silent scopes?

[sukandar]

Hi all,
after decades of happily working with a Tektronix TDS210, I recently decided it was time to upgrade and bought a Rigol MSO1074, mainly because I needed more channels, both analog and digital, and it seemed good bang for the buck. In terms of functionality it does everything I had hoped for, so no regrets there.

However, what I didn't expect was how loud the fan noise of this scope would be.
Now, this may seem like a minor quibble, but I work in audio, so I'm quite sensitive about this issue.
Fact is that I find myself using the old Tek more often than makes sense.

Not sure if this is reason enough to replace my new shiny purchase, but in general I'm curious if all modern/more powerful scopes require a strong fan nowadays to keep them cool.
Are there still scopes without any fan?

On a side note my other quibble with the Rigol is, how sluggish some of the controls feel.
Is this the price you pay for going with a cheaper brand?

Thanks for any comments,
Sukandar

[DaJMasta]

There are some manufacturers that pay more attention to it, I'd say R&S is top in this category from what I've heard, but it's also not a difficult modification to make.  The fan is generally just attached to the case and fixed to the board with a standard connector, so while you have to crack open the scope, you don't really have to remove anything but the fan in most cases.

Since they use standard computer case fan sizes, you can find a lower sound level one with similar performance specs (flow volume is usually given, static pressure matters and people will insist it's extremely important but in my experience as long as the flow path isn't too obstructed, it's not a big issue to use an rated for less pressure), then swap it in.

I would verify what kind of fan is in there to match/exceed specs, then verify that the pinout of the connector is the same - I've run into a few test equipment fans that have two pins of three swapped from the normal PC configuration.


Also worth mentioning that physical obstruction of the airpath, especially with hard edges (heatsinks, fan grilles, etc.) will increase noise and are generally harder to work around.  Sometimes a small spacer to keep the grille at a distance is helpful for this, but it rarely makes a big difference, and you do have to make sure you still have clearance on the opposite side.

[Fungus]

You can get much quieter fans if you're prepared to open it up and swap it. There's EEVBLOG threads discussing them.

eg. https://www.eevblog.com/forum/testgear/rigol-ds1000z-fan-replacement-any-long-term-experiences/

[HighVoltage]

If you want a scope without fan noise, get one without a fan.
The only new scopes I know without a fan, are the small models from Rohde & Schwarz, which used to be HAMEG.

[sukandar]

thanks, I'll try the fan replacement