[hpsdr] Pandora and FAN Noise

[Lyle Johnson]

I had *terrible* fan noise in my unit after mounting the fan to Pandora. 
  Today I had the opportunity to buy a couple of other fans, mount them 
and listen to the fan noise and at the same time evaluate the heatsink 
temperature on the LPU and on the LTC2208 on Mercury.

The short version is that I found if I spaced the fan into the Pandora 
enclosure by means of an 8-32 nut between the wall of Pandora and the 
fan at each of the four fan mounting screw locations, the noise level 
was reduced dramatically.

I tried an ANTEC Tri-Cool 92 3-speed fan ($6.99 at Fry's).  It was OK in 
the middle switch position.

I also tried a Thermaltake "Smart Case Fan Blue LED" model A2017 ($14.99 
at Fry's).  I set this up with the variable speed control and found a 
setting that is very quiet when using the 8-32 nuts as spacers.  Without 
the spacers it, too, was very noisy.

I can now hear pileups on 20 meters using Mercury+Ozy+Atlas+LPU in 
Pandora with an old amplifier computer speaker and KISS Konsole 1.01. 
Before this, I had to listen to the fan...

73,

Lyle KK7P


 1244782890.0