[Elecraft] Elecraft Power Ratings

[Dave Hachadorian]

At 45 degrees Celsius, the K3 fans were probably running at speed 2.

I don't like to hear the fans throttling up and down, so I set mine to run 
at speed 4 before yesterday's RTTY contest. Not only did they run at 
constant speed, keeping things cool, but they gave me the feeling that I 
was running big power with all that fan noise. The noise at speed 4 sounds 
quite pleasant to me.

The following is a copy of a reflector posting I made on 20090312:

I did an experiment on my two K3's - key down at 100 watts
for four minutes while noting PA Temp and fan speed. Both K3's
behaved
identically and both leveled off at PA Temp = 64C after
about 3 minutes. For the record, here are the results (best
viewed with Courier font):

Time   Temp  Fan
0:00    26C    0
0:26    37      1
0:44    41      2
1:19    50      3
1:45    55      4
2:40    60      4
2:50    62      4
3:15    64      4
4:00    64      4

Room temp was 77F.

According to the manual, the PA is set to drop into bypass at
84C, so it didn't even come close.


Dave Hachadorian, K6LL
Yuma, AZ




-----Original Message----- 
From: Jim Brown
Sent: Sunday, February 27, 2011 11:01 AM
To: Reflector Elecraft
Subject: [Elecraft] Elecraft Power Ratings

I ran an NAQP RTTY contest yesterday, and after CQing on 20M for a while
as it was closing, looked at the PA temperature.  It was only 45 degrees
C, well below the point where fans would turn on and/or speed up to
provide more cooling.  The K3 is not alone in conservative design -- my
vintage IC746, which I bought many years ago to use on 6M and 2M,  is
also rated for 100W in keydown modes, even on 2M.

73, Jim K9YC