[Elecraft] how does the fan work in the KPA100

[Don Wilhelm]

Werner,

As far as I know, there is only one temperature trigger point for the 
fan operation.
For most CW/SSB operation, the Fan Normal will do just great.
If one is operating digital modes or in intense contest situations, the 
Fan Hi/Lo setting may be best so that the fan normally runs at low speed 
and increases when the temperature reaches the trigger point.
For really intense operation in high ambient temperatures and/or 
situations where the noise of the small fan is objectionable, an 
external muffin fan mounted above the heat sink can provide extra 
cooling and in most cases will keep the internal fan from coming on.  
Take a look at www.n0ss.net for some pictures of Tom's external fan 
implementation.

73,
Don W3FPR

Dr. Werner Furlan wrote:
> here I am again with my next question. 
>
> I don't understand how the fan should work in my KPA100.
> I have set the fan to normal in the K2 PA menue. 
> Like this it is off when I switch the amplifier on. 
> It goes to fast when I operate for a certain time with high power and the 
> heatsink gets hot.
> But I did not see a low speed operation of the fan in this mode.
>
> When I switch to low/high, it always runs at low speed and probably switches 
> to high when necessary.
>
> Is it correct that there is only one temperature trigger point?
> >From reading the bias setting part of the manual, I thought the fan should 
> run at low speed also when I switch the PA into high power mode.
>
> Is it correct how it works here?
>
>
> 73! de Werner OE9FWV
>
>