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On Thu Aug 15 14:58:46 2024 Zen Cycle wrote:No one I've ever worked with in my 40+ years in this industry has ever been called 'sparky' except for the aforementioned intern. Your inane claim is about a valid as claiming I'm not an engineer because I don't call fiber optics light lines.On 8/15/2024 2:35 PM, cyclintom wrote:More proof that you're not an engineer.On Thu Aug 15 13:41:38 2024 Zen Cycle wrote:>On 8/15/2024 1:08 PM, cyclintom wrote:At least you know that "sparky" is a compliment to a real engineer.On Wed Aug 14 19:22:06 2024 zen cycle wrote:>>On 8/14/2024 3:35 PM, cyclintom wrote:>>
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Flunky just talks ahbout crap that he doesn't know about. Notice how
he could not answer how you measure the length of a wire
electronically? That's because he personally doesn't know how to use
an oscilloscope. Which comes as no
Or, It could be because Jeff answered it as well as I could so I didn't
feel it was worth commenting, but since you insist, here's how you test
cable length with _out_ using dedicated TDR equipment:
>
- Connect a pulse generator, an oscilloscope, and the cable under test
together with a T connector (Typically BNC, but adaptors may be required
depending on the equipment.
- set up a pulse generator to single pulse, starting with a 1 nS width,
5 V P-P.
- Set up the scope to trigger on the single pulse from the generator,
with the pulse from the generator being displayed at the extreme left of
the display.
- Adjust the time base of the oscilloscope until the reflected pulse
appears on the right side of the display while manually initiating the
pulse on the generator.*
- Longer cable lengths may make the returned pulse not quite
discernible. When the trigger pulse is no longer visible, increase the
pulse width until it is visible, then begin adjusting the time base
again until the reflected pules is visible (It may also be necessary to
increase the pulse amplitude).
- Once the reflected pulse is visible, measure the distance between the
trigger pulse and the reflected pulse on the scope as time delay (Hence
the term Time Domain Reflectometry).
- PLug this delay into the propagation delay value for the cable under
test, and do the math.
>
* setting up the generator to a repetitive pulse could prove problematic
in that the trigger pulse period my be shorter than the propagation
delay of the cable under test giving a confusing display. A competent
technician could manage it, but given the bizarre and completely
non-nonsensical method you described, it's well beyond your comprehension.
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I particularly liked the part about "BNC" because as we all know the connector type is important
It can be, depending on the application. When would you need an N-type?
or an F-type? Be specific.
>Because you don't know how to use an oscilloscope you can pretend that anyone wouldn't use repetitive pulses>
Pay attention sparky, I didn't write anyone "wouldn't use repetitive
pulses". I wrote "a repetitive pulse could prove problematic
>> in that the trigger pulse period my be shorter than the propagation
>> delay of the cable under test". In a manual set-up they wouldn't
unless they already had an idea of how long the cable under test was. A
repetitive pulse isn't require in any case. Is this why you were never
able to hold a job for more than a year?
>or that the actual pulse with (1 ns?) is important.>
I didn't say it was. I selected 1 nS as a matter of convenience. For
extremely long cables a 1 uS width is more advisable. The important
point is to have the pulse narrow enough such that the reflection isn't
obscured by the high level of the pulse.
>It is no surprise that you never got a real job.>
Says the guy who never had a job that lasted more than a year. Meanwhile
my resume includes ten years at HP/Agilent, ten years at Schneider
Electric, and ten years at my current position.
>
Still wanna play, sparky?
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no, it isn't, it's the name I give to a dog. In the 40 years I've been
in this industry I've never heard an engineer referred to as 'sparky'
except for a newbie hire who mis-wired a power supply and and blew up a
22000 uF 50V capacitor. It wasn't intended as a compliment.
>Diablo Research followed me around buying up all of the companies I developed products for until they got so rich they hired me full time.>
Cool story bro. too bad it's bullshit.
>That you think that R&D shyould be a permanent job at a single company shows how little you know about engineering.>
And where did I ever write that? I wrote that moving jobs every year is
a big red flag to an employer. Besides that, you're the one that wrote
"NO ONE EVER LEAVES HEWLETT-PACKARD!!!!!!".
>
If none of the engineers at HP ever left, I guess that means HP wasn't
really any good at anything, right sparky? Gawd you're an idiot.
>If you had a single thought in your head it would get lost in that vast void.>
Still waiting on the PWM cable testing reference, and here's a little
tidbit for you:
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Remember when you said TDR isn't used for fiber optic testing, and that
'light lines' is a commonly used term for fiber optic telecom cables?
This website discusses Optical TDR techniques, and at no point uses the
term "light lines" or PWM.
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https://www.flukenetworks.com/expertise/learn-about/otdr
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oh, and still waiting for that call from your lawyer for your libel
suit, you drunk-ass bitch.
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