Re: Cooling fan Shroud

Bob Lunsford <nocrud222@...>

Try a 2W resister in series with some conventional fans and
the noise is much less. Run it a while and check to see that
the fan is not getting too warm. The resistor value may be in
the 500-1000 ohm range. That's where I would start, anyway.

It's nice to have a few fans of various sizes on hand. They
are sometimes seen at hamfests. Most cost between $1 and
$5 which is not all that much to pay for a small fan. I have
also rescued some from computer-type power supplies and
depending on size of power supply, I have some that range
between 2-in and 4-in. Most are designed to run for years.

Bob — KK5R


On Thu, 1/17/19, Jim Sheldon <@W0EB> wrote:

Subject: Re: [BITX20] Cooling fan Shroud
Date: Thursday, January 17, 2019, 10:02 AM

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originally used a 4" fan I got off an old computer
power supply on the back of that same style case -
electrically and acoustically VERY noisy.  Asked Al
yesterday about his little fan and ordered one.  It will be
here Friday.  Now I have to find another case like that one
so I can do a scratch JackAL/uBITX build with the 5"
Jim -

------ Original Message ------
From: "Albert Peter" <albertfpeter@...>
To: "" <>
Sent: 1/17/2019 8:43:13 AM
Subject: Re: [BITX20] Cooling fan Shroud

I also looked for a fan
solution on my uBITX.  I tried several salvaged from
computer parts, but all were too noisy  I finally came up
with this one:Noctua NF-A4x20 PWM Premium-Quality
Quiet 40mm Fan – $14.99 from Amazon.  A bit pricey, but it has virtually
no acoustic noise and very little, if any electrical
noise.  Mounted on the side of my case and now everything
is cool as can be.AlAC8GY

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