The Siglent SDG2042X Thread

[markone]

My DS2072 scope with a quieter medium quality Scythe fan emits 1/3 the generator's noise subjectively. The gen sounds more like the original 2072 noise level albeit with a bit less annoying lower pitch hum.

Is it a Scythe Mini Kaze 60mm ?

I tried one inside mine GW-Instek SDS2072E in place of its shamefull ADDA, it's a fair device but i found Sunon Maglev even better also @ lower price.

In my case a lower depth fan (15mm instead of 20mm) worked a lot better for the reasons explained in a previous post, but that's not the case for the 2042X, where the fan is well placed inside the case box.

I'm quite picky about noise but i find my 2042X not boring at all, it's hugely less noiser than my DS1074Z, dunno how is the original DS2072.

[Salas]

Yes its the Mini Kaze 60mm as advised in a video and it worked very well for noise reduction but your Sunon slimmer solution seems even better as you described. So with your alike experience you can get the picture when I say that my 2042X is three times more audible than the DS2072 with the Mini Kaze.

[uncle_bob]

PAAD16025SL 0.15A 12VDC. Visible in Dave's video. The question is does the gen need a really strong airflow in home lab use? Or is it just a cautionary measure.

Hi

Back in the "old days" an instrument was expected to survive some number of hours sitting in a fairly tight cardboard box and doing it's normal operations. It always looked a bit odd to see the boxes on a bench with the cables coming out of them.

Indeed this could have been specific to certain west coast US instrument outfits. I saw several of them doing it. It may be something that nobody does anymore with today's tightly packed gear.

Bob

[markone]

PAAD16025SL 0.15A 12VDC. Visible in Dave's video. The question is does the gen need a really strong airflow in home lab use? Or is it just a cautionary measure.

ok, just checked through 2042x's case holes, the few P/N letters that i can spot confirm this FAN model also for my generator.

If i put my hand nearby the fan exhaust i do not feel a strong airflow, i will define it as "normal" air flow and considering the PAAD16025SL static air pressure of 4mmH2O (from http://www.aavid.com/products/thermal-fans/paad16025sl-pf00) a device like the Sunon HA60251V4-999 with its mere 1mmH2O will be a steep weakening.

Anyway i'm hearing only airflow noise and no fan's motor/bearing vibrations.

[Salas]

PAAD16025SL 0.15A 12VDC. Visible in Dave's video. The question is does the gen need a really strong airflow in home lab use? Or is it just a cautionary measure.

Hi

Back in the "old days" an instrument was expected to survive some number of hours sitting in a fairly tight cardboard box and doing it's normal operations. It always looked a bit odd to see the boxes on a bench with the cables coming out of them.

Indeed this could have been specific to certain west coast US instrument outfits. I saw several of them doing it. It may be something that nobody does anymore with today's tightly packed gear.

Bob

Hi

This gen is roomy inside for unoccupied space and I didn't see any particularly suspect for high dissipation components in the tear down video, maybe it could survive without a fan at all in winter time and a moderate breeze could keep it safe all around the year with medium use but not comfortable about trusting my hunch, better we had some numbers about the CPU's sink temp max allowed for long term reliability at least.

[Salas]

PAAD16025SL 0.15A 12VDC. Visible in Dave's video. The question is does the gen need a really strong airflow in home lab use? Or is it just a cautionary measure.

ok, just checked through 2042x's case holes, the few P/N letters that i can spot confirm this FAN model also for my generator.

If i put my hand nearby the fan exhaust i do not feel a strong airflow, i will define it as "normal" air flow and considering the PAAD16025SL static air pressure of 4mmH2O (from http://www.aavid.com/products/thermal-fans/paad16025sl-pf00) a device like the Sunon HA60251V4-999 with its mere 1mmH2O will be a steep weakening.

Anyway i'm hearing only airflow noise and no fan's motor/bearing vibrations.

Although near in CFM there is a pressure spec difference indeed. Maybe measuring the temp on that exit after an hour with both channels working will be an indication of how far less we can go.

