[Elecraft] Thermal control for Q1 / Q2 in KPA100?

[David Cutter]

Also finger grills and panel slots create turbulence which can drastically 
reduce flow.  For a common or garden 'computer' type of fan, a dust filter 
can practically stop air flow all together, so, choose with care.

David
G3UNA

----- Original Message ----- 
From: "Geoffrey Mackenzie-Kennedy" <gmk at gm4esd.fsworld.co.uk>
To: "Elecraft Discussion List" <elecraft at mailman.qth.net>
Sent: Thursday, December 07, 2006 1:05 PM
Subject: Re: RE: [Elecraft] Thermal control for Q1 / Q2 in KPA100?


> David G3UNA wrote:
>
>> Consult the fan design and see how its rating varies with pressure on one 
>> side or the other.  The air flow rate drops dramatically from its 
>> headline advertised value as soon as it encounters any back pressure in 
>> front of it and with restriction on the inlet side.
>
> -------------------------------------------------------------------------------------
>
> The restriction on the inlet side that David mentions would include the 
> effect of any air filter. This might appear to be obvious, but it does 
> mean that the filter has has to be cleaned when necessary to maintain 
> proper air flow, a task often forgotten. I believe that air cooling 
> systems should include air filters whenever possible.
>
> 73,
> Geoff
> GM4ESD
>
>
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