 |
Search Sci.Electronics.Basics |
|
|
|
|
|
|
 |
|
|
Sci.Electronics.Basics -> Questions about equivalents of audio/video and digital/analog.
There are 304 messages in this thread.
You are currently looking at messages 180 to 200.
|
Author: Bob MyersDate: 12:53 21-08-07
|
|
"Floyd L. Davidson" <floyd@apaflo.com> wrote in message
news:874pitiy5f.fld@apaflo.com...
> Look up the definition of "quantization" again. It simply
> makes no difference. If an analog signal is quantized, the
> result is a digital signal. That is by definition, and you
> cannot escape that with mumbo-jumbo and faulty logic.
But of course, you haven't yet even posted a definition
which says that, let alone provided any reasoning which
would support such a definition.
Bob M.
|
|
|
|
Author: Bob MyersDate: 12:56 21-08-07
|
|
"Floyd L. Davidson" <floyd@apaflo.com> wrote in message
news:87zm0lhjj0.fld@apaflo.com...
>>Note, for example, that an analog current is quantized in units
>>of the charge on the electron.
>
> No, in fact it is not. Electrons do not necessarily all move
> at the same speed...
Ummmm - now you have a problem with the definition
of the units used to quantify current? An Ampere (the
standard unit of current) is defined as 1 Coulomb of charge
passing a given point per second, and the Coulomb is most definitely
defined in terms of the fundamental unit of charge (which equals
the magnitude of charge on a single electron). Nothing in this
requires all the electrons to be moving at the same speed,
any more than a flow of 10 gallons/hour of water requires that
I move each ounce of water at the same rate.
Geeze, Floyd, which is it? Either definitions are important,
or they're not.
Bob M.
|
|
|
|
Author: iswDate: 13:04 21-08-07
|
|
In article <876439hg3o.fld@apaflo.com>,
floyd@apaflo.com (Floyd L. Davidson) wrote:
> You don't appear to understand that the limited set of values makes
> it digital, by definition. PERIOD.
So, does that make quantum physics "digital"?
Isaac
|
|
|
|
Author: Scott SeidmanDate: 13:28 21-08-07
|
|
"Bob Myers" <nospamplease@address.invalid> wrote in news:faf4co$co5$1
@usenet01.boi.hp.com:
>
> Really? Then I shouldn't be able to find any standards
> organizations which use a conflicting definition, right?
The nicest thing about standards is that there are so many from which to
choose.
--
Scott
Reverse name to reply
|
|
|
|
Author: Floyd L. DavidsonDate: 13:38 21-08-07
|
|
"Bob Myers" <nospamplease@address.invalid> wrote:
>"Floyd L. Davidson" <floyd@apaflo.com> wrote in message
>news:87veb9hjev.fld@apaflo.com...
>
>>>
>>>"Analog" != "continuous," even though most commonly
>>>"analog" signals are also continuous in nature.
>>
>> Analog signals are by *definition* continous.
>
>Nonsense. You don't believe it is possible to sample
>an "analog" signal and have it remain analog?
I didn't say that an analog signal is always present. I
said the value representation is by definition
continuous.
If you cannot understand these simple things without it
being spelled out in detail what they mean...
>> You have misunderstood what that means though. The
>> analog value of a signal is continuous,
>
>Well, THAT certainly makes it clearer....
And of course you had no idea until now that that is
what we've always been talking about, right?
The fact that this sort of trivial detail has to be
explained to you certainly indicates just how uninformed
you are on this topic. You should not be arguing with
anyone about it, but asking questions and learning.
>Since you seem to be so hung up on definitions, Floyd,
>try this one on for size:
>
>Continuous: unchanged or uninterrupted: continuing
>without changing, stopping, or being interrupted in space
>or time.
Now apply that to the value of an analog signal, and you
too can have a good understanding of the definitions
used to distinguish between analog and digital.
Please note that a non-existent signal cannot be either
analog or digital. Hence when you try to weasel out of
valid definitions for a signal by claiming that pulsed
samples are not continuous, it might seem cute to you,
but it is trivially childish.
The definition does not say that the signal's
*existence* is continuous, it says that the *value* of
the signal is continuous for analog while digital has a
finite set of discrete values.
