Well, I did something impulsive - Page 1
Forum section: electronics / general

author: slburris
author_rank: Frequent Contributor
timestamp: October 06, 2010, 03:37:04 pm
content: Time will tell if I did something impulsive *and* stupid. :-)Having just gotten paid, I decided it was time to finally get a betterhandheld scope to replace an ancient Velleman HPS5. The HPS5samples at a whopping 500Khz, so it's only useful for the most basicof things.So I went out and ordered a Hantek DSO-1060, a 150Ms/secscope with a 60Mhz bandwidth. The folks over at RCgroups saidnice things about thefamousbrandsoutlet.com, so in spite of thename, I ordered from them. Excellent communication on their part,and the scope arrived last night, just as they said it would.http://www.hantek.com/english/produce_list.asp?unid=79I haven't had time to do much other than calibrate a scope probeand so some basic tests of the multimeter. Using the calibration signal,the trace looks a little noisy, but I'm not sure if that the calibration signalitself, the scope, or if this is what to expect with an 8-bit ADC. Certainlyit's head and shoulders above the old Velleman unit.Some reports of a related model, the DSO-8060 have said that it becomesmore voltage inaccurate with signals above 10Mhz.Lots of testing ahead of me.Scott

author: slburris
author_rank: Frequent Contributor
timestamp: October 08, 2010, 04:24:35 pm
content: I took it apart, at least until I got stuck.First, you have to remove the battery. It's a 7.4v 3.5Ah unit.Next, look at the ends. There are 4 roughly rectangular coversthat need to be pried off. You'll find 2 screws under each cover.After you take those out, 8 screws totals, you can remove therear cover.I tired to remove this PCB and failed. There is a screw underneaththe BNC panel and I couldn't find a way to get access to it. But I was ableto peek underneath. The backside of this PCB is packed with parts, butI couldn't get a good enough look at it. If I end up breaking my scope,then I'll make a bigger effort.There is also a second PCB which handles the LCD and switches underneaththis one.Looking at the PCB we can see, you'll see the usual ICs that have been scratchedoff. I think we're looking primarily at the multimeter section of the scope onthis side. Also the PCB looks well made, the multimeter section is notimpressive. There's little in the way of input protection. Yes, theyare fuses, but they are standard, not HRC. Note that the 10 amp currentshunt runs right past one of the fuse holders. Someone has thoughtfullyput some heat shrink on the shunt so it doesn't short out. I'd rather theshunt had been placed father away so this would be an issue.Would I use the multimeter to measure the mains? Probably not. But it shouldbe OK for measuring low voltage circuits. In any case, I think of the multimeteras a bonus, not as a required feature of this scope.So I put the scope back together, and it still powers on :-)Next up, I'll do some functional testing. PCB photo in next post.ScottTh

author: slburris
author_rank: Frequent Contributor
timestamp: October 08, 2010, 04:32:41 pm
content: Here's a photo of the PCB.Scott

author: Simon
author_rank: Unknown
timestamp: October 08, 2010, 05:18:58 pm
content: photo missing,you will get the noise, consider the amount of pixels the screen has, then consider that the 256 levels have to be interpolated to the vertical amount of pixels that actually shows the waveform, then think that any ADC is accurate to +/-1+ bits and you will see that you will be getting at least +/-1 pixel of "noise" needless to say any real noise

author: slburris
author_rank: Frequent Contributor
timestamp: October 10, 2010, 04:45:54 am
content: Well, my first attempt to test out the scope was a mess.Why? I thought I saw a problem where as the frequencyincreased, the amplitude of the displayed waveformwould change (someone in RCgroups reported this).Well, I thought I was doing a valid test with my trustyWaveTek 288 signal generator, but I double checked whatI was getting with my Tektronix 2236 scope, and sawthe same behavior on that scope too.So, I think my WaveTek isn't outputing a constant amplitudeas I increase the frequency. It's supposed to, so theremust be something wrong with it. So now I have tofix another piece of test equipment in order to testsome test equipment!I've got an HP 3336 generator somewhere. If I can get thatworking, and it behaves well, I'll use that for the test.Otherwise, it's off to fix the 288, then back to the test.Scott

author: NiHaoMike
author_rank: Super Contributor
timestamp: October 10, 2010, 05:16:40 am
content: How about just check the relative amplitudes?

author: Simon
author_rank: Unknown
timestamp: October 10, 2010, 08:28:21 am
content: yea, compare it to the scope you already have

author: slburris
author_rank: Frequent Contributor
timestamp: October 10, 2010, 01:23:16 pm
content: Quote from: Simon on October 10, 2010, 08:28:21 amAs far as I can tell by eyeballing it, the scopes show identical waveforms atvarious frequencies. I think I'll warm up the Rigol, then I can post some screencaptures comparing the Rigol to the Hantek.Scott

author: Mechatrommer
author_rank: Super Contributor
timestamp: October 10, 2010, 03:06:09 pm
content: i wish you can show me picture on ampere graphing, i never saw that, pls give me a chance at least once in my life plsss.

author: saturation
author_rank: Super Contributor
timestamp: October 10, 2010, 05:42:06 pm
content: Thanks for the review and tear down. All you need do is pass a high frequency square wave to the scope and see how much distortion it has, that can qualitatively say a lot. Then compare its basic Vdc and Vac accuracy, and that's it. Everything else is optional but those are key features.Even if you don't have a comparison against a know working scope, it would help. You can compare the Vdc and Vac against your high end DMMs.

