claimed to have worked with transmission engineering? Did you sweep floors, or what? No, but I was a member of ANSI T1 Working Groups T1C1 and T1E1 and helped write ANSI T1.403 and other Standards. To phrase it in a technical language you MIGHT understand, your mind is an abysmal mess, and your behavior sucks. You enjoy the comfort of your ignorance and I'm certain this is how you will remain. |
#297
Posted to sci.electronics.basics,rec.video.desktop,comp.dsp,rec.audio.tech,rec.photo.digital
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Questions about equivalents of audio/video and digital/analog.
On 8/21/07 8:38 PM, in article , "Floyd L.
Davidson" wrote: Don Bowey wrote: On 8/21/07 2:33 PM, in article , "Floyd L. Davidson" wrote: glen herrmannsfeldt wrote: Arny Krueger wrote: (snip) Sure I can. If I look at a line between two V-90 modems, I can immediately see that it is an analog line. It may be carrying audio or video, but thats about the data that is being carried, not the signal that I'm looking at. I don't believe V.90 works that way. That is, you can't connect two V.90 modems together that way. You cannot connect two subscriber modems end to end and use v.90 protocols. But you can use to provider end modems and get v.90 protocols running in both direction, and in fact if the line is good enough it can be made to run a 64 Kbps. The answer end of a V.90 connection must be an ISDN line, usually a It must be digital. ISDN is one possibility, but not the only one. primary rate line with 24 channels. The result is that there is only one A/D and D/A conversion between the two end points. Exactly. The "A" part of that is a digital PAM signal. If it goes through and extra CODEC, the data is scrambled. You may say that an ISDN line is an analog line since you can measure the voltage on the wire as a function of time. I won't try to argue either way on that one. That would be an absurd claim. ISDN is Integrated Services Digital Network. It is a digital signal in all respects, using what is called 2B1Q encoding on a customer Basic Rate Interface loop. That is 2 Binary 1 Quaternary meaning there are two binary bits encoded in each symbol using 4 possible voltage levels. Your reply is incomplete. Your reply is incomplete too. There are *many* things about ISDN that neither of us have mentioned. Of course neither of us had or have any intention of writing a book about ISDN. * "ISDN is Integrated Services Digital Network." Right * "It is a digital signal in all respects...." Right * "...using what is called 2B1Q encoding on a customer Basic Rate Interface loop. That is 2 Binary 1 Quaternary meaning there are two binary bits encoded in each symbol using 4 possible voltage levels." Incomplete, therefore wrong. It isn't wrong. I specifically said that I was describing BRI, and that is because it is the *only* digital format defined by ISDN. There is also a Primary Rate ISDN, which is a DS1 rate and which uses the AMI line code, modified by B8ZS. One end of a Primary Rate channel may be in a Central Office or both ends may be at a customer premises. You just described a DS1, which is *not* defined by ISDN. Why don't you also describe DS0's, DS2's, DS3's and what you have for breakfast? They are just as related to ISDN as is a DS1. As I said before, but using different terms, you are an ignorant boob, and what's worse is, you're smug about it. I won't explain the many errors of your post this time, as I know it's a waste of time. |
#298
Posted to sci.electronics.basics,rec.video.desktop,comp.dsp,rec.audio.tech,rec.photo.digital
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Questions about equivalents of audio/video and digital/analog.
On 8/21/07 8:43 PM, in article , "Floyd L.
