I did a step by step "how to" somewhere.
Low speed is where it's at. I just want to move a little air, not create a hurricane.
I think that's what happened to Dan.

I use 3 speed computer fans and run them at low speed powered by an ac adapter.
Otherwise I run them at 5 volts off a power rail on a cpu power supply, or off a 6 or 9 volt power supply (a wall wart or ac adapter, whatever you wanna cal them).
My favorite is to stack a pair of 3 speed fans, add grills to each side, and power them off of a big 12 volt ac adapter. It sits around like a fan brick and I can keep the speed real low.
I use one like that in a wine fridge that I use for drinks so that ice doesn't form on the back of the fridge. Works awesome.
It works just as good in a vino or cabinet humi or whatever.

I run mine 24/7. I have no idea why anyone would want a fan to cycle on and off in a controlled environment, or where that idea comes from, but it's completely unessessary and goes against every air conditioning principle ever created.

I'm just saying.