author: slburris
author_rank: Frequent Contributor
timestamp: October 10, 2010, 09:03:13 pm
content: In the photos below, I put a 1Mhz square wave into both the Hantek and the Rigol scopeand set them both to measure Vpp. The Hantek seems to consistently read a littlelower than the Rigol.I didn't even have to read the manual for the Hantek, as they use essentially an identicaluser interface to the Rigol. Who *really* wrote the software for these scopes?The Hantek seems much more optimistic about its frequency counter than the Rigol, butif you ignore the last few digits, they are quite close.Next, I'll post some 5 and 20Mhz tests.Scott

author: slburris
author_rank: Frequent Contributor
timestamp: October 10, 2010, 09:14:52 pm
content: Here's the same test for 5 and 20 Mhz. I'm not sure if I believe my WaveTek 288 isputting out a decent square wave at 20Mhz. I looked at the waveform with myTektronix 2236, and it still looks mostly like a sine wave. Both the Tek and the Rigolare 100Mhz (well, the Rigol is modified). I'd expect rounding of a 20Mhz signal, butsomething that looks so much like a sine wave?So I pulled out the best analog scope in my collection, a Tektronix 2465 300Mhz.Indeed, the waveform still looks like a sine wave. My conclusion is that my signalgenerator isn't generating very good square waves at higher frequencies.With that caveat, here are the photos. Note that the Hantek seems to roll offon its Vpp measurement vs the Rigol at 20Mhz.Scott

author: Mechatrommer
author_rank: Super Contributor
timestamp: October 11, 2010, 03:50:42 am
content: so far i think the Hantek is good enough! any chance measuring Amperage? to see say amperage oscillation from mcu wakeup to sleep mode? how about battery life?

author: saturation
author_rank: Super Contributor
timestamp: October 11, 2010, 06:05:58 pm
content: These are great shots. The Wavetek is 20 MHz generator? so sq. waves at 20 MHz will put out harmonics above 180 MHz, it might be off spec.For a quick test, Wavetek can be expected to put out good sq waves at freq/9, or say ~ 10, to make it easy, reflecting the highest harmonic. That would be just ~ 2 MHz sq waves. At least its freq/5, at the 5th harmonic, or ~ 4 MHz.The Rigol shows a decent sq wave at 5 MHz from the Wavetek, and the Hantek is rolling off as expected as a 60 MHz scope, the ends of the wave represent about 45 MHz or so, it would be good to see where the Rigol alone begins to show roll off using sq. waves from the Wavetek. My guess you can output near 10 MHz sq waves from the Wavetek before a roll off is visible.The Hantek has good response!

author: slburris
author_rank: Frequent Contributor
timestamp: October 11, 2010, 10:49:41 pm
content: The Wavetek 288 is a 20Mhz generator. Internally it generates triangle waves.There are shaped into sine waves or sent to a discrete comparator which switcheson the top and bottom of the triangle to convert to square waves.I guess I would have expected a 20Mhz square wave to look more like a square waveon the 300Mhz scope, but maybe the output of the wavetek is having trouble passingthe higher harmonics?Scott

author: saturation
author_rank: Super Contributor
timestamp: October 12, 2010, 04:10:49 am
content: Try comparing the Hantek and hacked Rigol to a 10MHz sq wave from the Wavetek. I think you should see the Hantek really roll off on the corners and the same start to happen on the Rigol. You can manually sweep up from 10Mhz and see how the changes occur from there.Quote from: slburris on October 11, 2010, 10:49:41 pm

author: slburris
author_rank: Frequent Contributor
timestamp: October 14, 2010, 02:49:00 am
content: Here are the results for the Hantek and Rigol with a 10Mhz square wave.I discovered that the Hantek doesn't like FAT formatted USB sticks, sothose tiny 32MB sticks won't be useful with it. It likes FAT32 formattedones just fine. The Rigol doesn't seem to care.shafri: I will do a current test, I just haven't had time yet.Scott

author: slburris
author_rank: Frequent Contributor
timestamp: October 14, 2010, 02:53:52 am
content: Just for fun, I pulled a 50Mhz TTL crystal oscillator out of my stock,a Fox Electronics F110E series part.Attached are the Hantek and Rigol response to this output.Scott

author: saturation
author_rank: Super Contributor
timestamp: October 14, 2010, 02:49:43 pm
content: Excellent, that is a near textbook response. However, we can't tell if the limitation is due to the Wavetek or the Rigol, regardless, both are good with sine waves to 100MHz, since the Hantek is clearly rolling off while the Rigol still looks great.Quote from: slburris on October 14, 2010, 02:49:00 am

author: saturation
author_rank: Super Contributor
timestamp: October 14, 2010, 02:54:35 pm
content: Its certainly doing well for both, except the Rigol seems to have some minor distortion at the peaks. This probably is reflected on the sq wave tests, there is some overshoot at the edges. This could be however, be from the probes. Check the probe compensation, or switch probes to see if the Rigol waveform improves.Quote from: slburris on October 14, 2010, 02:53:52 am

author: Nounours18200
author_rank: Contributor
timestamp: September 04, 2011, 07:37:59 pm
content: Hi slburis,You have written :Quotedid you make your final opinion on this point ? I ask you this question because on my DSO8060 I also noticed a noisy signal when I measured a squred signal generated by the DSO8060 itself.Thanks for your reply ,Nounours

author: Nounours18200
author_rank: Contributor
timestamp: September 04, 2011, 07:41:15 pm
content: You have written :Quotedid you make your final opinion on this point ? I ask you this question because on my DSO8060 I also noticed a noisy signal when I measured a squred signal generated by the DSO8060 itself.Thanks for your reply ,Nounours

author: KTy
author_rank: Newbie
timestamp: May 20, 2013, 06:56:24 am
content: Any updates on 1060 accuracy / noise / distortion ?I also have 8060 (they share same hardware except signal generator) and I am facing some offset + interference issue, even after calibrationSee here:https://www.eevblog.com/forum/testgear/hantek-dso-8060-noisy-channels/Thanks,