[Elecraft] Burn in of KPA100

[Ron D'Eau Claire]

Yep, the amount they loosen seems to vary a lot. 

Your situation, where you don't run 100 watts much, might demand a couple of
tightenings. I don't recall seeing any reports from someone who only
occasionally runs the amp.

FWIW, after I had run my KPA100 for a few months I got involved in some
thermal testing of the K2 for a modification that was being developed. I
raised the internal temperature of the K2 by transmitting into a dummy load
at 100 watts for a half hour or more so the air temperature inside the K2
was wall above 120F and the heat sink got too hot to leave my hand on it. 

After doing that perhaps 30 or 40 times to collect data, I decided I'd
better check the screws on those transistors. They were will tight! 

That experience suggested to me that once you've gotten through the initial
period where everything gets "seated", and tightened the screws, they should
be fine over time. 

Ron AC7AC

-----Original Message-----
From: elecraft-bounces at mailman.qth.net
[mailto:elecraft-bounces at mailman.qth.net] On Behalf Of NG3V
Sent: Thursday, May 22, 2008 3:33 PM
To: ng3v at comcast.net; elecraft at mailman.qth.net
Subject: RE: [Elecraft] Burn in of KPA100


To Don, Ron, et.al.,

Thanks for the information about tightening the screws.  I just finished the
process - not 5 minutes start to finish.  They needed less than the
suggested 1/8 turn to snug 'em up, so I'll go back in a few months and
finish the job.

73,

Tom, ng3v

-----Original Message-----
From: elecraft-bounces at mailman.qth.net
[mailto:elecraft-bounces at mailman.qth.net] On Behalf Of NG3V
Sent: Wednesday, May 21, 2008 7:58 PM
To: elecraft at mailman.qth.net
Subject: [Elecraft] Burn in of KPA100

Hello group,
 
I built the 100 watt amp last summer, but can't seem to overcome the urge to
stay at qrp levels.
 
So, as I probably have only a few minutes of time at 100 watts, when should
I reset the mounting screws.  Is this like 3 months or 3000 miles or is it
strictly a matter of time?
 
Should I just pound out a few hours of tests into a dummy?
 
Thanks,
 
 
Tom

_______________________________________________
Elecraft mailing list
Post to: Elecraft at mailman.qth.net
You must be a subscriber to post to the list.
Subscriber Info (Addr. Change, sub, unsub etc.):
 http://mailman.qth.net/mailman/listinfo/elecraft    

Help: http://mailman.qth.net/subscribers.htm
Elecraft web page: http://www.elecraft.com

_______________________________________________
Elecraft mailing list
Post to: Elecraft at mailman.qth.net
You must be a subscriber to post to the list.
Subscriber Info (Addr. Change, sub, unsub etc.):
 http://mailman.qth.net/mailman/listinfo/elecraft    

Help: http://mailman.qth.net/subscribers.htm
Elecraft web page: http://www.elecraft.com