[markone]

Although near in CFM there is a pressure spec difference indeed. Maybe measuring the temp on that exit after an hour with both channels working will be an indication of how far less we can go.

I have about 21W / 34VA of inlet power @ 230V with both channels set to 10Mhz & 10Vpp sine wave, for what is worth the  exhaust air is at 29°C while room temp is 21°C, IMHO not a good indicator if it is taken as a unique factor. 

[Salas]

The fan in my unit started making a slight annoying buzzing noise, so I opened it up to see if I could manipulate the fan to get rid of the noise (which I was able to).

While I had it open I noticed it had the Siglent signature rust on the edges of some of the metalwork. It was only slight and am sure it won't be a problem but does show poor attention to detail.

Its not a bad quality fan but there could be less air cooling circulation noise in this generator (which mainly comes from the box working like a speaker cabinet)

I don't know if it is calculated for worse case scenario when installed in a rack as it is, but for home lab use maybe a Sunon fan (HA60251V4-999 looks good) with some 3V drop resistor inline could suffice for safe cooling and about half the final audibility. Maybe Siglent can advise us here about which is the max CPU sink's temperature for long term reliability?

Hi

I'd bet the fan was picked on the basis of "this is what we stock for the other 20 instruments". Purchasing guys love that approach. The stock room guys love it as well.

If the heatsink is below 50C, it's a good bet that all is well. If it''s above 70C things may be ok, but life of the device is not what it might be. If it's over 90C, you need more air. All based on the "most chips / most places  / most ratings / most likely" guess. 


Bob

You have a most reasonable approach. If we will not have an official answer about temps, keeping the CPU sink between 50C - 55C would be a good rule of thumb for the sticker braking noise haters among us. 

[Salas]

Although near in CFM there is a pressure spec difference indeed. Maybe measuring the temp on that exit after an hour with both channels working will be an indication of how far less we can go.

I have about 21W / 34VA of inlet power @ 230V with both channels set to 10Mhz & 10Vpp sine wave, for what is worth the  exhaust air is at 29°C while room temp is 21°C, IMHO not a good indicator if it is taken as a unique factor.

Hmm... 8C above room ambient. Say you will not do lab work in a non air conditioned room above 28C and we go to 36C airflow exit temp. They would normally design for no more than 45C in-box ambient. It takes to probe on the CPU sink when testing a lower air flow so to be thorough.

[Macman]

The warranty sticker can be removed in the same way as is done with the Rigol stickers. I unstuck one side and bent it over and taped a piece of label backing over it so it could be reattach if needed. If you decide to detach the sticker don't rush it, mine was stuck quite well and took about 20 minutes of gentle persuasion.
The fan noise in mine is now quite acceptable to me and is just the air flow noise. I took it apart to sort out a buzzing noise that the fan started making.

[markone]

Hmm... 8C above room ambient. Say you will not do lab work in a non air conditioned room above 28C and we go to 36C airflow exit temp. They would normally design for no more than 45C in-box ambient. It takes to probe on the CPU sink when testing a lower air flow so to be thorough.

This room can easily reach 35°C Tamb in summer time without air conditioning, as actually did last year.

Anyway i would be more concerned for PSU and output stages than CPU device, actually it sits well served nearby the fan.

My ridiculously noisy old glory DS1022CD's (first series with 50mm fan) PSU reached gorgeus temp in some points (first place the 3.3V line's LM317 heatsink, well over 75 °C) while the exit air temp was absolutely not worrying, just because the case thermal design was completely wrong and the fan was not gathering air from right places.

A brutal FAN mod (see picture) reduced dramatically both noise & temp to an extent hard to believe, of course out of warranty time.

Recently i swapped the first 80mm fan with a "dimmed" ARCTIC F8 with even better result, i can ear only a smooth air sound.     

[markone]

... but your Sunon slimmer solution seems even better as you described.

yes, but only in that peculiar situation (metal shielding very close to fan intake), otherwise deeper fan are always better.

