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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 200 to 220.
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Author: Bob MyersDate: 16:42 21-08-07
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"Floyd L. Davidson" <floyd@apaflo.com> wrote in message
news:878x84abum.fld@apaflo.com...
> "Bob Myers" <nospamplease@address.invalid> wrote:
>>"Floyd L. Davidson" <floyd@apaflo.com> wrote in message
>>news:87ir79khtk.fld@apaflo.com...
>>>>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:
You keep thinking people are asking for definitions,
when in fact they are asking what terms mean
TO YOU. In other words, do you have any real
*understanding* of the meanings or implications of
what you're saying, or are you merely here to parrot
the words of others without actually bothering to
understand them?
Bob M.
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Author: Jim KelleyDate: 16:55 21-08-07
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Nobody wrote:
>
> The circuit which performs the quantisation *is* an analogue to digital
> converter.
There's a difference between quantization and quantification. A sample
and hold, for example, quantizes an analog signal. It is considered
quantized because a signal might now be represented as a series of
sampled levels rather than a continuously varying level. But the held
samples are not digitized until they have been quantified, i.e. a
number has been assigned to each sample that is ratiometric with the
analog quantity being digitized. In the digital domain, the signal is
comprised of a series of numbers each of which represents a discrete
(quantized) analog value.
> An important property of practical digital components is that they
> regenerate the signal. If you define e.g. the range 0V-2V as "zero" and
> 3V-5V as "one", then each component will accept outputs which are near
the
> edges of the range and produce outputs which are further from the edges
> (i.e. less ambiguous).
That is a property of binary logic circuits. The two states may
literally be representative of on and off rather than one and zero.
There may be nothing at all 'digital' about such circuits.
jk
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Author: Floyd L. DavidsonDate: 17:10 21-08-07
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"Bob Myers" <nospamplease@address.invalid> wrote:
>"Floyd L. Davidson" <floyd@apaflo.com> wrote in message
>news:873aydkfr4.fld@apaflo.com...
>
>>
>> What you need to get straight is that it is not *my*
>> definition. It is the *standard* technical definition
>> recognized by virtually *every* standards organization.
>
>Really? Then I shouldn't be able to find any standards
>organizations which use a conflicting definition, right?
You cannot have have not.
>But ANY argument from authority always takes a back
>seat to an argument from evidence and reason, since
>those arguments directly undermine item (1) above.
What evidence and what reason? You have no evidence,
and your reasoning is not authoritative.
I deleted all of your wallowing and weaseling.
The standard definitions stand.
--
Floyd L. Davidson <http://www.apaflo.com/floyd_davidson>;
Ukpeagvik (Barrow, Alaska) floyd@apaflo.com
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Author: Floyd L. DavidsonDate: 17:10 21-08-07
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Author: Floyd L. DavidsonDate: 17:13 21-08-07
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"Bob Myers" <nospamplease@address.invalid> wrote:
>"Floyd L. Davidson" <floyd@apaflo.com> wrote in message
>news:87tzqtj09u.fld@apaflo.com...
>> You can repeat that all you like, but you are wrong
>> every time you do.
>>
>> By *definition* it is a digital signal.
>>
>> quantization:
>> A process in which the continuous range of values
>> of an analog signal is sampled and divided into
>> nonoverlapping (but not necessarily equal)
>> subranges, and a discrete, unique value is assigned
>> to each subrange.
>
>Funny, I don't see the word "digital" in there. Perhaps
You did see "discrete, unique value" right. Bingo.
>you could point it out? No one is arguing that
>"quantized" does not mean the above - but you seem
>to be arguing that "quantized" is precisely equivalent
>to "digital," while none of the definitions you provide
>say that.
For people who cannot reason...
--
Floyd L. Davidson <http://www.apaflo.com/floyd_davidson>;
Ukpeagvik (Barrow, Alaska) floyd@apaflo.com
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Author: Floyd L. DavidsonDate: 17:16 21-08-07
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Don Bowey <dbowey@comcast.net> wrote:
>On 8/20/07 11:30 PM, in article 87y7g5cscy.fld@apaflo.com, "Floyd L.
>Davidson" <floyd@apaflo.com> wrote:
>
>> Don Bowey <dbowey@comcast.net> wrote:
>>> On 8/20/07 10:19 PM, in article 87odh1ea6x.fld@apaflo.com, "Floyd L.
>>> Davidson" <floyd@apaflo.com> wrote:
>>>
>>>> Don Bowey <dbowey@comcast.net> wrote:
>>>>> On 8/20/07 8:14 PM, in article 874pitfujh.fld@apaflo.com,
"Floyd L.
