Have a look here:
Dave made a nice video how not to blow up you precious toy ;-)
Really ?
Shite that's slow.
Let me do one for a 1102X, bet it's under 4 minutes....
I feel pitty for you that you are so desperately trying to promote your siglent stuff in every thread here.
Is business going that bad for you?
Honestly I don't see a problem with his post. Almost 20 minutes to cal the scope is crazy long. Even my old Tek does SPC in less than 5 minutes for 4 channels. I haven't timed it exactly but I know it's in the 3-4 minute range from just watching the clock waiting for it. That kind of info is useful to new or potential users - I sure would like to know that before purchasing - it would be an unhappy surprise to me. It doesn't kill the scope in my eyes by any means, but geez that's almost an hour before you can trust measurements.
Without knowing what the self calibration covers (does) it doesn't make sense to compare the time.
That kind of info is useful to new or potential users - I sure would like to know that before purchasing - it would be an unhappy surprise to me. It doesn't kill the scope in my eyes by any means, but geez that's almost an hour before you can trust measurements.
So? The Siglents and Teks need more than 45 minutes. That's not really much better, is it?
That kind of info is useful to new or potential users - I sure would like to know that before purchasing - it would be an unhappy surprise to me. It doesn't kill the scope in my eyes by any means, but geez that's almost an hour before you can trust measurements.
Hmm... How often do you guys typically run self-calibration?
My espresso machine needs to be descaled occasionally, and I couldn't care less how long that takes, as long as the coffee tastes good.
I have always considered scope self-cal to be in a similar class of operation: Do it once or twice a year, or maybe if you move the scope to a different environment. (Say outdoors -- but I have not had that need yet.) Are you using it much more often?
That kind of info is useful to new or potential users - I sure would like to know that before purchasing - it would be an unhappy surprise to me. It doesn't kill the scope in my eyes by any means, but geez that's almost an hour before you can trust measurements.
Hmm... How often do you guys typically run self-calibration?
Me? Almost never. Maybe after a firmware update or when winter/summer arrives.
I never imagined my scope as a multimeter, I know the voltage readings are only about 5% accurate even when perfectly calibrated (it says so in the manual!)
If you know that simple fact you can relax and use it for what it's
meant to be used for, ie. look at the wiggly lines and see if they're the right shape or not.
5% accuracy is enough to see if there's a problem in the circuit. Everything else is just volt-head obsessing.
That kind of info is useful to new or potential users - I sure would like to know that before purchasing - it would be an unhappy surprise to me. It doesn't kill the scope in my eyes by any means, but geez that's almost an hour before you can trust measurements.
Hmm... How often do you guys typically run self-calibration?
Maybe once every 2 years. Probably when I notice the DC offset at the mV/division ranges is a bit off.
I am recalibrating only after a firmware update. Recalibrating time is not important, since you need to let the scope to properly heat for at least 1/2 hour before recalibrating. Otherwise, repeated recalibration is pointless.
Thanks, all. That makes me feel better. So I will keep doing what I've been doing (or rather not doing) regarding self-calibration... And I will keep not caring at all how long it takes.
geez that's almost an hour before you can trust measurements.
So? The Siglents and Teks need more than 45 minutes. That's not really much better, is it?
Typo I guess, otherwise no idea where you got 45 mins from ?
Nope, just basic math.
If the 17-minute Rigol takes "almost an hour" to calibrate then the original poster must have done a 42 minute warmup.
With the same math the 4-minute Siglent takes over 45 minutes.
The Siglent is therefore 23% faster.
Not exactly a showstopping difference is it?
Typo I guess, otherwise no idea where you got 45 mins from ?
Warmup time plus a few minutes for the actual self-calibration, I assume.
No cause to get overly excited, tautech. Don't hurt your head there...
Running the self calibration daily is severe overkill. On some oscilloscopes (Agilent DSO7000 series for example) running the self calibration even voids the calibration performed by a calibration lab. Hooking the probes to the calibrator output and check if the signal is OK is even better because you'll also test the probes.
Running the self calibration daily is severe overkill.
Agreed.
On some oscilloscopes (Agilent DSO7000 series for example) running the self calibration even voids the calibration performed by a calibration lab.
How can that be ?
If the conditions that the Cal was performed in are replicated (ambient temp, warm up time) and the official traceable Cal has nulled the internal reference errors, why would a Self Cal void any official Cal ?
I don't get it.
Might there be a bug in the Agilent DSO7000 Self Cal ?
