Re: PI controller time domain responce in PLL from AC responce
On Fri, Dec 20, 2024 at 06:18 AM, john23 wrote:
My system is a frequency locked loop, ...
I could swear you said it was a phase locked loop.
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I get the feeling you do not seem to know what you are doing.? Am I mistaken?
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Andy
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Re: PI controller time domain responce in PLL from AC responce
Good grief, John.
Unless your system is really (I mean REALLY) poorly behaved
(seriously non-linear frequency vs. control voltage with
discontinuities and reversals), a simple proportional control,
perhaps with a little damping will work perfectly. I can't
understand why you insist on making this whole thing so
complicated. P+I is overkill for almost all control situations
that I've encountered. If you really need to drive the long-term
frequency error to zero, you may need a little Integral control,
but that is a very rare need. (Again, just my experience.)
Do you have any hardware to just try some experiments? Is the
hardware so expensive that you are spending weeks and months (of
your own and others' time) trying to get a fictional simulation
that may (or likely won't, as near as I can tell from all the
chatter) give you a clue about what values to use? Grab your pll;
set up its VCO to operate near your center frequency; make sure
your reference frequency is stable; take the error output and
divide it down with a couple of resistors (or amplify it, if it's
too small - rarely needed!); feed that back into the control input
and see if the output frequency matches what you want. There's no
reason for it to be so difficult.
By the way, I don't think in any of these email threads you've
actually told us what your objective is. What is the REAL problem
you are trying to solve? You keep asking "how do I fasten these
two boards?" when your real question is "how do I build a house?"
Donald.
On 12/20/24 06:19, john23 via groups.io
wrote:
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Re: PI controller time domain responce in PLL from AC responce
UPDATE:
My system is a frequency locked loop, by the diagram bellow, I intend to make a plot of a frequency Vs error signal as shown below.
Given this plot how would it help me to know the controller parameters i should use when building the controller?
Thanks.
/g/electronics101/photo/296358/3868979?p=Created%2C%2C%2C20%2C2%2C0%2C0
/g/electronics101/photo/296358/3868978?p=Created%2C%2C%2C20%2C2%2C0%2C0
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Re: PI controller time domain responce in PLL from AC responce
Hello The controller needs to sweep over the area where the resonance is.
Its frequency range is 2MHz , what controller specs can I take from this requirement?
Also I was told that I need to plot error signal Vs frequency responce for designing the controller.
But my YIG has a drift so its not so stable.
Also error signal needs to go to some controller driver in order to have the frequency responce of the FLL.
What is the strategy for designing the controller of the FLL?
Thanks.
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There have been several comments on high voltage measurements and probes buried in various messages. While fixing my microwave, I needed to measure the high voltage output from the transformer. As many have mentioned, a regular DVM cannot be used at that high voltage. I have a 1000 to 1 high voltage oscilloscope probe, but it is designed for a 1MΩ load, not the 10MΩ of the DVM. Adding a 1.11MΩ resistor across the input to the DVM compensated for the input resistance. I double checked measuring the 120AC.? The transformer output was 2,380VAC . As usual do not do it if you really do not know what to do. ? It was a bad high voltage capacitor.? Surprisingly, the very detailed service manual had a surprising error:? It described testing the high voltage diode in forward and reverse with a regular DMM using the diode test mode. ? It will read open both ways since the forward diode drop is typically 8V because of the stacked diodes. Bertho ?
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Re: Speaking of Oscilloscopes
Any indirect link is nefarious. Trust me. They (Amazon) now knows
where I got that link, and who you (Sheldon) are, when you looked
at the product, what your (and now my) computer model, operating
system, browser and likely other info are. (Try for
more. In particular, try looking a the "More Info About Your"
button.)
So here is the unadulterated, direct link.?
The product is described as "FNIRSI 1013D Plus Oscilloscope -
Portable Handheld Tablet Oscilloscope with 100X High Voltage
Probe, 2 Channels 100Mhz Bandwidth 1GSa/s Sampling Rate 7" TFT LCD
Touch Screen" for anyone who might want to look for a different
vendor without Amazon watching your browsing history.
This is all getting VERY afar of electronics, so this is my
absolute last comment on this thread.
Donald.