[Salas]

Hmm... 8C above room ambient. Say you will not do lab work in a non air conditioned room above 28C and we go to 36C airflow exit temp. They would normally design for no more than 45C in-box ambient. It takes to probe on the CPU sink when testing a lower air flow so to be thorough.

This room can easily reach 35°C Tamb in summer time without air conditioning, as actually did last year.

Anyway i would be more concerned for PSU and output stages than CPU device, actually it sits well served nearby the fan.

My ridiculously noisy old glory DS1022CD's (first series with 50mm fan) PSU reached gorgeus temp in some points (first place the 3.3V line's LM317 heatsink, well over 75 °C) while the exit air temp was absolutely not worrying, just because the case thermal design was completely wrong and the fan was not gathering air from right places.

A brutal FAN mod (see picture) reduced dramatically both noise & temp to an extent hard to believe, of course out of warranty time.

Recently i swapped the first 80mm fan with a "dimmed" ARCTIC F8 with even better result, i can ear only a smooth air sound.     

Same Arctic fan that I have used in my Korad PSU. Although much better than stock for normal operational noise, that PSU has an idle RPM choppy pulse drive that makes it sound like a coffee grinder with suicidal tendencies when no more than 100mA current is drawn to a load so to rev it up a little. I had used a Gelid in my older DS1052E (100MHZ mod). That one was an unbearable screamer to me, had to do something about it... I basically have to change a fan every time I buy an instrument. This is becoming ridiculous. Only my Siglent PSU was nice out of the box. I wonder if all the manufacturers will ever grow up and understand that poor noise design is detrimental to a brand's quality ranking? Many times its not only the fan itself but its the positioning and the flow. Rohde & Schwarz did it right in their small scope. Better they follow them. If they even manage 50% worse than R&D they will be successful enough.

[markone]

Same Arctic fan that I have used in my Korad PSU. Although much better than stock for normal operational noise, that PSU has an idle RPM choppy pulse drive that makes it sound like a coffee grinder with suicidal tendencies when no more than 100mA current is drawn to a load so to rev it up a little. I had used a Gelid in my older DS1052E (100MHZ mod). That one was an unbearable screamer to me, had to do something about it... I basically have to change a fan every time I buy an instrument. This is becoming ridiculous. Only my Siglent PSU was nice out of the box. I wonder if all the manufacturers will ever grow up and understand that poor noise design is detrimental to a brand's quality ranking? Many times its not only the fan itself but its the positioning and the flow. Rohde & Schwarz did it right in their small scope. Better they follow them. If they even manage 50% worse than R&D they will be successful enough.

I agree with everything you say, my last instrument purchase, the SDS2072E, can only further confirm all this complaining with its piece of cr@p fan, pathetically placed in a questionable overall thermal design, that provides lot of boring noise for ridiculously small air flow in a very limited case section.

Adding this to the weirdest feeling knob encoders ever seen in a scope (come on GW), a lot worse than my ATTEN ADS1102CAL's ones, leads me to think that in this brand some design compartments are missing their targets, while other are working very good, creating the harsh contrast between good performances and so so build quality details here and there.

This Siglent generator seems a fair device, but i still have to see the rust inside

Next time someone put his hands inside, please consider to take some pictures to nasty details ...
PS :dunno what version of Korad PSU are you playing with, time ago i considered them but after some youtube watching they seemed to be quite a crapfest, am i wrong ?

[Salas]

Its the 3A version of the small single output one that Dave had burned and they revised it to good. Mine is Tenma branded. Crap for general criteria construction quality but fair at the dirt cheap price. They also have a very good intuitive digital user interface and satisfying read out accuracy. The internal loop's speed is no good for high current  pulse or sinewave draw. It will ripple high if you will connect for a power test a class A/B amp drawing a couple of amps at 1kHz I mean. Adept, small, and reliable for general tasks though.

[markone]

Its the 3A version of the small single output one that Dave had burned and they revised it to good. Mine is Tenma branded. Crap for general criteria construction quality but fair at the dirt cheap price. They also have a very good intuitive digital user interface and satisfying read out accuracy. The internal loop's speed is no good for high current  pulse or sinewave draw. It will ripple high if you will connect for a power test a class A/B amp drawing a couple of amps at 1kHz I mean. Adept, small, and reliable for general tasks though.