>>>>> Davidson" <floyd@apaflo.com> wrote:
>>>>>>>>
>>>>>>>> Of course if you then run that digital PAM signal
through virtually
>>>>>>>> any analog channel, it no longer has a limited set of
values...
>>>>>>>
>>>>>>> Including a two foot piece of cable, or two inches with a
small cap.
>>>>>>
>>>>>> Nope. It would take a fair sized cap.
>>>>>>
>>>>>> Keep in mind that that is *exactly* what a V.90 modem puts on a
>>>>>> regular twisted pair telephone cable, and it works just fine
for
>>>>>> a couple miles at least, sometimes even much farther.
>>>>>>
>>>>>> And that signal is digital, and is processed as a digital
signal
>>>>>> by the receiving modem.
>>>>>
>>>>> Digital data CSUs and T1 transmitter line signals are digital and
look
>>>>> similar to distorted square waves. An all 1's signal looks like a
>>>>> distorted
>>>>> sinewave .
>>>>
>>>> Your point is? (Besides the poor description? They
>>>> don't look like distorted square waves. The look like
>>>> only slightly distorted sine waves!)
>>>
>>> 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?
Or are you just missing something....
>I posted the DSX-1 template, and a representative pulse within it (MS Word),
>on a.b.s.e. The pulse shown was from equipment that generated the pulse
>using an analog method. As you can see from the envelope, other pulses,
>specifically, those generated digitally, could be much more "square" if
>given enough processing time.
>
>Numeric points for plotting the template to a spreadsheet are available if
>anyone wants them, but I will be away until next Saturday.
--
Floyd L. Davidson <http://www.apaflo.com/floyd_davidson>;
Ukpeagvik (Barrow, Alaska) floyd@apaflo.com
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Author: Floyd L. DavidsonDate: 17:17 21-08-07
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Author: Bob MyersDate: 17:24 21-08-07
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"Floyd L. Davidson" <floyd@apaflo.com> wrote in message
news:87odh08ugt.fld@apaflo.com...
> "Bob Myers" <nospamplease@address.invalid> wrote:
>>"Floyd L. Davidson" <floyd@apaflo.com> wrote in message
>>news:873aydkfr4.fld@apaflo.com...
>>
>>>
>>> What you need to get straight is that it is not *my*
>>> definition. It is the *standard* technical definition
>>> recognized by virtually *every* standards organization.
>>
>>Really? Then I shouldn't be able to find any standards
>>organizations which use a conflicting definition, right?
>
> You cannot have have not.
I'll wait to respond until that can be re-stated in something
resembling standard English.
Bob M.
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Author: Bob MyersDate: 17:27 21-08-07
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"Floyd L. Davidson" <floyd@apaflo.com> wrote in message
news:87d4xg8ubb.fld@apaflo.com...
>>Funny, I don't see the word "digital" in there. Perhaps
>
> You did see "discrete, unique value" right. Bingo.
So "digital" = "discrete," as long as we accept your
claim, not backed by ANY definition or reasoning,
that it does?
>
>>you could point it out? No one is arguing that
>>"quantized" does not mean the above - but you seem
>>to be arguing that "quantized" is precisely equivalent
>>to "digital," while none of the definitions you provide
>>say that.
>
> For people who cannot reason...
Oh, NOW it's not about the definitions, it's about
"reason," eh? Fine - reason away. It will be, at the
very least, a refreshing change.
Did you learn this flip-flopping technique ("It's all
about the definitions!" "No, it's not actually IN the
definitions, it's all about reason!") from any
politicians you'd care to name?
Bob M.
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Author: Bob MyersDate: 17:29 21-08-07
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"Jim Kelley" <jwkelley@uci.edu> wrote in message
news:fafjrj$5vo$1@news.service.uci.edu...
> There's a difference between quantization and quantification. A sample and
> hold, for example, quantizes an analog signal. It is considered quantized
> because a signal might now be represented as a series of sampled levels
> rather than a continuously varying level. But the held samples are not
> digitized until they have been quantified, i.e. a number has been assigned
> to each sample that is ratiometric with the analog quantity being
> digitized. In the digital domain, the signal is comprised of a series of
> numbers each of which represents a discrete (quantized) analog value.
Oh, gee, Jim, you obviously just don't get it, either, or
so I am expecting Floyd to claim. Gee, and you
SOUNDED like an "authority," too....:-)
The above was very nicely stated, by the way.
Bob M.
