Great thing that SMPS has made such improvement (flexibility to handle power line uglies, not that most are any better about being a "nice" load).
Why not use an active front end, then convert it to AC.
Similar to what's done on a VFD for large motors. It is expensive but it works.
Similar to what's done on a VFD for large motors. It is expensive but it works.
Only if it has a good PFC chip at the front end.
(had'ta get another acronym in there).
John
Ed,
with a 1000 foot cable, use a step function and a resistive load ranging from 4 to 150 ohms.
The settling time to 95% value will surprise you.
Also, the cusp at the cable impedance.. there, it'll be the transit time, 2 uSec.
John
with a 1000 foot cable, use a step function and a resistive load ranging from 4 to 150 ohms.
The settling time to 95% value will surprise you.
Also, the cusp at the cable impedance.. there, it'll be the transit time, 2 uSec.
John
I can hear the time smear already 😉
Even cheap pc supplies now have pfc correction.
Sent from my LG-H811 using Tapatalk
Even cheap pc supplies now have pfc correction.
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No it really won't which is why I went to twinax with Zobel terminations. They over ran the test batch so I have 2,000-4,000 feet extra, will know for sure after they finish pulling cable.
Right now working on heterodyne filters for the switching audio power amplifiers.
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No it won't what?
The only thing a zobel will do is damp out reflections as the speaker unloads at HF. While the speaker is pulling power in it's low impedance range, the zobel does little.
You have to resist trying to satisfy the TDR with a zobel at the far end of the cable. That has little bearing to the settling time of a 4 ohm load on a high z cable. It will however, protect the amp from oscillation as the speaker unloads at higher frequencies below the unity gain point of the amp.
If you really want to learn what is happening, use a step function and vary a resistive load at the far end. As I said, you will find the settling time rather interesting. Or, you could wave your hands at the moon.
John
It seems so.
Add that heavy loaded transformers intended for working close to their magnetic saturation achieve very good voltage regulation.
Thanks. I meant if there is a problem with the audio equipment’s transformer.
George
No the settling time won't surprise me. If I get the chance I'll post the oscilloscope shots.
The cable is not a high z cable. It took a bit to get through to the cable folks why I wanted certain features.
I only wave my hands at the moon during festivities when there are naked women dancing.....
I again look forward to scope shots with no axis information, no conditions, no schematic, no verbage explaining what you did... 😉
It shouldn't be difficult to design a specific cable with specific impedance with specific shield, or specific twist pitch. If you don't specify, you get what you get.
As to specific impedance of twinax, the shield alters only the hf impedance magnetically, and lf impedance only by capacitance.
That's a great example of the misapplication of perfectly good hands..
John
That's the part I was missing. Serves me right for trying to do 3 things at once.🙂
Compare the dc voltage inthe rectified filtered output between the pure sine and the 3% thd sine with the same rms value. It shows why rms is not helpful for rectified loads.
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If you are really worried about the AC supply, power off a stack if LiPo cells, never charging the cell pack in use...
While I like the concept, the op amp outputs will be very susceptible to destruction if the opamp power rails fall below the secondary voltage. You'll forward bias all the tubs on the chip. The turn on sequence is very important.
I suspect a transient spike can do that, so a good suppressor on the primary would be important.
John
Opamps establish the balanced power ground. Not sure how you think they will ever see the 84 volts output.
Running for better than 5 years.
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