[Elecraft] Quiet fans for K3

[Jim Brown]

Exactly right, Clay.  It is, indeed, a matter of compromise between cost 
and how many customers care about whatever the characteristic you're 
trying to optimize. At least 90% (and 100% of my serious operation) is 
wearing headphones, and the times I'm using the speaker I'm monitoring 
while in the shack doing something else. So I've NEVER been bothered by 
the fans in my K3/100.

I DO hear the fan in my KPA500 when I push the TX duty cycle, so I've 
guessing that a few bucks spent on making it quieter without 
compromising cooling would be appreciated by a much higher percentage of 
users.

73, Jim K9YC

On Wed,2/3/2016 1:51 PM, Clay Autery wrote:
> Well, there are laws of economics for manufacturers, too.  And they are
> at times more rigid than those in physics.  <grin>
>
> Yes, I've been doing thermal design for 25 years.  You give me a big
> enough pile of money, I'll deliver your target temp at target location,
> with </= max specified "noise".
>
> 73,
>
> ______________________
> Clay Autery
>
> On 2/3/2016 3:43 PM, Lynn W. Taylor, WB6UUT wrote:
>> So, what is noise?  It's energy.
>>
>> Some of it goes into the fan and moves air, some is from turbulence
>> off the blades, and some heats the bearing.
>>
>> There are quieter fans that still move lots of air.  They have
>> carefully shaped blades and all of the flashing is cleaned off so the
>> edges are smooth.  Extra steps that cost more.
>>
>> I've replaced a lot of computer fans.  If the computer sits next to
>> me, I get quiet ones.  If it's in a server closet, I use higher-speed,
>> noisy fans, preferably ones with a very high MTBF, because I won't be
>> there to hear the server get quiet.
>>
>> 73 -- Lynn
>>
>> On 2/3/2016 1:26 PM, Clay Autery wrote:
>>> You can BEND the laws of physics, but you can't break them.  Within the
>>> package size dictated, you can only move so much air in a given
>>> timeframe, "silently".
>> ______________________________________________________________
>>