[Elecraft] [K3] K3 fan noise, part XXLIV

[Joe Planisky]

Since the responses to my inquiry about K3 fan brands/models have  
virtually stopped, I thought I'd post the results.  There are indeed  
at least 2 different fans in use in K3s:

Elina HDF6015L-12LB-1 and UTEC AT6015L-12L2B-ND2 and ND5

The Elina fans are made by Inaba Denki Sangyo, a Japanese company.   
You can find specs for this fan at http://www.europeanthermodynamics.com/Fans&Blowers/elina%20fan_eng.pdf

The UTEC fans are made by United Thermal Engineering Corp. Their  
office is in San Jose, CA. but their factories are in Japan, Taiwan,  
and China. http://www.utecusa.com/products/pdffiles/pid_1-45-152_%28SPEC%29AT6015L-12L2B%20ND1%2812-22-08%29.pdf

According to the published specs, the UTEC fans have a slightly higher  
rated speed (3000 rpm vs 2800 rpm), more airflow (15.4 cfm vs 10.6  
cfm), higher static pressure (2.21mm vs 1.5mm),and higher noise (24.8  
dBA vs 21 dBA) than the Elina fans.  They also operate over a wider  
range of voltages than the Elina fans (6-13.8v vs 10.2-13.8v).  Both  
use ball bearings.  Based just on the specs, I would expect the UTEC  
fans to be slightly more powerful and slightly louder.

 From the responses I received, it looks like the Elina fans were used  
on earlier K3s with serial numbers < 900 or so.

I received responses from 13 people (including myself), covering 13  
K3s.  If the reporter used words or phrases like "quiet", "silent",  
"never hear them", I counted their response as "quiet".  If they used  
words or phrases like "loud", "annoying", "I can hear them", I counted  
their response as "loud"

UTEC Quiet   3
UTEC Loud:   4
Elina Quiet: 6
Elina Loud:  0

With such a small sample of self-reported anecdotes of a subjective  
perception, the results of this little survey are statistically  
virtually meaningless.  However, they do suggest a direction for  
further research in that no one reported loud Elina fans.

I may have a chance to do some side-by-side comparisons between my K3  
and an earlier SN K3 in a few weeks.  If that turns up anything  
interesting, I'll report it here.

Thanks to everyone who took the time and effort to respond to my  
request.

73
--
Joe KB8AP


On May 23, 2010, at 9:19 AM, Joe Planisky wrote:

> The topic of K3 fan noise seems to come up every now and then, and
> each time it does there's a chorus of people who say the fans in their
> K3 are absolutely silent, and an equal chorus of people who say the
> fans are clearly audible.
>
> ...

> However, I'm also wondering if Elecraft has changed brands or models
> of fans from time to time.  It's possible that some brands/models
> might be quieter than others.