Many thanks for the clear explanation, what you describe is exactly what i was fearing to :-)

I cannot forget the ugly R2R DAC inside spotted on Dave's tear down video, it seems from the soviet era, that circuit solution casts doubt on all the rest, to say the least.

I am a little biased toward these things after the HDG2002B purchase's mistake (what a crap !) but i know quite well that at the end of these stories i usually go for a decent device and the initial expense (for the crap) becomes a total loss.

If you keep in account time and materials to clean up the worst and the fact that you never completely trust it,

[Salas]

Get an Aim-TTi lab PSU if you can push your budget

[markone]

Get an Aim-TTi lab PSU if you can push your budget

Aim-TTI PSUs are actually quite expensive,  i was thinking more to something like ISO-TECH IPS-3303D, 300E plus taxes.

[ac122]

"Seems that the frequency counter leaks a 10 MHz signal to it's input."

We did identify a cross-talk issue that is causing this leakage to the frequency counter port. The factory tells me they are working on the problem.

Thanks for your comments.

Any information about fix for this?, I would assume this is an hardware issue and thus will only be fixed on newer units?
From which serialnumbers will this be fixed?

Hi

Equally on the same topic:

Assuming it is a hardware fix (it's the ribbon cable from the back panel ... ) what happens with in warranty existing generators? Will they be updated / upgraded / fixed?

Yes, it is a bit early to start digging into this. Right now, it might not matter to most. To the few who might be about to cancel an order for one, it could matter quite a bit

Bob

I was in the process of ordering one in early January and saw this post / issue.
So I have been holding off and waiting for a response / fix.
It seems that this might require more than a software update and would like to hear about the solution.
Obviously my preference is not buying a device with the problem.

So I decided to raise the issue once more for an update.

[dougg]

After upgrading to 2.01.01.17R5 firmware the problem with the count input injecting (odd) multiples of 10 MHz seems unchanged. For the measurements below I simply treated the count BNC as an output and fed it into my Rigol DS2202 (time domain) and DSA815 (frequency domain). The SDG2042X was set to output a DC waveform with 0 Volts offset. So the count "input" is outputting a 10 MHz square wave with a hell of a lot of ringing, with a Vrms of 44.85 mV. I set the SA to Volts on the y axis (rather than the default dBm). The harmonics drop off above 350 Mhz.

[Salas]

Get an Aim-TTi lab PSU if you can push your budget

Aim-TTI PSUs are actually quite expensive,  i was thinking more to something like ISO-TECH IPS-3303D, 300E plus taxes.

Looks like a good choice for the money. Its a popular GW Instek theme. The same core motif can be found in the Siglent PSU series.

[markone]

Actually the new SPD3303C it's even cheaper, 239 plus taxes, but i did not found yet a tear down.
Let's say that regarding bench PSU i prefer old styled led seven segment readout than more fancy , but also dispersive, TFT panel.

[Salas]

The Iso-tech looks like having better binding posts as well as sticking to the GW Instek more faithfully for a more direct user interface having two dials and discrete memory buttons.

[mongo]

FYI, if any of you have had issues with usbtmc on these units I may have filed a bug report that should be enough for them to fix the issue.  It appears that they are not honoring the 64byte bulk transfer size limit of their usb gadget driver so you have to hit the stack multiple times.  We are "lucky" enough that the ethernet interface provides root level access with zero passwords and they have debugfs mounted.

That noted with this insanely bad security hole open, I would highly recommend never attaching this device to any network. 

That said I am fairly happy with the device and the format for the arb .bin files is pretty easy to work with.

[Cervisia]

if any of you have had issues with usbtmc on these units

Are you talking about the Linux driver?

It appears that they are not honoring the 64byte bulk transfer size limit

This is unlikely; USBTMC transfers happen on a different abstraction level than USB transfers.
Could you please share your bug report?