Are all oscilloscopes as noisy as Rigol oscilloscopes? - Page 1
Forum section: electronics / testgear

author: Rene
author_rank: Regular Contributor
timestamp: November 04, 2014, 06:45:09 pm
content: Hello,I recently purchased a Riglol oscilloscope (DS1104Z to be exact) and I am probably going to end up returning the unit. The primary reason for doing this is the fan noise. My home lab is in a pretty quiet room and the Rigol oscilloscope fan noise sticks out like blistering hemorrhoids.Before I bother going into all the trouble of returning this thing and begin searching for a replacement, I was curious if someone could tell me if other oscilloscopes are just as noisy as the Rigols ones and if that is the case, I should perhaps just keep the Rigol one.By the way, I went to my local electronic store and saw an Agilent oscilloscope and that thing was whisper quiet. What I don’t know is if it was whisper quiet because it was idling but once I start using it the fan will rev-up and be just as noisy.Thank you.

author: jancumps
author_rank: Unknown
timestamp: November 04, 2014, 07:14:00 pm
content: The DS1052E is certainly noisy too. There are mods published with alternative fans that can be fitted into that one.

author: diyaudio
author_rank: Frequent Contributor
timestamp: November 04, 2014, 07:16:20 pm
content: Quote from: Rene on November 04, 2014, 06:45:09 pmI have no idea how they could QA such a noisy instrument.

author: HighVoltage
author_rank: Super Contributor
timestamp: November 04, 2014, 07:22:37 pm
content: Be happy that you do not have a Lecroy WavejetThat sucker was so noisy, I returned after one day.On the other hand, I have a Rigol DSA815 and you can hear the fan, but it is not too noisy.May be they improved it for the SA.

author: coppice
author_rank: Super Contributor
timestamp: November 04, 2014, 07:28:37 pm
content: Quote from: Rene on November 04, 2014, 06:45:09 pmIt probably seemed whisper quiet because you were in a shop. Most things seem quiet in an environment like that. Get it home, to a genuinely quiet room, and it won't sound so good. I don't think I've ever encountered a piece of test equipment with a quiet fan. Noise isn't one of their priorities, as most labs are far from quiet.

author: rodcastler
author_rank: Regular Contributor
timestamp: November 04, 2014, 07:33:59 pm
content: Quote from: Rene on November 04, 2014, 06:45:09 pmYou could change the fan to a larger, quieter version and add a series resistor to it. I did that to my Rigol the very same day I got it and I've been happy with it ever since. Way easier and quicker than returning the unit.Plenty of how-to's out there by the way.

author: Rene
author_rank: Regular Contributor
timestamp: November 04, 2014, 07:44:29 pm
content: Quote from: rodcastler on November 04, 2014, 07:33:59 pmI was thinking of doing that but that would mean removing the guaranty sticker and the idea of losing my 3 year guaranty stops me dead in my tracks. I know there are ways to remove the guaranty sticker in a non-destructible way so it can be reuse but I am not sure I have the kahunas to take that risk.

author: jancumps
author_rank: Unknown
timestamp: November 04, 2014, 08:17:19 pm
content: Quote from: Rene on November 04, 2014, 07:44:29 pm

author: dentaku
author_rank: Frequent Contributor
timestamp: November 04, 2014, 09:38:10 pm
content: Mike Harrison actually did a video on removing the Rigol warranty sticker without breaking it.It's also good that Rigol 1000 series scopes seem to have fans that use two pin connectors and not soldered directly.

author: HiTech
author_rank: Regular Contributor
timestamp: November 04, 2014, 09:49:33 pm
content: My LeCroy is on the noisy side I would say. I think a portion of most fan noise is the type of construction around it that tends to make it loud. My HP gear has fans that can be a bit on the loud side but not annoying when only one item is powered up. Turn them all on and the room sounds like a power tool running. High cfm fans are going to be louder than those that aren't moving volumes of air.

author: nctnico
author_rank: Super Contributor
timestamp: November 04, 2014, 10:00:43 pm
content: My Siglent SDS2024 is pretty quiet compared to the oscilloscopes I have used before.

