[ICOM] External Fans

[Roger (K8RI)]

On 4/10/2012 4:14 PM, Bob DiPippo wrote:
>
> Probably not a bad idea to also open the radio every 3-5 years and inspect
> the fan and the PA board components for dust. Remove that dust with a soft
> brush or an air compressor set at low PSI.

If you have pets and particularly cats, and the ham shack is carpeted, 
I'd clean it out a minimum of once a year.
The first year, just keep checking it monthly.  You may or may not make 
it a year before deciding to clean it. If it's still clean after a year 
(Nothing here makes it that long in my den) then just keep checking 
every few months until you can physically see a light build up. It 
doesn't take much to add resistance to the heat transfer.

Years ago I had a Pentium shut down from over heat. When I pulled the 
CPU (it had a shroud on it) the shroud was actually packed solid with 
very fine talcum like dust
Now days they use much larger fans that run at much lower speeds.  Those 
old, high speed fans were real dust catchers.  Even though the new ones 
move much more air, it's at a lower velocity and the dust does not 
collect on every sharp corner.  That and all 4 of my computers have 
filters on all the air inlets. Each is a full size tower, with a total 
of 7 fans.  I have 2 in the den and 2 in the shop right next to the 
rigs.  I let my wife worry about hers, but it seems as if I'm the one 
who always has to fix it.

Surprisingly, out in my shop the rigs seem to say clean even with all 
the crud in the air from welding. OTOH I do run a whole shop fan/ 
filter.  It's a home made affair from a 20 X 20 inch window fan with a 
4" thick pleated filter just taped to the back.  Before the fan the 
whole shop would turn blue and with much welding it would be difficult 
to see the full 40 foot length clearly. After the fan which runs 24 X 7 
the air stays clean even while welding for prolonged periods.

Typically canned air and a small vacuum cleaner will work fine for 
cleaning the rig. Be careful about bumping "things" with the vacuum 
cleaner, or spraying liquid out of the canned air container.

I find it really tempting to just use the air hose  at the typical 90 
psi the regulator is set at (It'll go to about 140 psi) , but this is 
not good for the equipment. It'll clean really fast, but it'll also blow 
small particles (and some not so small) into places where they can do 
damage and it's really hard on fan bearings if you spin one up.  You can 
easily hit 30 to 50,000 rpm on a fan designed for maybe 1000 to 2000 rpm 
and the blades can come apart from the G forces at those speeds.

73

Roger (K8RI)