On 12/17/24 12:20, SheldonD via
groups.io wrote:
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Been kicking around idea of getting a pc based o-scope to keep in my tool box. My first ever was one that connected to a SoundBlaster Pro sound card. Have had a few over the years (portable pc based).
Came across this apparent jewel at Amazon.
To my eye, looks like a winner.
Amazon Share-Link, nothing nefarious beyond screwing up your looked at history.
Thoughts?
SD
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Re: Speaking of Oscilloscopes
Note: Most scope FFTs really really, totally, really on steroids suck bilge water.
I'd go so far as to say "all affordable oscilloscopes FFTs really suck."
Suck to mean "Don't work very well, barely useful."
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For real. meaningfull, high speed FFT go with one of the higher end DATAQ units.
?
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Re: "that flagged nebulizer use as smoking"
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My older sister had severe asthma, really bad. Mine was bad when I was younger but puberty brought hormonal changes that reduced the asthma attacks from one every week or so to one a month then "I outgrew asthma." Not really of course but I went almost a year without a major attack.
?
Today I have a bad attack maybe every 3 to 5 years and get that fun tight chest feeling about once a year.
Some perfumes will drop me to my knees as I strangle.
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I am under doctors orders to take a puff before swimming and other water exercise.
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My older sister called Albuteral "speed light" because it can be an intense CNS stimulant for some people.. Sure beats epinephrine (adrinaline) seven ways to Sunday thought.
Here is the wiki entry....
Worth reading so you'll understand the pharmoknetics.
I really like to know how my meds work.
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Re: Speaking of Oscilloscopes
Hi SD,
>>?Came across this apparent jewel at Amazon.
>> To my eye, looks like a winner.
>> Amazon Share-Link, nothing nefarious beyond screwing up your looked at history.
>>
>>?https://a.co/d/10yH0lr
Dave Jones of EEVLOG did a review on that specific scope. ?He hated it. ? The interface was all screwy and he had real difficult time figuring out how to use it. ?I forget the exact details but he didn’t like
it.
I have the Owon portable scope (model #?HDS2202S).
?In hindsight I should have bought a slower bandwidth model (I don’t need the bandwidth). ? For the portable, I’m mostly using it for car diagnostics. ?The way you adjust frequencies and voltage on this unit is little bit confusing but it’s still usable.
?They are always trying to save money by putting on one or two less buttons. ?I like the portability but these little scopes are missing many of the advance features of desktop units (like FFT, math, etc).
?= ?= ?= ?= ?= ?= ?=?
Before you buy a scope, look at many video reviews. ?Some are sponsored and they will only say nice things. ?Those reviews are mostly useless. ?Try to watch those who are not sponsored and so they will tell you all the goods and bads. ? That portable scope
you chose out looks tempting (portable, big screen, dials, etc.) but I think you might hate it and it would be a waste of your money.
Jong?
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Been kicking around idea of getting a pc based o-scope to keep in my tool box. My first ever was one that connected to a SoundBlaster Pro sound card. Have had a few over the years (portable pc based).
Came across this apparent jewel at Amazon.
To my eye, looks like a winner.
Amazon Share-Link, nothing nefarious beyond screwing up your looked at history.
https://a.co/d/10yH0lr
Thoughts?
SD
--
Nuno T.
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Roy wrote: "All of the stamps that we've been getting for ages are the kind that you don't have to lick"
Roy, it was joke!
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Re: "that flagged nebulizer use as smoking"
And all this time I thought Albuterol was a steroid.
A WY LEO with a case of the "lookie loos" rolled up behind me while on side of the road during a drive in company pickup. Asked what I was doing, I explained. He asked if could look around in the pickup. Told him yes, but only already visible, don't open any compartments, and I have to remain plugged in for few more minutes.
He got REAL suspicious, asked why he can't open compartments. Told him I didn't want all my tools and test equipment left laying on ground while having breathing issue when you "suddenly" get called away on an emergency when inspection complete. LEO got serious and said because your truck has DOT numbers, I can do what I want.
I asked who would I report his "interference to emergency medical treatment" to at the barracks? Would that be his Captain? Lieutenant? After staring at me a few more seconds, he got in his car and drove away.