>Note that this does not say anything at all about the range
>of possible values being "continuous" (which is what you
>seem to be trying to say in the above).
True, it doesn't say anything at all about the
definitions of digital and analog, so one wonders why
you would bring up such a childish and trivial attempt
at obfuscation. Other than the obvious fact that it has
finally dawned on you that the definitions provided are
in fact rigorously correct...
--
Floyd L. Davidson <http://www.apaflo.com/floyd_davidson>;
Ukpeagvik (Barrow, Alaska) floyd@apaflo.com
|
|
|
|
Author: Floyd L. DavidsonDate: 13:55 21-08-07
|
|
"Bob Myers" <nospamplease@address.invalid> wrote:
>"Floyd L. Davidson" <floyd@apaflo.com> wrote in message
>news:87mywlki1d.fld@apaflo.com...
>
>>>>>>
>>>>>>If you quantize the magnitude, it is digital. That is
>>>>>>by definition.
>>>No, you haven't. You merely have a signal at a set of discrete levels.
>>
>> Sheesh! That *is*, by definition a digital signal.
>
>Really?
Do you need the definitions repeated? If the values are
discrete and from a finite set, that is defined as digital.
Crawl into a corner and deny standard definition of terms
if you like, but it means that nothing you say about the
topic is credible.
>Suppose I show you an oscilloscope screen which
>is displaying a single line of video, which happens to be
>carrying an 8-level gray-scale pattern. It clearly shows
>a set of discrete levels.
It shows no such thing. You cannot tell from looking at
it how many levels it could possibly have. You can't
actually tell (just from looking at it) how many levels
it has at any given instant.
The scope simply does not tell you that sort of
information. It only shows you what currently exists,
and over a period of time you can (perhaps) get an idea
of at least some of the possible range of variations.
But you *cannot* tell if the variations are or are not
discrete or continuous.
Only if you already know absolutely what the format is,
can you determine what part of the format you are
seeing.
>Further, since this video happened
>to be created by a D/A converter with only three bits at
>the input (our video generator was built on the cheap!), those
>are the ONLY levels this signal may exhibit. Is this a
>"digital" signal?
You have said nothing that makes it necessary one or the
other.
>> Bullshit son. Look it up. I've provided you with
>> quotes from an authoritative reference, twice now. You
>> don't have to take my word for it, that *is* the agreed
>> technical definition of the term.
>
>Ah, Floyd - argument from authority again, huh?
Ah, Bob... that is very clearly a *valid* appeal to
authority. The quotes are indeed from an expert,
virtually *all* experts agree with what that
particular one said, and the quotes were in context and
meant to be what I claim they are. Look it up in any
reference work on logic, and you'll find that is
precisely what makes such an argument valid.
You, on the other hand, have a totally worthless
opinion, with nothing at all to support it. And that's
why you continue to make such gross errors!
--
Floyd L. Davidson <http://www.apaflo.com/floyd_davidson>;
Ukpeagvik (Barrow, Alaska) floyd@apaflo.com
|
|
|
|
Author: Floyd L. DavidsonDate: 13:58 21-08-07
|
|
"Arny Krueger" <arnyk@hotpop.com> wrote:
>"Bob Myers" <nospamplease@address.invalid> wrote in message
>news:faf16o$96g$1@usenet01.boi.hp.com...
>>
>> "Floyd L. Davidson" <floyd@apaflo.com> wrote in message
>> news:87mywlki1d.fld@apaflo.com...
>>
>>>>>>>
>>>>>>>If you quantize the magnitude, it is digital. That is
>>>>>>>by definition.
>>>>No, you haven't. You merely have a signal at a set of discrete levels.
>>>
>>> Sheesh! That *is*, by definition a digital signal.
>>
>> Really? Suppose I show you an oscilloscope screen which
>> is displaying a single line of video, which happens to be
>> carrying an 8-level gray-scale pattern. It clearly shows
>> a set of discrete levels.
>
>Well it shows what was once a set of discrete levels. Since it is now in the
>analog domain, there will be rise time, overshoot, tilt, simple inaccuracy,
>and etc. .
That has no relevance to whether it represents a discrete set
of values.
>> Further, since this video happened
>> to be created by a D/A converter with only three bits at
>> the input (our video generator was built on the cheap!), those
>> are the ONLY levels this signal may exhibit. Is this a
>> "digital" signal?