author: Isaac000
author_rank: Contributor
timestamp: November 04, 2014, 10:02:58 pm
content: I've used a lot of different kind of scopes, old and new, analog & digital. Of the scopes I currently have on hand, an old LeCroy WavePro is what I would consider to be quite noisy and borderline unacceptable.At my last place, I also acquired a Rigol, not exactly your model, but similar. The first thing I noticed was the audible noise. Was it noisier than the LeCroy? Possibly not, but given the sheer size & age of the LeCroy, I kind of expect it to be a bit loud. But not for the Rigol. It was unacceptable, loud enough that I decided not to procure it for my own personal oscilloscope despite the extra low cost. I'd rather eBay for an old TDS754 or something similar before I spring for one of those new Rigol's. I spoke with the Rigol rep about that and he assured me the newer 2000 & 4000 series were significantly quieter, but I've not seen them myself.I have even used old Tektronix Type 547/545 era of scopes and I don't remember it being as annoying as the Rigol. (Again, that might be expectation for what is a near 50 year old scope that rolls on its own massive cart).Most of the recent HP/Agilent/Keysight , Tektronix, Yokogawa scopes I've tried are fairly quite and nowhere near the Rigol.

author: Alex Eisenhut
author_rank: Super Contributor
timestamp: November 04, 2014, 10:11:38 pm
content: Quote from: Isaac000 on November 04, 2014, 10:02:58 pmI find my 547 quite pleasant, especially as winter approaches, and the fan is very large so it doesn't spin too fast.It's about like a room fan.

author: HighVoltage
author_rank: Super Contributor
timestamp: November 04, 2014, 10:52:31 pm
content: I exchanged a lot of fans in older HP/Agilent powers supplies. If you use a low noise fan for replacement with temp control NTC, they get so quiet, you almost don't hear them anymore. I just was not ready to do this on a new LeCroy scope. This subject should not even come up anymore in these days, if the manufacturer would do it right from the beginning.

author: Rene
author_rank: Regular Contributor
timestamp: November 04, 2014, 10:55:26 pm
content: Quote from: Isaac000 on November 04, 2014, 10:02:58 pmThere is a guy on youtube that reviewed one fo the Rigol 4000 series oscilloscope and he states that the fan is pretty noisy.Also, at the beginning of the video you can tell that when he turns off the oscilloscope, the video noise drops significantly making it pretty clear that the unit is noisy.Who knows, personally, I doubt they are any quieter.

author: miguelvp
author_rank: Super Contributor
timestamp: November 04, 2014, 10:56:02 pm
content: My home office is next to the kitchen so running water bugs me more than a silly fanAnd for some reason it seems to always be running (the water that is) I think I want to start a new project to remotely shut down the water main from my desk

author: kwass
author_rank: Frequent Contributor
timestamp: November 04, 2014, 11:17:30 pm
content: I replaced the fan in my 1054z with this one:http://www.newegg.com/Product/Product.aspx?Item=N82E16835352002&nm_mc=TEMC-RMA-Approvel&cm_mmc=TEMC-RMA-Approvel-_-Content-_-text-_-(You'll need to modify the connector to a 2-pin one.)I didn't add a series resistor as the result was very quiet and quite easy to ignore in a home office environment. I realize that this fan has somewhat lower airflow than the stock fan , but I think that Rigol assumes that their scopes might be in harsh, hot environments with little space between equipment. I've run the 1054z for many ours of the past month with no issues at all.I always replace the fan(s) (and often add a series resistor) in all my test equipment and PC's and have never had an overheating problem. Of course all of these are used in a home environment kept at less than 70F (21C).

author: Wuerstchenhund
author_rank: Super Contributor
timestamp: November 05, 2014, 02:24:46 pm
content: Quote from: Rene on November 04, 2014, 06:45:09 pmI don't know the DS1104z but I've experienced the DS2000 and DS4000 scopes, and no, to me they are not noisy in comparison to what is else out there, but they certainly aren't the most quiet devices either.One thing to consider however is that an electronics lab is no quiet room. Test equipment is generally noisy, as cooling and a stable temperature are important. If you think that your DS1104z is noisy then you should have a look at the noise high end scopes emit. In my lab I have a LeCroy WavePro 7300A 3GHz scope, which has three large and some smaller fans which, when turned on, sound like a jet engine powering up (and once the aquisition system is initialized another fan kicks in). But realisticly there is no way to cool things thing silently, considering the heat the front end and aquisition system alone puts out, which has to go somewhere.Noise perception is a very difficult topic. Aside from noise volume, the frequency plays a big part in if a specific noise is experienced as uncomfortable or not. The mentioned LeCroy WavePro scope for example is quite loud, but since the noise it emits is of lower frequency I don't experience it as bad as say the high pitch whine from the small fans in one of my PSUs, which are of lower volume.QuoteAs already mentioned by others, the reason you think it's not noisy could very well be because of the high background noise floor in the shop environment. You may well find that it's as loud or even louder than your DS1104z if you would try it in your home lab.If for some reason you want silent you might have a look at USB scopes which usually come without fans. But most of them have so many other drawbacks that accepting the noise of your Rigol might be the better option.