Davidson" wrote: Don Bowey wrote: On 8/21/07 12:40 PM, in article , "Floyd L. Davidson" wrote: Don Bowey wrote: "Floyd L. Davidson" wrote: Don Bowey wrote: Do you know of any telco that actually uses them today? If a loop is long enough, and there is no pair-gain facility available, it gets an "E" type repeater. If that isn't an analog repeater nothing is. Of course I suppose it is possible they are still being used where *you* live. But I don't know of any telco in all of Alaska that has used an E repeater in the last 30-40 years. In particular, in the last 10-20 years that would be totally unacceptable. I didn't leave my telco job until the end of 94. At which times they were still in use, but there was talk of using gain within the switching So you don't know of any telco that uses them today. I assume you were also using mechanical switching there too... ;-) It is sort of difficult for me to imagine that sort of environment, as Alaska was fully digital when the rest of the country had only gone 33% digital. By the mid-1980 the only mechanical switches left in Alaska were owned by the military, and they were gone by 1990. Still, I don't think anyone *ever* used E type repeaters in Alaska, but I could be wrong on that. machines. It wouldn't surprise me if that is being done now, being a simple process. In any case, there are loops that require gain to meet minimum requirements. Also, we had a tariff that provided additional gain (for a price) where feasible. The general design paradigm used now is to put "remotes" at multiple strategic sites and control them all from one digital switch. Of course all of these are trunked together, and the whole idea is to prevent long loops while also requiring administration of only a single digital switch. That was a basic design decision made for telco's by the vendors, back in the late 80's or early 90's. It was enforced with system pricing! Nortel (NTI at the time), for example, simply made the software for a digital switch (actually, the long term use and maintenance of the software) far more expensive than installing remotes. It became uneconomical to have two switches in any jurisdiction where it was possible to deactivate one and replace it and move forward with remotes. By the mid-1990's all of NTI's customer base had moved in that direction. My concerns were not just for where "I lived." I was on the Transmission Engineering staff, and we had 14 states with which to be concerned. My concern was only the State of Alaska... which is of course the size of 20% of the entire Lower-48. Gosh, after all that I guess I should be impressed.......... But........ I'm not. I wonder why. Because it is *way* over your head. I've changed my mind; I am impressed. You have impressed upon me the knowledge that you are much less than you would like to be. |
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Questions about equivalents of audio/video and digital/analog.
Jerry Avins wrote:
What kind of chips hold analog signals? How do their storage capacities compare to digital storage? Look at the ISD MicroTAD-16M. It can store 16 minutes of voice in 3840K memory cells, and a 4kHz sampling rate. It claims 100 year retention in the non-volatile memory cells, with 100,000 record cycles. It sounds like they use a memory cell similar to flash RAM, but store an analog voltage in that cell instead of only two states. -- glen |
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Questions about equivalents of audio/video and digital/analog.
Don Bowey wrote:
... A question was asked and I replied. If a signal is passed as analog, then it's analog; not blue analog or green analog, or sort of analog, or like analog. Calling something quasi-analog brings nothing to the table but gobbledegook. I have no idea which of all these posts to reply to (now mainly ad hominem, which seems sadly inevitable when a bunch of people who don't know each other go round in digital circles), so I am replying to this one. With the most profuse apologiees to Marshall McLuhan, the debate seems to be of this form (multiple-choice): Digital = * the medium * the message * both the medium and the message * neither the medium nor the message (select one - no interpolated choices allowed). And a question: does time series analysis (e.g. applying the FFT or wavelet analysis to daily stock price movements etc) employ Digital Signal Processing, Signal Processing, or Something Else? Richard Dobson |
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Questions about equivalents of audio/video and digital/analog.
On Wed, 22 Aug 2007 11:33:33 GMT, in 'rec.video.desktop',
in article Questions about equivalents of audio/video and digital/analog., Richard Dobson wrote: Don Bowey wrote: .. A question was asked and I replied. If a signal is passed as analog, then it's analog; not blue analog or green analog, or sort of analog, or like analog. Calling something quasi-analog brings nothing to the table but gobbledegook. I have no idea which of all these posts to reply to (now mainly ad hominem, which seems sadly inevitable when a bunch of people who don't know each other go round in digital circles), Digital circles??? Now we're really going off the deep end. Digital is a series of square waves. I know because I can see them on my 'scope. Think of TTL. "Digital circles" is a contradiction in terms. We can't communicate effectively if we don't all use the same lingo - with the same meanings attached to each key term. It is a well-known and well-documented fact that a digitally sampled circle, regardless of the sampling rate, *cannot* be converted back into a perfect analog circle. The mathematical proof of this was presented at a meeting of the Royal Society in 1681. Look it up. What's needed in this thread is less science fiction fantasy and more real hard science. so I am replying to this one. With the most profuse apologiees to Marshall McLuhan, the debate seems to be of this form (multiple-choice): Digital = * the medium * the message * both the medium and the message * neither the medium nor the message (select one - no interpolated choices allowed). And a question: does time series analysis (e.g. applying the FFT or wavelet analysis to daily stock price movements etc) employ Digital Signal Processing, Signal Processing, or Something Else? Richard Dobson -- Frank, Independent Consultant, New York, NY [Please remove 'nojunkmail.' from address to reply via e-mail.] Read Frank's thoughts on HDV at http://www.humanvalues.net/hdv/ |
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Questions about equivalents of audio/video and digital/analog.