~SD
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Re: PI controller time domain responce in PLL from AC responce
Hello Andy ,This driver is being built to be connected to a PI Controller which needs to tune my YIG into the resonance of the resonator.The data about the YIG and the resonance dip properties shown in the phots below.given the Q factor of the resonance shown below and the properties of the FM coil which we are driving to tune the yig.What circuit properties you think I need to to have for my controller ?Thanks.sesitivity: 450 KHz/mA3dB bandwidth 2.2MHzresistance 2Ohminductance 1.5uH
/g/electronics101/photo/296358/3868513?p=Created%2C%2C%2C20%2C2%2C0%2C0
/g/electronics101/photo/296358/3868514?p=Created%2C%2C%2C20%2C2%2C0%2C0
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Re: Speaking of Oscilloscopes
I do similar stuff.
I use a good quality bench scope, and a separate, reliable, HV probe: MICSIG.
In my case, devices under test can be, and are, transported to the test bench,
where all safety precautions are readily available and in place.
118kW sounds far above anything I've ever come across. I suspect my setup would not be up for that...
I would be ok with the 800V in the test equipment.
(yes, I can see the comments from a lot of guys: "YOU'RE GOING TO BE FRIED ALIVE!")
I think I'm in a position, as well as Sheldon, by the looks of it, where we can say:
"we know what we are doing, and know the risks involved. We are professionals at it, not DIY's"?
I agree with your perspective. A discard able one sounds like a good idea.
If the calibration thingy doesn't worry you, then yes. I would by that model you pointed.
After sales service doesn't seem to matter, considering their life expectancy... :D
Nuno T.
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-----Original Message----- From: [email protected] [mailto: [email protected]] On Behalf Of SheldonD via groups.io Sent: 17 December 2024 18:03 To: [email protected]Subject: Re: [electronics101] Speaking of Oscilloscopes Intended purpose is to look at waveforms / triggers of IGBT and their drivers on a 118KW aux pwr supply fed by 800vdc. Cost is a factor, I can see losing an IGBT & Driver violently and taking out whatever may be connected. Waveforms to actual IGBT are max 30vdc, so can use HV probe to a point. It is not uncommon for flash to occur across isolated area and blow out what has been connected. I did look at reviews, saw calibration comments. Needing something... disposable that can still capture pwm down to fractions of a ms. ~SD -- Nuno T.
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On Tuesday 17 December 2024 02:25:07 pm Gooey via groups.io wrote: No, it don't! ?All they do is ask you to complete the product registration,
put a stamp on it and mail it back to them.
Then, they remove the stamp and expose it to the blue space lasers and
Gotcha!
All of the stamps that we've been getting for ages are the kind that you don't have to lick... -- Member of the toughest, meanest, deadliest, most unrelenting -- and ablest -- form of life in this section of space, ?a critter that can be killed but can't be tamed. ?--Robert A. Heinlein, "The Puppet Masters" - Information is more dangerous than cannon to a society ruled by lies. --James M Dakin
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On Tuesday 17 December 2024 07:15:59 am wn4isx via groups.io wrote: I just threw away a 1k (1024) magnetic core plane driven by TTL. It dated from 1968. The college of engineering was tossing it in 1976 and I thought it might be useful. Wired it to a KIM-2.? It worked by what a headache
The Chyron (TV charater generator) at the university medica center had 5 core planes, stacked, they were 2 feet by 2 feet and 3k each for a total of 9k.
The 8" floppy drive was so stupid if the system issued a command change from track 20 to track 21 it backed the haed all the way back to track zero then stepped forward 21 tracks. sounded like a supressed maching gun. We replaced it with a dumb PC [original 5 slot IBM PC] with a 5meg hard file and the production people were so happy they wanted to have it's babies.
Somewhere i have several 4" squares I cut from one of the magnetic planes.
Core plane worked amazing well given how primative it was.
I hope it's not coming back.
We had a demonstration of TI's magenetic bubble memory....that crashed everytime the engineer tried ti rurn the program.
Magnets belong in compasses and children's toys,not computer memory! There is some talk in one of the test equipment groups (I forget if it's HPAK or Tek) about replacing some of the currently battery backed memory (currently some kind of Dallas chip I think) with what they're calling a ferromagnetic chip, so there's something of the sort out there. I remember years ago when some of the surplus junk places would offer a core plane for sale. I never got one, but I think it'd be kinda neat to have one hanging on the wall in here. -- Member of the toughest, meanest, deadliest, most unrelenting -- and ablest -- form of life in this section of space, ?a critter that can be killed but can't be tamed. ?--Robert A. Heinlein, "The Puppet Masters" - Information is more dangerous than cannon to a society ruled by lies. --James M Dakin
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Re: 50/60 Hz sine wave distortion
On Monday 16 December 2024 02:18:56 pm wn4isx via groups.io wrote: OK this is as crude as it gets...