author: Wuerstchenhund
author_rank: Super Contributor
timestamp: November 05, 2014, 02:27:13 pm
content: Quote from: HighVoltage on November 04, 2014, 10:52:31 pmOf course there's no justification why a low performance scope like a WaveJet must be noisy, but some more advanced kit simply needs a lot of airflow for proper cooling, which means there often isn't much room to lower noise levels.

author: nctnico
author_rank: Super Contributor
timestamp: November 05, 2014, 04:22:54 pm
content: Quote from: Wuerstchenhund on November 05, 2014, 02:24:46 pmPerhaps but to me it is not acceptable to have such equipment near me. If I have to do tests with noisy equipment I set those up in a different room. IMHO an oscilloscope for bench use should not make more noise than a quiet PC otherwise it gets irritating and making measurements becomes a nuisance.

author: free_electron
author_rank: Super Contributor
timestamp: November 05, 2014, 04:28:20 pm
content: Quote from: HighVoltage on November 04, 2014, 07:22:37 pmyou should try their 7ZI series. the moment it starts acquisition there's like 9 fans going form idle to full throttle. you might as well strap a hoover vacuum at full power to your head...

author: Lunasix
author_rank: Regular Contributor
timestamp: November 05, 2014, 05:08:57 pm
content: I recently bought (already used) a Tektronix MSO2024 and I find it's too noisy, even with the variable speed of the fan. So, I don't know if it's possible to reduce noise with another fan. And I keep my TDS2014 (no fan inside) for simple measurement.

author: jpb
author_rank: Super Contributor
timestamp: November 05, 2014, 05:27:56 pm
content: Quote from: HighVoltage on November 04, 2014, 07:22:37 pmThe Wavejet is very noisy, the one saving grace is it boots fast so you can leave it off a lot!I have thought of changing the fan but the innards are very densely packed so I'm a bit cautious of it overheating.

author: Rene
author_rank: Regular Contributor
timestamp: November 05, 2014, 05:55:13 pm
content: Quote from: Wuerstchenhund on November 05, 2014, 02:24:46 pmTo be fair, I don’t mind loud equipment as long as the loudness is justified. What I can’t get past of is completely unnecessary noise.Perhaps I am wrong about this but to me it looks like the fan noise on many of the oscilloscopes is primarily due to the design team not considering noise to be an issue. If limiting fan noise was a factor in the design I am pretty sure they could easily change the design so that it practically required no fan at all.... atdleast on the low end scopes.

author: nctnico
author_rank: Super Contributor
timestamp: November 05, 2014, 06:15:15 pm
content: I agree. These low end oscilloscopes consume a few Watts max so with some proper air ducting through the housing it should be able to get by with natural convection. Also adding an NTC and a small SOT-23 mosfet would be nice to create a temperature controlled fan. Perhaps it's just a fashionable thing to add a fan to equipment. A more extreme example: I have a bunch of switching HP power supplies which used to have very loud fans. I modified all of them to temperature controlled fans and guess what: the fans never run at full speed even though the full-speed temperature is set to 45 degrees (measured on the heatsink).

author: eurofox
author_rank: Unknown
timestamp: November 05, 2014, 06:56:56 pm
content: Pffff you complain about this little noise when I switch on my microwave frequency/power meter is like a 747 that is taking offand it is new, seems to be normal

author: XFDDesign
author_rank: Frequent Contributor
timestamp: November 05, 2014, 07:23:21 pm
content: My TDS5032B sounds like I'm running my Vacuum cleaner is running.There also needs to be a very important question asked of everyone who is replacing a fan - how equal is the one you're replacing to the replacement? Someone linked this fan from new egg (http://www.newegg.com/Product/Product.aspx?Item=N82E16835352002&nm_mc=TEMC-RMA-Approvel&cm_mmc=TEMC-RMA-Approvel-_-Content-_-text-_-) and "ooh" it's quiet. Yes, well it also moves almost no air (4.64 Cu. Ft/min). Well you might be replacing it with something like this:http://tinyurl.com/pyq2tngYes, the original fan is noisy, but often it's due to having a necessary airflow requirement. Going from 17 CFM to 5CFM might have a lot of very nasty negative consequences on the thermals of the semiconductors. Recall in Dave's TDS3000 series teardown how the converters were running incredibly hot. Now reduce the airflow rate by 1/3 and see how well they perform and how long the instrument lasts.This isn't to say "never replace," as some fans are just cheap spit and can be replaced with a superior product. I am saying,just be mindful and don't replace things without thinking.

