[Elecraft] KPA100 Fan

[JIMMY D HARRIS]

Hi,

Yesterday I participated with my K2/100 in the Pike Special Event station 
here in Colorado Springs, Colorado.  It was in observance of Zebulon Pike's 
bicentennial discovery of Pikes Peak.  We were in a terrible location in a 
downtown valley with antenna restrictions imposed by the city Parks and 
Recreation department as the trees are older than the bicentennial.  
Propagation on 20 meters was very bad from our perspective.

Now to my point.  We were outside in 90 degree plus temps for over four 
hours.  We were running PSK31 and SSB.  PSK was kept below 25 watts.  The 
fan on the KPA100 did not come on the entire time.  I had it set for LoHi in 
the KPA100 menu.  So it should have at least been on low speed all the time. 
  The heat sink got very hot....almost too hot to touch.  A couple time I 
though I smelled hot electronics.  The PA HOT message never appeared.

To add complications when I got home it worked as advertised in my cool 
basement.  I did find the temperature calibration was set at 11 degrees 
centigrade (51 degrees f).  Must have set it during the winter when the 
basement gets chilly.  I reset it to 23 degrees centigrade.  (71 f).  Does 
anyone know of any mystery problems or other legacy fan problems with the 
KPA100?  In a couple weeks I plan to disassemble it and have a look after I 
finish another K2 for an acquantance.  The schematic nor circuit description 
does not address the fan itself as I can find.  There is a "T sense" circuit 
but how the fan ties in is not shown as I can find.

Your comments and thoughts will be very welcomed.

Jim, AB0UK
K2/100  S/N 4787