>
>It's an analog signal that represents something that was once quantized.
It could also be a digital signal. You simply cannot
tell from looking at a scope.
>>> Bullshit son. Look it up. I've provided you with
>>> quotes from an authoritative reference, twice now. You
>>> don't have to take my word for it, that *is* the agreed
>>> technical definition of the term.
>
>The definitions are fine, it is the misapplication of them that sticks.
Oh, are we back to the idea that the NTIA had never heard of
PCM when they came up with those definitions?
In fact, *you* are not able to apply them, as is obvious from
what you said above.
--
Floyd L. Davidson <http://www.apaflo.com/floyd_davidson>;
Ukpeagvik (Barrow, Alaska) floyd@apaflo.com
|
|
|
|
Author: Piergiorgio SartorDate: 14:20 21-08-07
|
|
Floyd L. Davidson wrote:
>> No, you haven't. You merely have a signal at a set of discrete levels.
>
> Sheesh! That *is*, by definition a digital signal.
Maybe you should go back to look at the root of the word "analogue".
It is the same as "analogy".
And, usually, it means that a physical entity is represented (by
analogy) by an other physical entity.
For example, a mercury thermometer uses the "length", a physical
entity, to represent the "temperature", an other physical entity.
The analogy is "inches" ("millimeters") to "degrees".
A pressure gauge uses "angle degrees" as analogy for "pascal".
So it does an analog volt meter.
On the other side we have digital, where a number is used to
represent a physical entity. And this is a just plain number, so
the signal represented has no physical energy, only statistical.
A digital thermometer shows directly the temperature as a number.
All this has nothing to do with sampled, discreet, quantized,
continuous an so on.
Sometimes the analogy is one to one (length for length, for example),
but the concept is the same.
bye,
--
piergiorgio
|
|
|
|
Author: Bob MyersDate: 14:32 21-08-07
|
|
"Floyd L. Davidson" <floyd@apaflo.com> wrote in message
news:87r6lxhilz.fld@apaflo.com...
>>Except that "absence of noise" is a condition which
>>doesn't exist, even in theory.
>
> Apparenlty Claude Shannon didn't agree with you on that.
And apparently you don't understand what was meant in
the above.
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? If so, please show the
error.
This does not prevent a noise-free channel from being IMAGINED,
and used as the basis for a mathematical analysis, which is
what Shannon did. But Shannon most definitely did NOT
expect any such thing to be realized, and fully understood
why it could not be.
Have you even read Shannon's paper? In section V (27),
Shannon makes virtually the same statement I gave earlier
re the notion of "infinite" levels:
"This means that to transmit the output of a continuous
source with *exact recovery* [emphasis Shannon's]
at the receiving point requires, in general, a channel of
infinite capacity (in bits per second). Since ordinarily
channels have a certain amount of noise, and therefore
a finite capacity, exact transmission is impossible."
Gee, here's another puzzler for you - throughout his
paper, Shannon discusses channel capacity in terms of
"bits per second." Does this mean that his work is
applicable only to digital systems? If not, why not?
Bob M.
|
|
|
|
Author: Bob MyersDate: 14:36 21-08-07
|
|
"Nobody" <nobody@nowhere.com> wrote in message
news:pan.2007.08.21.00.33.47.453000@nowhere.com...
>> It is most certainly quantized; it cannot take
>> on any values between adjacent output levels,
>> which are themselves separated by one "LSB" step
>> size.
>
> That doesn't make it quantised.
To borrow a notion from our mutual friend Floyd,
who appears to be infallible in terms of definitions
and such, that is the very definition of quantized!
>
>> What makes something "digital" is the representation
>> of information by numeric values ("digits"), or their equivalent,
>> as opposed to its representation by analogous variations
>> in some other quantity (which is "analog"). This is the
>> only definition which consistently makes sense.
>
> Whether or not a signal is "digital" depends upon what you intend to do
> with it. A PCM signal conveying the digits 01010101... is digital; a
> square wave generated within an audio synthesiser isn't, even if the
> signals are identical.
Precisely! It is purely a matter of intent at the transmitting
end, of how the information conveyed by the signal in
question is SUPPOSED to be interpreted. The two signals
described above - actually, this could be considered as one
signal, since the two ARE "identical" - carry vastly different
meanings, depending solely on the intent of the transmitter.
