[Elecraft] Samelex Power Supplies with a K3

[WILLIS COOKE]

I have a JetStream JTPS-35 switcher.  It has a humongous heat sink inside the box and has a fan that makes some noise when the transceiver is turned on.  However, I can't hear it when my Dentron Clipperton L is turned on.  The Dentron has an aftermarket Radio Shack fan.  The original fan was replaced before 1990 when I bought the amp second hand.  It seems that a big enough heatsink for the switching transistors might be counterproductive to the light weight.

I did reduce the fan noise quite a bit by tying the wires that were touching the fan blades to the heat sink with a twistie from a cord that I got with something.
 Willis 'Cookie' Cooke 
K5EWJ 




________________________________
From: Steve Ellington <n4lq at carolina.rr.com>
To: Paul Christensen <w9ac at arrl.net>; elecraft at mailman.qth.net
Sent: Sun, May 23, 2010 9:08:25 AM
Subject: Re: [Elecraft] Samelex Power Supplies with a K3

Paul....It makes me wonder if they couldn't just put a decent heat sink on 
those switchers and virtually eliminate the fan or at least make it very 
rare to ever turn on. I realize they want to keep them small and lightweight 
and I guess fans are cheap and light but I sure do hate the racket they 
make!

Steve
N4LQ
----- Original Message ----- 
From: "Paul Christensen" <w9ac at arrl.net>