In article ,
"Bob Myers" wrote: It is theoretically impossible for any real-world communications channel to be noise-free or possessed of infinite bandwidth. Do you disagree with this statement? It would appear that you disagree with your own statement since further down you write, What part of "real-world" (as opposed to "imaginary") in the above did you fail to comprehend? Before something can be developed it has to be imagined. Edison? Great imagination. You? Maybe not so much. From a recent (London) Daily Telegraph: "A pair of German physicists claim to have broken the speed of light - an achievement that would undermine our entire understanding of space and time. According to Einstein's special theory of relativity, it would require an infinite amount of energy to propel an object at more than 186,000 miles per second. However, Dr Gunter Nimtz and Dr Alfons Stahlhofen, of the University of Koblenz, say they may have breached a key tenet of that theory. The pair say they have conducted an experiment in which microwave photons - energetic packets of light - travelled "instantaneously" between a pair of prisms that had been moved up to 3ft apart. Being able to travel faster than the speed of light would lead to a wide variety of bizarre consequences." Your reliance on the "theoretically impossible" would have stopped such research before it started. You might even be the last person around that believes in phlogiston. Hard to tell. X-no archive |
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Questions about equivalents of audio/video and digital/analog.
glen herrmannsfeldt wrote:
Jerry Avins wrote: What kind of chips hold analog signals? How do their storage capacities compare to digital storage? Look at the ISD MicroTAD-16M. It can store 16 minutes of voice in 3840K memory cells, and a 4kHz sampling rate. It claims 100 year retention in the non-volatile memory cells, with 100,000 record cycles. It sounds like they use a memory cell similar to flash RAM, but store an analog voltage in that cell instead of only two states. So the audio is sampled but not digitized. Interesting! I'm downloading the data sheet now. Jerry -- Engineering is the art of making what you want from things you can get. ¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯ ¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯ ¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯ |
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Questions about equivalents of audio/video and digital/analog.
Frank wrote:
... Digital circles??? Now we're really going off the deep end. A hit already! Ah the power of words. Metaphors-r-us. Clearly I should have said "digital people going round in analogue circles". When ~everyone~ has lost all sense of perspective, the sense of humour is the first casualty. How about a "quantized circle" then - an octagon? Digital is a series of square waves. I know because I can see them on my 'scope. Think of TTL. Oh gosh, one of the standard waveforms on an analogue synth is the square wave. I think people were doing that before TTL was actually invented. Moog had PCM (meaning, variable duty-cycle) square waves coming out of his VCO in 1966, if not earlier. What about a sawtooth wave? That's a series of straight lines too. It is a well-known and well-documented fact that a digitally sampled circle, regardless of the sampling rate, *cannot* be converted back into a perfect analog circle. The mathematical proof of this was presented at a meeting of the Royal Society in 1681. Look it up. Interesting! In 1681 too! The first use of the word "digital" not connoting fingers. Exactly how does one sample a circle with ones fingers? This is fun! Richard Dobson |
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Questions about equivalents of audio/video and digital/analog.
"Richard Dobson" wrote in message k... Frank wrote: .. Digital circles??? Now we're really going off the deep end. A hit already! Ah the power of words. Metaphors-r-us. Clearly I should have said "digital people going round in analogue circles". When ~everyone~ has lost all sense of perspective, the sense of humour is the first casualty. Hmmmm...so could a person with no fingers still be considered a "digital person"? :-) Bob M. |
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Questions about equivalents of audio/video and digital/analog.
