[Elecraft] KPA100 in cold temperature

[Dominik Bugmann]

Hi,

I'd like to share tonight's results of my KPA100-in-the-fridge-test.

Since 6. Oct 2002 my K2 has a KPA100/KAT100 in an external EC-2 and I
managed more than 5700 (Contest)-QSOs.

As already reported a few weeks/months back I experince temperature problems
with the KPA100. E.g. when I participated in CQ/RJ RTTY contest it was
freezing temperature outside and my contest shack is heated to +8C while
nobody is there. The shack is in a farm area with no QRM (except the bells
hanging around the cow's neck ...).

Each time I switch on my K2/100 the fan is at full speed and the display
says "Hi PA Temp" which I couldn't believe.

Tonight I took my KPA100/KAT100-pair and placed them into the fridge for 2
hours. In the mean time I visited my neighbours and when I returned the
thermometer in the fridge showed +7.7C. The K2/QRP stayed in the living room
at +22C. I took the PA placed it on top of the K2 wired all cables and
powered on. As expected the fan is at full speed. Browsing through the menu
and "tPA says 250C". After a few minutes temp rose to 0C and the fan
switched off. As I type these lines the PA is now 20 minutes out of the
fridge and the display shows 9C and is still rising.

Workaround I used so far: Recalibrate "tPA" to a >0C level and start the
contest. Unfortunately the temp-meter (Q3) in KPA100 does not understand
negative temperature.

BTW: If you think there are now contests in sub-zero temperature. Lets
remeber 1985. VHF-Contest in March. Outside temp was -20C. Inside temp (a
wooden hut): a bit more. At that time paper-logging was they way to do it
and a soundcard that calls CQ for you was still a dream. Between two CQ
calls I took a bottle of Coke, filled a glass, called "CQ Contest ..." for
15 Seconds and tried to take a sip while somebody answered my call. The Coke
wasn't as expected; it was frozen to one block!

BTW 2: Nowadays I prefer a shack at +20C ... :-)

In the mean time: tPA is at 15C and room temp at 22C.

73 de Dominik, HB9CZF
http://www.swiss-artg.ch/hb9czf