I'm curious if there are any specs or info on the acoustic noise produced by the various 3000X and 4000X scopes?
I intend to buy a scope for use in a very quiet room. To become more familiar with the 3000X, I recently rented a DSO-X 3014A. So far, I love the scope's features, but it's terribly noisy! I temporarily stalled the fan by poking tweezers through the slot, and it turns out much of the noise is a terrible hissing/sizzling that sounds like a switching power supply is dying.
On Dave's eevblog forum, someone pointed me to a service note documenting this problem. I'll try to attach the file. Tomorrow I'll call the rental company to see if they can exchange it.
So I'm left with a really mixed opinion... I love the 3000X speed and performance, but this **** thing is terribly noisy. Even without the power supply problem, the fan is far too loud for an extremely quiet room. It's really a deal breaker for me.
Perhaps the 4000X has a quieter fan? Hopefully it's also free of audible switching power supply noise? I looked over the datasheet but didn't see any specs about acoustic noise. Is there any such info?
I suppose replacing the fan would void the warranty? I've done that on other equipment, like a cheap Rigol scope that's been on my desk, but at only $800 it's hardly the risk compared to voiding the warranty on a $10K+ piece of equipment.....
The acoustic noise in the scope may come also from the display PSU. You can try to follow the modification in the note issued by Agilent it self. That circuit showed in that note is also very noisy in high frequency spectre (EMI). You can get some more informations about those aspects from my thread https://community.keysight.com/message/14924#comment-14924
BTW, you do not void any warranty if you open the box and change that noisy fan with another low noise one. The scope enclosure is not sealed (as I experienced my self with my device).
Is just regrettable that Agilent have not yet addressed those issues in theirs devices....