Bob M.
|
|
|
|
Author: Bob MyersDate: 14:38 21-08-07
|
|
"Radium" <glucegen1@gmail.com> wrote in message
news:1187656673.019577.232410@z24g2000prh.googlegroups.com...
> On Aug 20, 8:47 am, "Bob Myers" <nospample...@address.invalid>
wrote:
>
>> You can also
>> reduce the temporal frequency in the case of motion video.
>
> That's what I was talking about. Reducing the temporal frequency of
> the video w/out low-pass filtering or increasing the length of the
> movie.
And THAT is simply using a lower frame rate in the first
place. No "filtering" involved, per se, but it can have some
undesired results in terms of the portrayal of motion, etc..
Bob M.
|
|
|
|
Author: Bob MyersDate: 14:39 21-08-07
|
|
"Radium" <glucegen1@gmail.com> wrote in message
news:1187657907.358531.30270@q3g2000prf.googlegroups.com...
> Actually I don't want other parts to be unchanged. What I would like
> is the temporal frequencies [of all parts of the video] to be
> decreased but without decreasing the speed of the video signal.
And here's where you need to be clearer, and very likely
do some more thinking about what you're after - exactly
what do you mean by "speed" of the video signal?
Bob M.
|
|
|
|
Author: Bob MyersDate: 14:48 21-08-07
|
|
"Floyd L. Davidson" <floyd@apaflo.com> wrote in message
news:877inobxek.fld@apaflo.com...
>>> You have misunderstood what that means though. The
>>> analog value of a signal is continuous,
>>
>>Well, THAT certainly makes it clearer....
>
> And of course you had no idea until now that that is
> what we've always been talking about, right?
This is just priceless. Floyd, you really need to have
your Sarcasm Detector looked at because, son, it
ain't a-workin' at all...
Bob M.
|
|
|
|
Author: Bob MyersDate: 14:52 21-08-07
|
|
|
|
|
|
Author: Arny KruegerDate: 15:00 21-08-07
|
|
"Floyd L. Davidson" <floyd@apaflo.com> wrote in message
news:87tzqsahx5.fld@apaflo.com...
> "Arny Krueger" <arnyk@hotpop.com> wrote:
>>"Bob Myers" <nospamplease@address.invalid> wrote in message
>>news:faf16o$96g$1@usenet01.boi.hp.com...
>>>
>>> "Floyd L. Davidson" <floyd@apaflo.com> wrote in message
>>> news:87mywlki1d.fld@apaflo.com...
>>>
>>>>>>>>
>>>>>>>>If you quantize the magnitude, it is digital. That is
>>>>>>>>by definition.
>>>>>No, you haven't. You merely have a signal at a set of discrete
levels.
>>>>
>>>> Sheesh! That *is*, by definition a digital signal.
>>>
>>> Really? Suppose I show you an oscilloscope screen which
>>> is displaying a single line of video, which happens to be
>>> carrying an 8-level gray-scale pattern. It clearly shows
>>> a set of discrete levels.
>>
>>Well it shows what was once a set of discrete levels. Since it is now in
>>the
>>analog domain, there will be rise time, overshoot, tilt, simple
>>inaccuracy,
>>and etc. .
>
> That has no relevance to whether it represents a discrete set
> of values.
>
>>> Further, since this video happened
>>> to be created by a D/A converter with only three bits at
>>> the input (our video generator was built on the cheap!), those
>>> are the ONLY levels this signal may exhibit. Is this a
>>> "digital" signal?
>>
>>It's an analog signal that represents something that was once quantized.
>
> It could also be a digital signal. You simply cannot
> tell from looking at a scope.
>
>>>> Bullshit son. Look it up. I've provided you with
>>>> quotes from an authoritative reference, twice now. You
>>>> don't have to take my word for it, that *is* the agreed
>>>> technical definition of the term.
>>
>>The definitions are fine, it is the misapplication of them that sticks.
>
> Oh, are we back to the idea that the NTIA had never heard of
> PCM when they came up with those definitions?
This response is irrelevant to what I said.
