[solved]Rigol MSO1104Z raster is really laggy - Page 1
Forum section: electronics / testgear

author: psysc0rpi0n
author_rank: Frequent Contributor
timestamp: September 05, 2018, 11:24:47 pm
content: Hello.I just want to understand if this behaviour is normal only on Rigol scopes or if this ir normal to every entry level scope.The behaviour I observe is that when I set a big time scale, for instance, 5 seconds or 10 seconds, the scope takes for ever to complete a 'rastering' operation (not sure if this is the correct wording). In fact it will take sec/div times number of divisions of the screen. The problem is not this, this is ok and understandable. What is not quite understandable, at least to me, is that when that raster 'entity' that we see sweeping the screen only becomes visible after the left half of the screen was swept. This means that I can't see anything while the raster thing doesn't reach the center division. Only after that I can see the raster sweeping the screen from the middle to the right. I can't see the raster from the beginning, on the left most side of the screen until the middle of the screen.Is this normal? I see videos of other scopes where this doesn't happens. In fact, when a big time scale is selected, the voltage trace like resets and disappears from the screen and starts showing up again on the right side of the screen and going left as time goes by!Example video at about 5:20:

author: Mechatrommer
author_rank: Super Contributor
timestamp: September 05, 2018, 11:36:09 pm
content: Is it normal? Yes it is, its been like that since E version. Reason? Unknown. We dont know whats going on in the fw how it acquire/display data. Workaround? Use running mode. on Time button, mode yt, xy, running. Choose running mode.

author: Fungus
author_rank: Super Contributor
timestamp: September 05, 2018, 11:47:14 pm
content: It's called "triggering".The trigger point is usually at the center of the screen. The data to the left of the trigger is the signal capturedbeforethe trigger point so until the trigger happens it doesn't know to draw that data.I imagine it happens on all oscilloscopes.Quote from: psysc0rpi0n on September 05, 2018, 11:24:47 pmThat's "rolling" mode, you have to select it separately.

author: psysc0rpi0n
author_rank: Frequent Contributor
timestamp: September 05, 2018, 11:56:32 pm
content: Quote from: Fungus on September 05, 2018, 11:47:14 pmYeah, I know about the triggering, but in other scopes I don't see this like "freezing" behaviour. Either the trace is simply not there as in the video I posted or the scope doesn't look like frozen. Mine does until the center of the screen, even after the trigger has rastered the screen completely at least once!Like, I was trying to reproduce the capacitor discharge/charge curve and set the scope to 10 sec. I tried to charge the cap like 3 times and I couldn't see anything on the screen, because by the time the screen got updated, the capacitor was already completely discharged meaning I saw completely no event!

author: Fungus
author_rank: Super Contributor
timestamp: September 06, 2018, 12:15:53 am
content: It's going to depend a lot on memory depth and triggering mode. If the 'scope is in 'auto' trigger mode then it will fire after a timeout period even if there's no trigger. This may start drawing from the left (I don't have the 'scope here to look at so I might be wrong there).The 'scope in the video is obviously in "rolling" mode - signal coming in from the right and the trace moving left. You select that mode in the Time Base setting.

author: technogeeky
author_rank: Frequent Contributor
timestamp: September 06, 2018, 12:55:52 am
content: Quote from: psysc0rpi0n on September 05, 2018, 11:56:32 pmPeople who use Rigol 1054z as daily drivers probably aren't going to have access to other (better) scopes, so they won't know to compare. I certainly don't.To work around this issue, just move the trigger all the way to the very left of the screen (sometimes I go 1 pixel left of the screen, just where the trigger arrow which usually points downward, points to the left).The main annoyance with this workaround is that you have to reset the trigger level and do it again for every change in the horizontal timebase; and since the velocity control isn't very good on this oscilloscope it's a pain in the butt.

author: Fungus
author_rank: Super Contributor
timestamp: September 06, 2018, 02:19:59 am
content: You can also set it up with non-auto trigger and press the "force" button when you want to start recording.

author: Mechatrommer
author_rank: Super Contributor
timestamp: September 06, 2018, 06:02:10 am
content: Quote from: psysc0rpi0n on September 05, 2018, 11:56:32 pmwhat you see in the video is the rolling mode. go change your dso setting now and see what happen.

author: psysc0rpi0n
author_rank: Frequent Contributor
timestamp: September 06, 2018, 08:32:05 am
content: So are you all guys saying the guy in the video said one thing and did another? Like he said he set the scope for 10 seconds and he even showed the scope rastering really, really slowly and then he selects the Rolling mode? My rolling mode locks the time setting at 200ms/division. Not sure I can see the curve at 200m/division but I'll try.Sent from my SM-G935F using Tapatalk

author: Mechatrommer
author_rank: Super Contributor
timestamp: September 06, 2018, 08:51:36 am
content: Quote from: psysc0rpi0n on September 06, 2018, 08:32:05 amhe already set his scope to roll mode before making the videoQuote from: psysc0rpi0n on September 06, 2018, 08:32:05 amthats the minimum time/div in roll mode. ds1000z can be set up to 50s/div. you should do, not try.