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Author: Floyd L. DavidsonDate: 17:36 21-08-07
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"Bob Myers" <nospamplease@address.invalid> wrote:
>"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?
So you have show that the in practice part is true, and
I have show that the in theory part was wrong. A noiseless
channel can exist in theory (not in practice). It is
a very usefule theory to study too.
--
Floyd L. Davidson <http://www.apaflo.com/floyd_davidson>;
Ukpeagvik (Barrow, Alaska) floyd@apaflo.com
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Author: timepixdcDate: 18:04 21-08-07
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In article <fafb3q$i4d$1@usenet01.boi.hp.com>,
"Bob Myers" <nospamplease@address.invalid> 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,
> This does not prevent a noise-free channel from being IMAGINED
Theory? Imagination? Can't have the first without the second.
X-no archive
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Author: Bob MyersDate: 18:11 21-08-07
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Author: Don BoweyDate: 18:14 21-08-07
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On 8/21/07 12:40 PM, in article 87d4xgad6e.fld@apaflo.com, "Floyd L.
Davidson" <floyd@apaflo.com> wrote:
> 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.
Gosh, after all that I guess I should be impressed.......... But........ I'm
not. I wonder why.
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Author: Don BoweyDate: 18:22 21-08-07
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Author: Don BoweyDate: 18:47 21-08-07
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On 8/21/07 2:16 PM, in article 878x848u7c.fld@apaflo.com, "Floyd L.
Davidson" <floyd@apaflo.com> wrote:
> Don Bowey <dbowey@comcast.net> wrote:
>> On 8/20/07 11:30 PM, in article 87y7g5cscy.fld@apaflo.com, "Floyd L.
>> Davidson" <floyd@apaflo.com> wrote:
>>
>>> Don Bowey <dbowey@comcast.net> wrote:
>>>> On 8/20/07 10:19 PM, in article 87odh1ea6x.fld@apaflo.com, "Floyd
L.
>>>> Davidson" <floyd@apaflo.com> wrote:
>>>>
>>>>> Don Bowey <dbowey@comcast.net> wrote:
>>>>>> On 8/20/07 8:14 PM, in article 874pitfujh.fld@apaflo.com,
"Floyd L.
>>>>>> Davidson" <floyd@apaflo.com> wrote:
>>>>>>>>>
>>>>>>>>> Of course if you then run that digital PAM signal
through virtually
>>>>>>>>> any analog channel, it no longer has a limited set
of values...
>>>>>>>>
>>>>>>>> Including a two foot piece of cable, or two inches with
a small cap.
>>>>>>>
>>>>>>> Nope. It would take a fair sized cap.
>>>>>>>
>>>>>>> Keep in mind that that is *exactly* what a V.90 modem puts
on a
>>>>>>> regular twisted pair telephone cable, and it works just
fine for
>>>>>>> a couple miles at least, sometimes even much farther.
>>>>>>>
>>>>>>> And that signal is digital, and is processed as a digital
signal
>>>>>>> by the receiving modem.
>>>>>>
>>>>>> Digital data CSUs and T1 transmitter line signals are digital
and look
>>>>>> similar to distorted square waves. An all 1's signal looks
like a
>>>>>> distorted
>>>>>> sinewave .
>>>>>
>>>>> Your point is? (Besides the poor description? They
>>>>> don't look like distorted square waves. The look like
>>>>> only slightly distorted sine waves!)
>>>>
>>>> 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?
>
> 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.
>
>> I posted the DSX-1 template, and a representative pulse within it (MS Word),
>> on a.b.s.e. The pulse shown was from equipment that generated the pulse
>> using an analog method. As you can see from the envelope, other pulses,
>> specifically, those generated digitally, could be much more "square"
if
>> given enough processing time.
>>
>> Numeric points for plotting the template to a spreadsheet are available if
>> anyone wants them, but I will be away until next Saturday.
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Author: AnthonyR.Date: 20:35 21-08-07
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"Radium" <glucegen1@gmail.com> wrote in message
news:1187579079.834795.176100@l22g2000prc.googlegroups.com...
> On Aug 19, 7:47 pm, Jerry Avins <j...@ieee.org> 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.
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Author: Floyd L. DavidsonDate: 21:29 21-08-07
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Author: Jerry AvinsDate: 21:34 21-08-07
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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.
¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯
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Author: Floyd L. DavidsonDate: 23:32 21-08-07
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Don Bowey <dbowey@comcast.net> wrote:
>"Floyd L. Davidson" <floyd@apaflo.com> 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) floyd@apaflo.com
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