I get it. You can't read.
|
|
|
|
Author: Floyd L. DavidsonDate: 15:10 21-08-07
|
|
"Bob Myers" <nospamplease@address.invalid> wrote:
>"Floyd L. Davidson" <floyd@apaflo.com> wrote in message
>news:87ir79hghp.fld@apaflo.com...
>> It wasn't analog until you ran it through an analog amplifier.
>
>More nonsense.
>
>Again, the ONLY definitions of "analog" and "digital"
>which make any sense treat these as distinctions in
>the form of information encoding being used. If I
>run EITHER a "digital" or "analog" signal through an
>amplifier, what comes out can still be interpreted (the
>information recovered from the signal) ONLY if the
>encoding intent is understood and the proper decoding
>applied.
I'll be damned, you *finally* got *something* right!
Did you go back and actually read what I said, or did
you learn this somewhere else? Regardless, the above
supports *exactly* what I've been saying, and I do hope
that you have begun to make the connection.
After being passed through an analog amplifier, the data
has a totally different set of values than it did within
the digital system (the output of the digital system has
both sets, but once it enters an analog channel the digital
values are generally, though not always, lost), and it can
be applied to an analog transducer (such as a speaker)
with the desired effects.
>A serial stream of digital data still makes sense, whether
>the amplitude assigned to the "1" or "true" state is
>0.1V, 1V, 10V, or 100 kV. But it makes sense
>ONLY when interpreted AS a serial stream of bits.
Exactly. It is the *information* carried that
determines what is digital and what is analog. Others
have claimed that looking at it with a scope is a way to
determine which, but that is not true. A digital signal
has discrete values (whether that is represent by 0.1v
or 100Kv) from a finite set. An analog signal has a
continuous range of values. It is the values of the
*data* that make a difference, not voltage levels, phase
shifts, or whatever.
The fact that voltage can and does get varied over a
continuous range of voltages means *nothing*; but if
that continuous range of voltages represents a finite
set of data values it is a digitial signal and if it
represents a continuous set of data values it is an
analog signal.
>Similarly, an analog representation of, say, video makes
>sense only if interpreted AS "analog". No matter how
>"digital-ish" it might look, if you try to interpret THIS
>signal as a "digital" stream, you'll get gibberish.
Well, if you aren't just paroting back to me everything
I've been telling you, and now claiming it isn't what
you denied at every turn of the way!
>Floyd, you would be well advised to stop treating your
>"definitions" as though they were somehow handed
>down by God, and instead try to employ arguments
>that are actually based in something sensible.
You just agreed, and stated, that they are correct. I
use them correctly, and have from the beginning of this
discussion without fail.
You keep wandering all over the map because you simply
do not understand how it applies to more than a minimal
set of circumstances, apparently.
>> The NTIA is an authority, and MilStd specifications are
>> also authoritative. That is the reason I cited them.
>> And the *fact* is that you have not and cannot cite any
>> authoritative standards body that does not agree with
>> them.
>
>Neither of these - and for that matter, NO standards body
In fact, those two are, for these definitions, valid
authorities. You have not and cannot come up with
anyone who is credible that does not agree with them.
>- is an Infallible Source of Absolute Truth, and no standard
>should be looked at as a substitute for good ol' basic
>theory and experimentation.
And when you do your own homespun theorizing and come up
with *wrong* answers, it is ridiculous for you to claim
the standard definitions used by virtually everyone else
are wrong instead of you.
>This is the fundamental flaw
>with any argument "from authority": wrong is wrong, no matter
>who writes it down on a piece of paper.
And Bob Myers is *wrong*. You can claim otherwise all
you like, but when you disagree with every authority
there is on the definitions of basic fundamental terms,
it is abject *foolishness*.
>God knows I've
>spent way more than enough time in my career working
>with various standards organizations (in fact, I am currently
>chairing one fairly well-known such group), including both
>"industry" and "government" efforts, and I can tell you from
>long and painful experience that simply because something
>appears in a standards document does not make it correct.
>With the right people paying close attention, these documents
>can often turn out pretty darn good - but they should NEVER
>EVER be used as a substitute for some actual thought and
>understanding of the subject matter at hand.
That's a great deal of hand waving there Bob. You are
in fact making an invalid appeal to authority! You are
not an expert, and other experts do not agree with you.
Your logic is invalid.
