Siglent SDS1072CML problem - buggy or broken? - Page 1
Forum section: electronics / testgear

author: mos6502
author_rank: Frequent Contributor
timestamp: October 01, 2013, 11:26:39 am
content: Hey everyone,today I received my shiny new Siglent SDS1072CML. After unpacking, powering up and checking it out, I quickly realized there's something wrong:When I turn the horizontal knob clockwise, any setting below 250ns results in the waveform not being updated anymore. Or rather ... it only gets redrawn at maybe once every 20 seconds or so, plus it seems to be at a random horizontal position, i.e., the triggering doesn't work anymore. But it's NOT a triggering problem - the only thing I do is change the horizontal scale. If I turn the knob back to 250ns, it takes about 10 seconds for the waveform to reappear and then it gets drawn normally (several times per second), and the scope works normally, as long as I don't go below 250ns.It doesn't matter what channel I use.Also, if use the auto setup, and push the "rising edge" softbutton, the scope hangs completely (screen is frozen and no response to any buttons) and I have to power cycle it. The auto setup works as expected when I push the "pulse train" and "single period" buttons.My scope came with hardware rev. 11-62-3.3 and software rev. 5.01.02.13. I've updated to 5.01.02.22 - no change in behavior.There was also a weird thing that the acquire menu showed a lower sample rate, i.e. 125MS at 250ns and then 250ms at 100ns ... and then only 500MS at 5ns. There was only one channel active. I've rebooted the scope and now it's normal: 500MS at 250ns and 1GS at 50ns.Anyway, all this is very strange. Is this scope defective? Is there a way to do a factory reset?Shoulda gone with Rigol I guess ...

author: echen1024
author_rank: Super Contributor
timestamp: October 01, 2013, 04:59:14 pm
content: Try a self cal...

author: mos6502
author_rank: Frequent Contributor
timestamp: October 02, 2013, 04:22:13 am
content: Oh, I tried the self cal ... and just about everything else.It's probably difficult to know what's happening by the description alone, so I made a video:http://youtu.be/0T6uKQDX7s0

author: pickle9000
author_rank: Super Contributor
timestamp: October 02, 2013, 04:59:47 am
content: Are you going to try for warranty or take the back cover off?If you crack it open have a look at the keypad connection, it's in a location that could impact the bottom of the power supply. If that's the issue a little tape will fix it.Also try posting in the Siglent thread,https://www.eevblog.com/forum/testgear/siglent-technical-support-join-in-eevblog/msg293611/#msg293611it may help.

author: mos6502
author_rank: Frequent Contributor
timestamp: October 02, 2013, 05:31:23 am
content: I'm not going to mess around with it, because I can still send it back for a full refund. I was hoping it was a software issue or possibly even a case of PEBKAC, but apparently the chances for that are looking slim now.I'm also not too impressed with the screen or the slow speed of the UI, so I might have sent it back anyway. But this makes the decision much easier. This scope has some good features compared to other scopes in the class, like separate knobs for both channels. But no matter how low the price and how good the features, it's all moot when the hardware is unreliable. I think I'll just drop the cash on a Rigol DS2072 one or two months from now.

author: wbooth.clearscene
author_rank: Contributor
timestamp: October 07, 2013, 08:30:48 pm
content: Do you still have the scope, or have you sent it back yet? This does sound like a firmware issue rather than hardware. It's interesting to note however, that one speed faster @100ns there is a relay click when moving even faster.Do you know the version?My v5.01.02.13 (with hardware version 11-62-3.3) had not shown any issues like this.

author: mos6502
author_rank: Frequent Contributor
timestamp: October 08, 2013, 05:51:29 am
content: It's already on its way back to the seller. It did seem to me like a software issue too, at first glance, but as I wrote in the first post, I've upgraded to 5.01.02.22 from the original 5.01.02.13 and nothing changed. I would've opened it up and checked for shorts, loose solder blobs, etc. if it wasn't for that silly warranty seal (which simply does not belong on test equipment, IMHO).