author: Lunasix
author_rank: Regular Contributor
timestamp: November 05, 2014, 09:56:06 pm
content: Yes, replacing a fan in a computer is not a big risk, and it's easy to verify temperature. But in a scope, smaller and with shielding, it's not obvious to prevent overheating and associated failures. And cost is not the same as for a desktop computer...In my scope, which already has a fan with variable speed (and I can hear speed variations), I think there's is no hope.Shame on the designers

author: David Hess
author_rank: Super Contributor
timestamp: November 06, 2014, 02:04:53 am
content: Quote from: Alex Eisenhut on November 04, 2014, 10:11:38 pmAnd about like a convective space heater although a 545 works even better for that.Most of my old analog oscilloscopes and DSOs are quiet enough to get left on if I am not paying enough attention.With small fans I would be concerned about operating lifetime.

author: TonyStewart
author_rank: Contributor
timestamp: November 06, 2014, 05:16:43 am
content: For a thousand dollar scope, one would hope they could use a decent fan. But a few dollars saved is their earnings.Keep the scope & plea for a replacement with a hydraulic bearing.Since they have no acoustic spec., they dont have to. Buyer beware.If you like everything else , change the fan and ask for permision to replace with this fan without trying be sly , yet keep the warranty. This is good user feedback mechanism.If they do not accept , ask for a refund and see what happens.http://www.silentiumpc.com/zephyr-60/?lang=enDont use a cheap fan that sounds quiet. Quality control is critical... even Nidec can be poor and Hall sensor misalignment, can cause some positions to be a dead spot on start.

author: Rene
author_rank: Regular Contributor
timestamp: November 06, 2014, 05:33:30 am
content: By the way, attached is a picture of the oscilloscope fan bay for the Rigol 1000 series. You can see that they placed the USB / Lan connectors right in front of the fan..... Seriously??? Is that supposed to help keep the system cool? No wonder they have to beef up the fan.

author: Sembiance
author_rank: Newbie
timestamp: June 13, 2017, 03:05:27 pm
content: Was looking for my first scope to be silent and found this thread on Google.Since the last reply, Rohde & Schwarz have come out with two silent scopes.The first is the HMO1002 serieshttps://www.rohde-schwarz.com/us/product/hmo1002-productstartpage_63493-61541.htmlIt has NO FAN and is totally silent.The second is the HMO1202 serieshttps://www.rohde-schwarz.com/us/product/hmo1202-productstartpage_63493-142720.htmlThis one has a fan, but it is DEAD SILENT. The EEVblog guy tore one down and was astonished at how silent:https://www.youtube.com/watch?v=q_FBwu2K7j0&feature=youtu.be&t=4m27sAnyways, since this thread is easy to find on Google for others looking for quiet scopes, I thought I'd reply with some useful new info

author: jjoonathan
author_rank: Frequent Contributor
timestamp: June 13, 2017, 04:01:56 pm
content: Quote from: XFDDesign on November 05, 2014, 07:23:21 pmYes, yes, yes! Also, caveat emptor. I was unable to achieve "equivalent cooling" on my DS4000 with a noctua fan despite the fact that someone else says they did. There's no substitute for measurement.

author: Fungus
author_rank: Super Contributor
timestamp: June 13, 2017, 04:10:02 pm
content: I've just ordered a fan for mine. I compared a couple of suggested fans here:https://www.eevblog.com/forum/testgear/rigol-ds1054z-ds1000z-fan-noise/msg1228358/#msg1228358The Gelid Silent 5 seems to be the closest in spec so that's what I ordered. I hasn't arrived yet though so I can't tell you first hand how much difference it makes. Other people seem happy though.

author: Osirison
author_rank: Contributor
timestamp: June 13, 2017, 04:36:04 pm
content: Quote from: Sembiance on June 13, 2017, 03:05:27 pmI do own a R&S HMO1202 as well and never heard the fan!

author: klaff
author_rank: Regular Contributor
timestamp: June 13, 2017, 07:26:08 pm
content: My HP 1725A has no fan at all. That was a nice feature. My new Siglent 1202X-E isn't silent but I don't find it objectionable.