Richard Dobson wrote:
Frank wrote: .. Digital circles??? Now we're really going off the deep end. A hit already! Ah the power of words. Metaphors-r-us. Clearly I should have said "digital people going round in analogue circles". When ~everyone~ has lost all sense of perspective, the sense of humour is the first casualty. How about a "quantized circle" then - an octagon? Digital is a series of square waves. I know because I can see them on my 'scope. Think of TTL. Oh gosh, one of the standard waveforms on an analogue synth is the square wave. I think people were doing that before TTL was actually invented. Moog had PCM (meaning, variable duty-cycle) square waves coming out of his VCO in 1966, if not earlier. What about a sawtooth wave? That's a series of straight lines too. It is a well-known and well-documented fact that a digitally sampled circle, regardless of the sampling rate, *cannot* be converted back into a perfect analog circle. The mathematical proof of this was presented at a meeting of the Royal Society in 1681. Look it up. Interesting! In 1681 too! The first use of the word "digital" not connoting fingers. Exactly how does one sample a circle with ones fingers? This is fun! Oh Richard! I saw it as an excellent spoof. As you wrote, "the sense of humour [sic] is the first casualty. Speak for yourself! :-) Jerry -- Engineering is the art of making what you want from things you can get. ¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯ ¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯ ¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯ |
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Questions about equivalents of audio/video and digital/analog.
Bob Myers wrote:
"Richard Dobson" wrote in message k... Frank wrote: .. Digital circles??? Now we're really going off the deep end. A hit already! Ah the power of words. Metaphors-r-us. Clearly I should have said "digital people going round in analogue circles". When ~everyone~ has lost all sense of perspective, the sense of humour is the first casualty. Hmmmm...so could a person with no fingers still be considered a "digital person"? :-) Toes, my friend, toes. OT. Words to a Mozart horn concerto: Moses suppose his toeses are roses But Moses supposes erroneously ... Jerry -- Engineering is the art of making what you want from things you can get. ¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯ ¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯ ¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯ |
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Questions about equivalents of audio/video and digital/analog.
On 8/22/07 10:26 AM, in article
, "Richard Dobson" wrote: Frank wrote: .. Digital circles??? Now we're really going off the deep end. A hit already! Ah the power of words. Metaphors-r-us. Clearly I should have said "digital people going round in analogue circles". When ~everyone~ has lost all sense of perspective, the sense of humour is the first casualty. How about a "quantized circle" then - an octagon? Digital is a series of square waves. I know because I can see them on my 'scope. Think of TTL. Oh gosh, one of the standard waveforms on an analogue synth is the square wave. I think people were doing that before TTL was actually invented. Moog had PCM (meaning, variable duty-cycle) square waves coming out of his VCO in 1966, if not earlier. What about a sawtooth wave? That's a series of straight lines too. It is a well-known and well-documented fact that a digitally sampled circle, regardless of the sampling rate, *cannot* be converted back into a perfect analog circle. The mathematical proof of this was presented at a meeting of the Royal Society in 1681. Look it up. Interesting! In 1681 too! The first use of the word "digital" not connoting fingers. Exactly how does one sample a circle with ones fingers? While eating some Pi? This is fun! Richard Dobson |
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Questions about equivalents of audio/video and digital/analog.
On 8/22/07 10:31 AM, in article , "Bob
Myers" wrote: "Richard Dobson" wrote in message k... Frank wrote: .. Digital circles??? Now we're really going off the deep end. A hit already! Ah the power of words. Metaphors-r-us. Clearly I should have said "digital people going round in analogue circles". When ~everyone~ has lost all sense of perspective, the sense of humour is the first casualty. Hmmmm...so could a person with no fingers still be considered a "digital person"? :-) Quasi-digital? Bob M. |
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Questions about equivalents of audio/video and digital/analog.
Don Bowey wrote:
... Interesting! In 1681 too! The first use of the word "digital" not connoting fingers. Exactly how does one sample a circle with ones fingers? While eating some Pi? Cool. Or: delivering it through a letter-box one piece at a time. The question is then - how does the receiver know they have got the whole pi? Richard Dobson |
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Questions about equivalents of audio/video and digital/analog.