That's the basic capacitive dropper circuit that Big Clive bumps into in a great many places. Maybe I should have specified operating from a 12VDC source... -- Member of the toughest, meanest, deadliest, most unrelenting -- and ablest -- form of life in this section of space, ?a critter that can be killed but can't be tamed. ?--Robert A. Heinlein, "The Puppet Masters" - Information is more dangerous than cannon to a society ruled by lies. --James M Dakin
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On Monday 16 December 2024 02:07:07 pm wn4isx via groups.io wrote: Dumb as a rock is sounding better and better for cars and trucks. Yep! My project vehicle is a '78 D200, and the only electronics in it at all are the igniion module (yay! no more points to deal with) and the voltage regulator, which is _not_ built into the alternator. -- Member of the toughest, meanest, deadliest, most unrelenting -- and ablest -- form of life in this section of space, ?a critter that can be killed but can't be tamed. ?--Robert A. Heinlein, "The Puppet Masters" - Information is more dangerous than cannon to a society ruled by lies. --James M Dakin
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Re: WN4ISX made a mistake!!!!
How fast an oscilloscope must I have?
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I used a DSO rated at 200MHz.
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I used ~120V [118V RMS], peak voltage 168ish, a 0.5uf [0.503uF] poly capacitor, a 1 ohm resistor to give 1V per amp, the CT-1 current probe, the scope in one shot storage mode and a push button NO switch.
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I've pushed the switch about 50 times and I never get more then ~0.04V across the resistor. That equates to ~0.4A, steady state was ~0.03V/A.
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Is my scope too slow to catch the transient?
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Perhaps I can't press at peak voltage... but I'd expect that at least once in 50 would result in a peak voltage. I might could rig a NE555 to start on zero crossing and turn on a SCR at peak, but that's more stuff on the 120V AC Mains then I like.
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I'll think this over and try again tomorrow or Thursday, we have water exercise and I suspect the PT gal is going to add some new fun filled exercise and I might not be up to doing anything serious.
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I've learned to not mess with 120V when you are tired. Too easy to make mistakes.
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And some of those were designed with slide rules and log tables.
Now that's primative.
Although I still have, and can use, my slide rule and I have my log tables my father used when he studied engineering pre-WWII.
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Re: WN4ISX made a mistake!!!!
Do not think about the problem as 60 Hz. At peak voltage turn on in the USA, you will instantaneously see 150V or so charging the capacitor with very little current limiting. The spike will be narrow.? Will an LED survive? Bertho ?
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From: [email protected] <[email protected]> On Behalf Of wn4isx via groups.io
Sent: 17 December, 2024 18:25
To: [email protected]
Subject: Re: [electronics101] WN4ISX made a mistake!!!!? Hum. Never considered that, I don't doubt you but will the instanious current ever exceed the Xc? It feels like the maximum current can't exceed the Xc.....and yea feelings are important but engineering is about science and getting the math right backed up by real world experiments. I just spent 30 minutes working the math several ways and can't come up with a fast transient from 60Hz, time for real world experiment. Sooo I could add the resistor, or, one of the two dozen 30A zero crossing solid state relays I've been trying to come up with a reson not to send them to recycle, or.... I used a similar scheme with a #47 light bulb, AC mains in, capacitor, #47 bulb, neutral, for at least a decade from 1960 until 1970 as a pilot light for a radio. I'll accept the resistance and inductance of a #47 bulb is very different from a string of LEDs. This is something interesting to test, I have a Tektronix CT-1 current probe, bandwidth? 20kHz to 1GHz. My scope has specs claimed to be good to 200, it will display 144MHz 2M signal with no obvious distortion. 0.5uf, 60Hz has an Xc of? 5305ohms. I'll measure it two ways, one direct AC hot to capacitor line through CT-1, to nuetral, then AC to capacitor to 100 ohms wire through CT-1, to neutral and see the max current peak on the scope. And I'll use Teflon wire rated at 2kV for the pass through wire through the CT-1.??
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Bertho
Gooey