Oscilloscope & AWG connection problem - Page 1
Forum section: electronics / beginners

author: dalpets
author_rank: Contributor
timestamp: March 10, 2024, 02:11:15 am
content: As a total beginner I have been trying to get the same results shown in the below Youtube video.My equipment is Siglent oscilloscope SDS 1102CML (100MHz, 1 GSa/s) & Siglent AWG SDG 1020 (20Mhz, 125 MSa/s).The video is entitled “An introduction, oscilloscopes and function generators by Controls and Instrumentation Lab” @Using the connections shown in the video @ 9:15-11.40 & 11.43-15.30 I get NO waveform response from the oscilloscope corresponding to numerous attempts to configure the connected AWG.It seems that that the oscilloscope does not see the AWG at all.What might I be doing wrong here?Thanks

author: tooki
author_rank: Super Contributor
timestamp: March 10, 2024, 05:42:49 pm
content: There are two major starting points here: Is the scope working? And is the AWG outputting anything? It’ll be harder to diagnose the second if the first isn’t proven.For the first question: Can you see a signal using your scope’s probe compensation lug?If so: is the AWG’s output actually turned on? Is it a frequency your scope can see? How are you triggering the scope? Etc.

author: dalpets
author_rank: Contributor
timestamp: March 10, 2024, 06:51:33 pm
content: I get a square waveform with the compensation lug.The generator setting are as follows;channel 1square waveformfrequency 257hzamplitude 7.00Vppphase 0.0 degreesoffset -8.0mVdcduty 50.0%The oscilloscope;channel 1probe 10xtrigger edgemode autoch1 5.00mAM 5.0msCH1 edge 3.00mADC couplingVolts/Div Finef=400KHzMpos:600.0ysThe remaining issues that I have are;oscilloscope only displays a jagged sine waveform whereas the generator is set to square wave.generator displays one frequency value but oscilloscope displays a completely different value.generator frequency changes are not reflected in oscilloscope waveforms. frequency changes can only be made with oscilloscope dial.Thanks for any further help.

author: donlisms
author_rank: Frequent Contributor
timestamp: March 11, 2024, 04:01:40 am
content: Do you see A/C voltage on your DMM at the output of the AWG?Have you tried the Auto button in the scope?---I'm a little unsure what you mean when you write "5.0mA" and "3.0mA" for the scope settings. Oscilloscopes don't generally have much interest in current. I wondered if you meant "mV", in which case measuring 7 volts with that setting is going to be a little disappointing.I would suggest this: AWG 0.5volts or less, with a simple sine wave. No fancy settings; just defaults. Hit "Auto" on the scope, no fancy triggering, and you should be able to get a view of the signal.Then start changing one parameter at a time to migrate toward your end goal. In other words, maybe you've got too many variables spinning, and it only takes x one bad one to mess you up.

author: radiolistener
author_rank: Super Contributor
timestamp: March 11, 2024, 04:30:05 am
content: Check that you connected oscilloscope ground clip to AWG ground terminal and oscilloscope probe to AWG signal output terminal. If you reverse it, the AWG output will be shortened with ground from oscilloscope through mains.

author: tautech
author_rank: Super Contributor
timestamp: March 12, 2024, 02:22:19 am
content: Quote from: dalpets on March 10, 2024, 06:51:33 pmChange channel input setting from A to V.

author: Aldo22
author_rank: Super Contributor
timestamp: March 12, 2024, 09:07:21 am
content: When I wonder why I can't see anything, I usually forgot to turn on the channel on the AWG. This is particularly often the case with the second channel.I know that sounds stupid, but some mistakes are just stupid.

author: dalpets
author_rank: Contributor
timestamp: March 14, 2024, 11:50:24 am
content: Quote from: donlisms on March 11, 2024, 04:01:40 amYou nailed it on the head. the auto button fixed the problem. Thanks.I have another problem that I can't find a solution to. In the attachment here at the bottom left of the Oscilloscope display it shows Ch1 as 1.00V. This is not from my machine but captured from an online website review for the Siglent 1102CML that I am using.I want Ch1 to read 5.00v but my machine refuses to show anything other than an Ma(?) reading. I should instead have 1, 2 or 5v options.I have used both the measure button & vertical sensitivity button (V & mV) for Ch1 but I cannot get it to read in volts. I also don't understand what the ma notation relates to.Any ideas? Thanks.P.S. I have since checked the Siglent firmware updates but the versions numbers don't make sense & their release notes are generic, not for each release, so I can't reliably tell if my problem was ever a bug.My firmware is 5.01.02.29 but Siglent don't even list any version 5 firmware & they say their first update was 6.01.01.18 (their latest 6.01.01.25 2/8/23)?

author: dalpets
author_rank: Contributor
timestamp: March 14, 2024, 12:35:13 pm
content: Quote from: Aldo22 on March 12, 2024, 09:07:21 amYep that's what I did, too. definitely a stupid mistake!

author: Aldo22
author_rank: Super Contributor
timestamp: March 14, 2024, 01:28:05 pm
content: Quote from: dalpets on March 14, 2024, 11:50:24 amRTFM?To Specify Amplitude UnitSelect the amplitude display unit for the current channel. The available units are V and A.When the unit is changed, the unit displayed in the channel label will change accordingly.1. Press CH1button on the front panel to enter the CH1 function menu.2. Press the Next Page softkey to enter the second page of the CH1 function menu.3. Press the Unit softkey to select the desired unit V or A. The default setup is V

author: dalpets
author_rank: Contributor
timestamp: March 14, 2024, 02:49:30 pm
content: Quote from: Aldo22 on March 14, 2024, 01:28:05 pmDoneThank You.

author: tautech
author_rank: Super Contributor
timestamp: March 14, 2024, 07:41:45 pm
content: Quote from: dalpets on March 14, 2024, 11:50:24 amPlease confirm the model you have.SDS1102CML or CML+ ?They use different firmware.Version： V6.01.01.25 is not compatable with old CML HW.Last version I have for the earlier CML is V100R005B01D02P32

author: dalpets
author_rank: Contributor
timestamp: March 18, 2024, 12:37:08 pm
content: Quote from: tautech on March 14, 2024, 07:41:45 pmMine is your first mentioned vanilla version-ie., just CML.Do you agree that they no longer support my version & that it is no longer on their website?If so that's most unhelpful- why keep one & not the other?

author: tautech
author_rank: Super Contributor
timestamp: March 18, 2024, 07:37:42 pm
content: Quote from: dalpets on March 18, 2024, 12:37:08 pmEarly CML were superseded by the CML+ version in mid 2016 offering a higher res display and LAN support....nearly 8 years ago.IIRC price remained the same and the earlier HW was discontinued.As I mentioned we do have the old FW for the early CML models so if you need any we can supply via email. PM me.