Just a thought here...
There are many fans for computers which have a thermal control for the
fan speed built in. I suspect it's just a temperature-variable resistor
in series with the power lead. This could be a viable alternative for
cooling of almost any thing which needs it, and these things are cheap.
Look for phrases like "thermally controlled", "temperature controlled"
etc. With just a bit of searching, one can also find fans listed as
"silent". Many sellers of these fans list the sound level in DB, which
makes comparison easy, they almost always list RPM and CFM specs as
well. Also a variety of sizes from 40mm to 120mm and more. Try Cooler
Guys <http://www.coolerguys.com/>,
NewEgg <http://www.newegg.com/>,
Xoxide <http://www.xoxide.com/casefans.html?> just to name a few.
Hope this may help.
73, John W4CWZ
Alan Bloom wrote:
Yes, I expect a voltage regulator would work better than a resistor to
drop the voltage. Since the fan motor draws more current at startup
than when it is running, a contant-voltage source should give
more-reliable startup at a lower voltage.
But you probably still want to use a thermostat or some other method to
switch the fan to full voltage if things get too hot.
Al N1AL
On Tue, 2008-08-05 at 05:06, Kenneth A. Christiansen wrote:
I used a 5 volt regulator on my MFJ 4225 to slow down the fan. This allows
the fan to start reliably at any voltage. I have run mine and my K2-100 this
way for at least 5 years with no problem on SSB, CW and DIGITAL.
73
Ken W0CZ
Bill NZ0T Wrote
<As I'm not a very technical person I just used a couple of resistors in
<parallel to slow the fan down in my 4225. I can't remember the values this
<early in the morning but it seems to be working just fine. The supply does
<run a little warmer but not hot and the fan is no longer heard.
<
<Bill NZ0T
_______________________________________________
Elecraft mailing list
Post to: Elecraft@mailman.qth.net
You must be a subscriber to post to the list.
Subscriber Info (Addr. Change, sub, unsub etc.):
http://mailman.qth.net/mailman/listinfo/elecraft
Help: http://mailman.qth.net/subscribers.htm
Elecraft web page: http://www.elecraft.com
_______________________________________________
Elecraft mailing list
Post to: Elecraft@mailman.qth.net
You must be a subscriber to post to the list.
Subscriber Info (Addr. Change, sub, unsub etc.):
http://mailman.qth.net/mailman/listinfo/elecraft
Help: http://mailman.qth.net/subscribers.htm
Elecraft web page: http://www.elecraft.com
--
"The real proof that there is intelligent life in outer space is that they haven't
come here."
_______________________________________________
Elecraft mailing list
Post to: Elecraft@mailman.qth.net
You must be a subscriber to post to the list.
Subscriber Info (Addr. Change, sub, unsub etc.):
http://mailman.qth.net/mailman/listinfo/elecraft
Help: http://mailman.qth.net/subscribers.htm
Elecraft web page: http://www.elecraft.com