author: psysc0rpi0n
author_rank: Frequent Contributor
timestamp: September 06, 2018, 09:48:50 am
content: Ok, guys. I'm not cleared about this.Anyway, he wrote in that piece of paper 0.0001uF x 100000ohm = 10 seconds of time cosntant! How? I can't understand. That is 100ms in my calculator!

author: Mechatrommer
author_rank: Super Contributor
timestamp: September 06, 2018, 10:55:18 am
content: Quote from: psysc0rpi0n on September 06, 2018, 09:48:50 amthe first time i watch the video i thought his face like curt cobain style of rock n roll singer, now probably this time proved it... thats 100pF * 100KOhm, thats 10 us. listening closely at 2:25 he mentioned 100uF (100pF is unbelievably small), so lets do again... 100uF x 100Kohm = 10 seconds. maybe in his country the way one hundred is written is 0.0001

author: Fungus
author_rank: Super Contributor
timestamp: September 06, 2018, 11:06:16 am
content: Quote from: psysc0rpi0n on September 06, 2018, 08:32:05 amIt was in rolling mode the whole time. He even shows you it scrolling at 3:15.

author: Fungus
author_rank: Super Contributor
timestamp: September 06, 2018, 11:08:29 am
content: Quote from: psysc0rpi0n on September 06, 2018, 09:48:50 amJust goes to show: Don't believe everything you see on Youtube!

author: psysc0rpi0n
author_rank: Frequent Contributor
timestamp: September 06, 2018, 11:37:06 am
content: Quote from: Mechatrommer on September 06, 2018, 10:55:18 amI didn't thought about Kurt Cobain (my favourite singer and band ever) but for sure the guy didn't look that much into electronics, but that was judging the book by the cover. Anyway, I said 100ms but I also missed units. lol. I'm not drunk... Yet but I missed them too.So, the cap he used was probably 100uF and not 100nF. I think he meant to type 0.0001F that would be 100uF but he typed uF because he was thinking about the uF.

author: Fungus
author_rank: Super Contributor
timestamp: September 06, 2018, 11:43:50 am
content: Quote from: Fungus on September 06, 2018, 02:19:59 amI'm back in front of the 'scope and I tried that.When you press 'force' it makes the left half of the screen appear instantly and the trace continues from there.(the 'scope is always recording in the background so it has the data for the left side of the screen)If you want it to start from the left edge instead of the center (or anywhere else!) you can simply move the trigger point tho where it should start, as technogeeky suggested.Basically it all works correctly, as designed. There's no "lag".Maybe the title of the thread should be changed to add "(solved!)".

author: Mechatrommer
author_rank: Super Contributor
timestamp: September 06, 2018, 12:34:37 pm
content: Quote from: psysc0rpi0n on September 06, 2018, 11:37:06 ammaybe you are not drunk, but your avatar just look like Kurt Cobain too

author: psysc0rpi0n
author_rank: Frequent Contributor
timestamp: September 06, 2018, 01:14:07 pm
content: Quote from: Mechatrommer on September 06, 2018, 12:34:37 pmReally? My avatar is just a character of a game. Devil May Cry. But I like that I'm related to Kurt Cobain in some way!I'll change title to "solved".

author: David Hess
author_rank: Super Contributor
timestamp: September 06, 2018, 01:39:15 pm
content: This behavior just depends on the DSO; there is no requirement that pretrigger data not be shown continuously before the trigger in scan mode.On a Tektronix 2232 for instance in triggered single sweep mode, the pre-trigger data is rolled up to the trigger point continuously and then after a trigger, a scan is performed of the post-trigger data. It looks a little strange but only because most DSOs cannot do this. Offhand I do not know of any modern DSOs which support this but it only reflects a design decision not to bother.Note that it would be silly to do this with normal mode because the second sweep would roll pre-trigger data from the next sweep on the left while displaying the static post-trigger data from the previous sweep on the right. An untriggered mode would just roll or scan over the entire trace.

author: Mechatrommer
author_rank: Super Contributor
timestamp: September 06, 2018, 02:09:20 pm
content: Quote from: psysc0rpi0n on September 06, 2018, 01:14:07 pmanything long haired to shoulder and rock n roll like style is kurt cobain

author: psysc0rpi0n
author_rank: Frequent Contributor
timestamp: September 06, 2018, 02:10:02 pm
content: Quote from: Mechatrommer on September 06, 2018, 02:09:20 pmYou have a point there... HeheheSent from my SM-G935F using Tapatalk