Then you go on too make another basic logical mistake.
The fact that some Standards have been in error would
not suggest that all Standards are in error. You cannot
cite (nebulous and unspecified) errors in other
standards as a proof that those definitions are an
error.
--
Floyd L. Davidson <http://www.apaflo.com/floyd_davidson>;
Ukpeagvik (Barrow, Alaska) floyd@apaflo.com
|
|
|
|
Author: Bob MyersDate: 15:19 21-08-07
|
|
"Floyd L. Davidson" <floyd@apaflo.com> wrote in message
news:87lkc4aelf.fld@apaflo.com...
> Did you go back and actually read what I said, or did
> you learn this somewhere else? Regardless, the above
> supports *exactly* what I've been saying, and I do hope
> that you have begun to make the connection.
I've said it all along, Floyd; if you want to see where I said
it even earlier, I could refer you to my book...
>>A serial stream of digital data still makes sense, whether
>>the amplitude assigned to the "1" or "true" state is
>>0.1V, 1V, 10V, or 100 kV. But it makes sense
>>ONLY when interpreted AS a serial stream of bits.
>
> Exactly. It is the *information* carried that
> determines what is digital and what is analog.
Gee, that's funny. Earlier you were claiming that
simply "quantizing" a signal was sufficient to make
something "digital." You were also talking about
"digital" and "analog" channels - so I would have to
assume, from this, that you are of the belief that
channels can somehow "know" the nature of the
information they are carrying, and thus become
"digital" or "analog" themselves.
> The fact that voltage can and does get varied over a
> continuous range of voltages means *nothing*; but if
> that continuous range of voltages represents a finite
> set of data values it is a digitial signal and if it
> represents a continuous set of data values it is an
> analog signal.
Oh, too bad! You were SO close to having it right, and
then your preconceived notions again got in the way.
It has NOTHING TO DO with whether the range is
continuous or not, it has EVERYTHING to do with
how the signal is to be interpreted. My monitor has an
"analog" input, which is so named because it "knows"
that if it's presented with a video signal level twice that
of this other level over here, it should produce twice
the luminance ("gamma" effects ignored for simplicity).
This has nothing to to with how many intermediate levels
there may be between these two, or even if there are
ANY intermediate levels between the two - solely with
the fact that the levels themselves are direct "analogs"
(gee, there's that word again) to the desired luminance
level.
> Well, if you aren't just paroting back to me everything
> I've been telling you, and now claiming it isn't what
> you denied at every turn of the way!
I would love to see you show me where I denied ANY
of the above.
> That's a great deal of hand waving there Bob. You are
> in fact making an invalid appeal to authority! You are
> not an expert, and other experts do not agree with you.
And your sole rationale for saying that I am not an
"expert" is: I disagree with you! Wow, that's an amazingly
logical position, isn't it?
> Then you go on too make another basic logical mistake.
> The fact that some Standards have been in error would
> not suggest that all Standards are in error.
You need a course in basic logic. I did not argue that "the fact
that some standards are in error suggests that all standards
are in error." What I argued was the fact that some standards
are in error suggests that other standards may also be in error,
and cannot be assumed to be correct simply because they are
"standards."
Bob M.
|
|
|
|
Author: Floyd L. DavidsonDate: 15:40 21-08-07
|
|
Don Bowey <dbowey@comcast.net> wrote:
>"Floyd L. Davidson" <floyd@apaflo.com> wrote:
>> Don Bowey <dbowey@comcast.net> 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.
--
Floyd L. Davidson <http://www.apaflo.com/floyd_davidson>;
Ukpeagvik (Barrow, Alaska) floyd@apaflo.com
|
|
|
|
Author: Jerry AvinsDate: 16:08 21-08-07
|
|
Floyd L. Davidson wrote:
...
> You don't appear to understand that the limited set of values makes
> it digital, by definition. PERIOD.
I don't recall your being explicit about the origin or basis for that
definition.
US cash transactions are quantized to the nearest penny. Does that make
money digital?
Jerry
--
Engineering is the art of making what you want from things you can get.
¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯
¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯
|
|
|
|
Author: Floyd L. DavidsonDate: 16:09 21-08-07
|
|
|
|
|
|
|
|
|
|
|
Contact | Electronic Portal
|
|
|
