Timeline for Electricity only flows in a complete circuit, so how does TDR (time domain reflectometery) work?
Current License: CC BY-SA 4.0
8 events
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| May 19, 2021 at 22:21 | comment | added | AnalogKid | Water pipes and HVAC ducts have a characteristic impedance. If you have a constant pressure source (fan) and a long duct (transmission line), the shape of the opening at the far end affects net air flow. Measure the air flow with the duct abruptly ending into a wide-open space, the equivalent of an open circuit. Now add a hyperbolically-curved flair to the end of the duct, like the curved body of a PA horn. This acts as an impedance matching transformer between the duct and the space. The airflow will increase. | |
| May 19, 2021 at 21:10 | comment | added | DKNguyen | @depwl9992 I think of it as a water pipe with different widths down the length and how smoothly water can be injected into the pipe. If it's a dead end (open-circuit, high-impedance) , you get water hammer. | |
| May 19, 2021 at 14:50 | comment | added | D Duck | Heaviside didn't just invent the math - he patented the coaxial cable! waveform.com/blogs/main/… physicstoday.scitation.org/do/10.1063/PT.5.030967/full | |
| May 18, 2021 at 23:26 | comment | added | depwl9992 | The characteristic impedance of a coax conductor has NEVER made sense to me in a physics sense. I just trust that it's a thing...and it means something and "oh, by the way, make sure the last device on the end of this is terminated actual matching resistor. Otherwise, you'll have ALL sorts of unwanted noise." To think that the guy invented the math to accommodate the phenomena is fascinating. Really need to jump back in and finish my degree after 10 years of practical work, and screwing around with all these "rules of thumb". | |
| May 18, 2021 at 13:20 | history | edited | AnalogKid | CC BY-SA 4.0 |
added 50 characters in body
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| May 18, 2021 at 9:37 | review | Suggested edits | |||
| May 18, 2021 at 12:23 | |||||
| May 18, 2021 at 4:03 | history | edited | Hearth | CC BY-SA 4.0 |
Fix spelling of Heaviside's name.
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| May 18, 2021 at 2:19 | history | answered | AnalogKid | CC BY-SA 4.0 |