[Elecraft] KPA1500 Power Supply Fan Noise

[Larry (K8UT)]

Eric,

My shack is a relatively quiet operating environment, but declaring 
something as quiet or noisy is always somewhat subjective. The fans in 
my PSU are pretty quiet, but nevertheless the KPA1500 PSU is 
remote-installed in a closet in my shack.

I am absolutely no "audio" guy, but years ago installed a free, cheap & 
dirty noise level meter app on my android phone called "Sound Meter." I 
use it to complain to restaurant managers that the blaring music in 
their establishments is too loud for casual conversation, demanding that 
it be turned down.

With the KPA1500 turned off and phone situated 3 feet from the power 
supply, the noise level in that closet is 28 DB. Turning on the 
amplifier raises the noise level by 12 DB to 40 DB - a 12 DB difference. 
Not much difference, and certainly not the "piercing power supply fan 
noise" you describe.

-larry (K8UT)

------ Original Message ------
From: "eric norris via Elecraft" <elecraft at mailman.qth.net>
To: "lists at w2irt.net" <lists at w2irt.net>; "lists at w2irt.net" 
<lists at w2irt.net>; "Elecraft Reflector" <elecraft at mailman.qth.net>
Sent: 2019-06-10 19:57:02
Subject: [Elecraft] KPA1500 Power Supply Fan Noise

>More broadly, has there been any progress on reducing the piercing power supply fan noise on the KPA1500 when only using it as a tuner or an antenna switch?  I complained about this a year ago, and I find it completely unacceptable.  No set of noise-reducing headphones that I have tried works well enough to make the noise tolerable.  I've tried moving the PS deck around with minimal improvement.  This just doesn't seem to fit Elecraft's philosophy of a quiet operating environment.  Why do these fans have to operate at full throttle when there is minimal current draw from the rf deck?  Why do these fans create such a piercing high-pitched note?
>If there is no response from Elecraft, what have other ops done--short of moving the PS into an adjoining room--to mitigate the scream?
>Thanks,
>73 Eric WD6DBM
>
>Sent from Yahoo Mail on Android
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