Is there a note from Agilent that explains this behaviour and why it is so ?
If the conditions that the Cal was performed in are replicated (ambient temp, warm up time) and the official traceable Cal has nulled the internal reference errors, why would a Self Cal void any official Cal ?
I don't get it.
One word: "Lawyers".
Pushing a "self cal" button doesn't
prove it's working properly.
Running the self calibration daily is severe overkill.
Agreed.
On some oscilloscopes (Agilent DSO7000 series for example) running the self calibration even voids the calibration performed by a calibration lab.
How can that be ?
If the conditions that the Cal was performed in are replicated (ambient temp, warm up time) and the official traceable Cal has nulled the internal reference errors, why would a Self Cal void any official Cal ?
I don't get it.
Might there be a bug in the Agilent DSO7000 Self Cal ?
Is there a note from Agilent that explains this behaviour and why it is so ?
Not really but the manual says a performance verification has to be performed after a self cal using equipment with traceable calibration to make sure the oscilloscope meets it's specifications.
Running the self calibration daily is severe overkill.
Agreed.
On some oscilloscopes (Agilent DSO7000 series for example) running the self calibration even voids the calibration performed by a calibration lab.
How can that be ?
If the conditions that the Cal was performed in are replicated (ambient temp, warm up time) and the official traceable Cal has nulled the internal reference errors, why would a Self Cal void any official Cal ?
I don't get it.
Might there be a bug in the Agilent DSO7000 Self Cal ?
Is there a note from Agilent that explains this behaviour and why it is so ?
Not really but the manual says a performance verification has to be performed after a self cal using equipment with traceable calibration to make sure the oscilloscope meets it's specifications.
Hmmm.
Weird, I would call that a bug.
Hmmm.
Weird, I would call that a bug.
Here we see why the DS1054Z "bug" list is so long - anything outside of somebody's personal expectations
must be a bug!
Hmmm.
Weird, I would call that a bug.
Here we see why the DS1054Z "bug" list is so long - anything outside of somebody's personal expectations must be a bug!
You need to do some more study why equipment have Self Cal capability and why there is a need to use it occasionally.
Measurements are affected by primarily temperature and the combination of runtime and ambient might not equate to the temp when equipment was calibrated and if this is the case that Cal will not be valid. Component drift from aging is another factor and why manufacturers recommend yearly calibration for traceable accuracy.The best we have between annual calibration for those that require it is a Self Cal feature to null these temp discrepancies to make measurement more accurate. If it doesn't one can only assume the Self Cal routines themselves are flawed.
Running the self calibration daily is severe overkill.
Agreed.
On some oscilloscopes (Agilent DSO7000 series for example) running the self calibration even voids the calibration performed by a calibration lab.
How can that be ?
If the conditions that the Cal was performed in are replicated (ambient temp, warm up time) and the official traceable Cal has nulled the internal reference errors, why would a Self Cal void any official Cal ?
I don't get it.
Might there be a bug in the Agilent DSO7000 Self Cal ?
Is there a note from Agilent that explains this behaviour and why it is so ?
Not really but the manual says a performance verification has to be performed after a self cal using equipment with traceable calibration to make sure the oscilloscope meets it's specifications.
Hmmm.
Weird, I would call that a bug.
On a scope with a US $25k list price for the basic configuration from a manufacturer with over half a century of experience with manufacturing oscilloscopes? I don't think so.
Since I don't use the scope too often, I think I am going to deploy an automated weekly or monthly self-cal.
The scope have Ethernet connectivity so self cal can be initialized and queried by my always-on server. Just power the scope with an Ethernet-enabled power strip (so I can bypass the clunking power button, leaving it always on, and switch the power to it in software)
I need to cook up software for this task, and set up a cron job on my server to run it periodically.
That kind of info is useful to new or potential users - I sure would like to know that before purchasing - it would be an unhappy surprise to me. It doesn't kill the scope in my eyes by any means, but geez that's almost an hour before you can trust measurements.
Hmm... How often do you guys typically run self-calibration?
My espresso machine needs to be descaled occasionally, and I couldn't care less how long that takes, as long as the coffee tastes good. I have always considered scope self-cal to be in a similar class of operation: Do it once or twice a year, or maybe if you move the scope to a different environment. (Say outdoors -- but I have not had that need yet.) Are you using it much more often?
That is true. I suppose my head is just spinning from the handheld debacle I'm dealing with. It won't hold its calibration for more than a minute.