Hantek DSO1152S - How to measure Maths output - Page 1
Forum section: electronics / testgear

author: WanaGo
author_rank: Regular Contributor
timestamp: July 13, 2014, 10:31:09 pm
content: Hello,After updating the firmware on my DSO1152S, I can now select CH2 on the MEAS button (before it was fixed on CH1 only).So now I can measure CH1 and CH2, however if I enable the maths function and do say CH1 - CH2, how exactly do you measure the result?In MEAS I still only have the option for CH1 and CH2, I get no MATH option.Any ideas?ThanksWanaGo

author: WanaGo
author_rank: Regular Contributor
timestamp: July 13, 2014, 10:55:17 pm
content: Got an AC-AC adaptor I am trying to measure. 240V AC to 12V AC. Trying to measure the secondary side.Sorry Im not the most experienced with scopes I have to admit.Trying to measure the AC waveform. Have CH1 on 1 lead and CH2 on the other lead. GND's are floating.MATHS function is set to CH1-CH2MEAS only has option to measure CH1 or CH2. Currently measuring CH1.Here is the output, attached pic_1_1.jpgStrange about the Freq and Voltage at the top right. Not sure what those are showing exactly. Hmm.. maybe they are the DMM actually, which is N/C.As I type this, if I connect the COM lead of the DMM to one of the leads on the AC-AC output, the two channels waveforms look more like Sine waves...Any ideas?Attached, pic_1_2.jpgThanks

author: tinhead
author_rank: Super Contributor
timestamp: July 13, 2014, 11:06:37 pm
content: Quote from: WanaGo on July 13, 2014, 10:55:17 pmyes, it is from DMM, this can be disabled (don't remember where ...)

author: tinhead
author_rank: Super Contributor
timestamp: July 13, 2014, 11:29:44 pm
content: Quote from: WanaGo on July 13, 2014, 10:55:17 pmwell, with floating gnd it will look like it does. DMM COM is connected via 10u to DMM IC COM and that via 680pF (2kV) to DSO GND which is, on your model, connected via some pf/nf (these huge blue caps) to channels GND. So yes, that enought to get the signal "properly" AC coupled. You should however watch the ratings here, your DSO is isolated but there are max values as well.

author: commongrounder
author_rank: Frequent Contributor
timestamp: July 13, 2014, 11:33:43 pm
content: Just to add to Tinhead's knowledgeable response: I have a DSO1122S, with the isolated inputs, like yours. If you are going to try and measure differentially, using the CH 1 and Ch 2 probes, you need to clip the two ground alligators together so the isolated inputs have a common ground reference. That should clean up your waveforms, and the waveforms will be out of phase with each other. You can then use the math "add" function and use the cursors to measure the result. Also, the point of an isolated input scope is to make it safer to measure ground/earth referenced voltages, since the common lead on the input channel is isolated (through caps as Tinhead has said) from the other channel and from the system ground of the scope. You could just use one channel's probe leads clipped across the secondary output and use the measurement functions to get your values.What version of the firmware are you using. I am not sure it is the latest, looking at your screen captures.

author: tinhead
author_rank: Super Contributor
timestamp: July 13, 2014, 11:39:59 pm
content: Quote from: commongrounder on July 13, 2014, 11:33:43 pmwhen talking aboutfirmware, he got massive problems aftr update to latest version (2.01.1_140408.0),https://www.eevblog.com/forum/testgear/hantek-dso1152s-wont-boot-after-firmware-update/msg478641/?topicseen#msg478641i wasn't able to use it as well on dev board when loaded via rcS (only manually started was working).What fw version is on your handheld and what hardware revision is that? (see sysinfo)

author: WanaGo
author_rank: Regular Contributor
timestamp: July 13, 2014, 11:44:35 pm
content: Thanks guysYes I tried clipping the 2 GND's together, made no difference at all to the waveform shown.But any idea how to get it to measure the MATH output? My colleague has a Hantek PC based scope, and he has the option for CH1, CH2 or MATH.First firmware I had was from 2012 which it shipped with, and it only had CH1.Upgraded as Tinhead said to the 2014 one, however all sorts of issues. Forced it to run the dso app via the serial UART, and yes, it looks different, there is a Hantek logo on the main scope waveform page etc. However I had to back it off to the 130129 firmware so I could get it to boot the scope normally and successfully. Something is wrong with the 2014 update. Quite a few more files in the 2014 update if you compare the files in the .up files....Anyway.Thanks for the responses. Any idea about the MEAS and the MATH though?ThanksWanaGo

author: commongrounder
author_rank: Frequent Contributor
timestamp: July 14, 2014, 12:01:28 am
content: Tinhead, My scope is using sw ver 2.01.1(140212.0). Hw ver 10020x555583e8 The screen has "Hantek" in upper left of screen.Boots up fine.

author: WanaGo
author_rank: Regular Contributor
timestamp: July 14, 2014, 12:10:26 am
content: my HW is 10010x555583e8SW now 2.01.1(130129.0)SW 2.01.1(140408.0) for DSO1152S is the one that caused me grief.

author: commongrounder
author_rank: Frequent Contributor
timestamp: July 14, 2014, 01:00:53 am
content: I guess I'm going to skip that version and wait for them to fix the bugs. Am I correct that the firmware is identical for all of the "S" type handhelds (tinhead)?

author: tinhead
author_rank: Super Contributor
timestamp: July 14, 2014, 06:24:17 pm
content: so far i know the firmware is only checking if the hw is 1002 or 1004, but not 1001. My initial thougth was "aha, that must be the problem with 2.01.1_(140408.0)_S firmware". But it seems that even if i set hw revision to 1002 (or even 1004) the affected firmare 2.01.1_(140408.0)_S is still having problems when started from rcS. Sure, simply EEPROM change might be not everything, but i haven't seens anything special in the firmware, so whatever it is, it didn't work as is should.There are no different firmware versions for all these 3 hw revisions of isolated handhelds, they all the same (models as well)