Hi,
The following has been sort of haunting me for a while:
When I switch on my 2445B, the fan starts running at a low speed and is barely
audible. After a while, it increases its speed to what I consider its maximum.
It is quite audible by then. At the same time, I detect no air flow. Using a
piece of tissue as an airflow detector I can't "prove" there's any air flow,
apart from the fan's location at the back. Inside the 'scope, nothing is
impeding the air flow. This seems independent of ambient temperature, which
varies between 18C and 25C. The fact that I can't detect an airflow as such
does't give me much concern, since often it's just a little "moving air" that's
enough but i'd like to know if this is normal behaviour.
Can anyone of you confirm that it is normal for these 'scopes' (24x5y's) fans to
be running at or close to maximum speed under normal operating conditions?
FYI, I'd like to add that I'm sure it's not noisy bearings or anything like
that.
AAMOF, my TDS420 is even noisier, having a much larger fan as well.
My 465B isn't anywhere near as noisy, let alone my 7904 (which has no fan).
I'd appreciate to hear about anybody else's experiences.
Raymond