"Don Bowey" wrote in message ... On 8/22/07 10:31 AM, in article , "Bob Myers" wrote: "Richard Dobson" wrote in message k... casualty. Hmmmm...so could a person with no fingers still be considered a "digital person"? :-) Quasi-digital? No, he had fingers - wasn't that the guy who rang the bells at Notre Dame? Bob M. |
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Questions about equivalents of audio/video and digital/analog.
In article ,
Bob Myers wrote: Hmmmm...so could a person with no fingers still be considered a "digital person"? :-) Quasi-digital? No, he had fingers - wasn't that the guy who rang the bells at Notre Dame? Oh - you're thinking of the guy who developed the innovative feature in the Apple Macintosh windowing system... a little mini-window which would pop up, *mostly* block what was behind it, but let you move it out of the way if you really needed to. "Quasi-modal" dialog boxes... quite a coup for Apple, back in the Day. I understand that something similar has just shown up in Vista. -- Dave Platt AE6EO Friends of Jade Warrior home page: http://www.radagast.org/jade-warrior I do _not_ wish to receive unsolicited commercial email, and I will boycott any company which has the gall to send me such ads! |
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Questions about equivalents of audio/video and digital/analog.
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Questions about equivalents of audio/video and digital/analog.
On 8/22/07 11:41 AM, in article , "Bob
Myers" wrote: "Don Bowey" wrote in message ... On 8/22/07 10:31 AM, in article , "Bob Myers" wrote: "Richard Dobson" wrote in message k... casualty. Hmmmm...so could a person with no fingers still be considered a "digital person"? :-) Quasi-digital? No, he had fingers - wasn't that the guy who rang the bells at Notre Dame? Bob M. I think might have been his brother, Quasi-analog. |
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Questions about equivalents of audio/video and digital/analog.
Frank wrote:
(snip) Digital is a series of square waves. I know because I can see them on my 'scope. Think of TTL. I was thinking about this yesterday. In the easy cases digital signals can be NRZ coded. (That is, some voltage for a zero, a different voltage for a one.) The logic can be implemented simply with transistors that are either off or on. As distances get longer or frequencies get higher, analog techniques are needed in processing signals. Modulation methods are used to make it easier to separate out the signal from the noise, and to recover the clock that would otherwise be lost. At that point, it gets confusing whether the signal is "digital" or "analog." -- glen |
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Questions about equivalents of audio/video and digital/analog.
On Wed, 22 Aug 2007 11:06:46 -0500, timepixdc wrote:
.... Being able to travel faster than the speed of light would lead to a wide variety of bizarre consequences." Your reliance on the "theoretically impossible" would have stopped such research before it started. You might even be the last person around that believes in phlogiston. Hard to tell. Oh, I definitely believe in phlogiston - you can see tons of it on USENET any day of the week! ;-) To communicate faster than light, you have to interface with the Aether, which most people don't even believe exists! =:-O Cheers! Rich |
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Questions about equivalents of audio/video and digital/analog.
Rich Grise wrote:
... To communicate faster than light, you have to interface with the Aether, which most people don't even believe exists! =:-O Ah but they do! Now called the Higgs field; soon to be evidenced by the LHC, when they finally detect the God Particle. Until then it is just a particle of faith. Richard Dobson |
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Questions about equivalents of audio/video and digital/analog.
"Don Bowey" wrote in message ... They will never know, because Pi is endless. It is? Then how come they always are out of Pi when I want more? Bob M. |
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Questions about equivalents of audio/video and digital/analog.
On 8/22/07 2:22 PM, in article , "Bob Myers"
wrote: "Don Bowey" wrote in message ... They will never know, because Pi is endless. It is? Then how come they always are out of Pi when I want more? Bob M. Your market is using the wrong pi recipe/formulation? |
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Questions about equivalents of audio/video and digital/analog.
"Don Bowey" wrote in message ... It is? Then how come they always are out of Pi when I want more? Bob M. Your market is using the wrong pi recipe/formulation? Must be. People keep telling me pi are square, but all I see are the round ones... Bob M. |
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