Eric, I also recently received some enclosures... this is my two cents, YMMV, etc:
If the fan is installed such that it blows in onto the USRP, it will receive the direct benefit of the airflow. However, the fan makes a lot of noise in this configuration because the blades are right next to the perforated enclosure wall. Turning the fan around so that it exhausts air from the enclosure makes it quieter, but the airflow pattern has major components that enter the enclosure on the fan side and get blown right back out, providing much less cooling airflow over the USRP itself. The solution I decided on was to mount the fan in the exhaust mode and tape over the holes on the fan side of the enclosure (other than the holes covered by the fan, of course!) This arrangement produces maximum laminar airflow over the entire USRP assembly and minimizes noise. I find that clear packing tape works very well; it's just the right height, and it makes for a very clean installation if you put it on the inside of the case. If you really want to be a perfectionist, don't forget the holes between the fan and the front of the enclosure. :-) The only downside to taping the holes is that in case of fan failure, you have significantly restricted the opportunity for natural convection or external forced air entry. I assumed that, if the fan is a design necessity due to heat load, losing the fan would be a problem regardless of the number of air holes and would need to be addressed anyway. Good luck, Mike -----Original Message----- From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] On Behalf Of Eric A. Cottrell Sent: Monday, February 12, 2007 10:56 PM To: gnuradio mailing list Subject: [Discuss-gnuradio] USRP 4 Questions Hello, I managed to blow the smd fuse on my USRP. It seems to be a 1 Amp 603 fuse. Is there a certain one I need to buy? I would like to order one from Mouser. I got the enclosure recently. Where do I plug the fan in? Should the fan exhaust the air from the enclosure? 73 Eric. _______________________________________________ Discuss-gnuradio mailing list [email protected] http://lists.gnu.org/mailman/listinfo/discuss-gnuradio _______________________________________________ Discuss-gnuradio mailing list [email protected] http://lists.gnu.org/mailman/listinfo/discuss-gnuradio
