[Elecraft] K2-100 ATU

[Hans Bonnesen]

Hello Elecraft,

After a couple of years of flawless operation my K2-100 ( separate units) is starting to act up.:

A) At first I noticed that when pushing the “tune” key, that ATU of the 100 watts unit caused the relays to clatter in the normal way
but after finding the 1:1 setting, the tuning condition was not concluded, and I had to switch off the set completely and start anew.
Mostly it went well and the tune condition stopped automatically, as it should. 

BUT

B) To-day pushing the “tune” key did not cause the built-in ATU of the 100 watts unit to start its clattering. 
The SWR  reading ( lights)  went all the way to the right, and stayed there.
Naturally I switched off the set instantly , while in a split second I noticed the “Hi-current “ displayed.
Using the Ant 2. position going to a 1000 watt dummy-load did not change the malady..
++++
Disconnecting the 100 watt unit completely, I set up the K2 in its barefoot condition.
The built-in ATU of the K2 worked completely normal.
++++
Conclusion: Presumably something has developed in the SWR circuits of the 100 watt unit.
Where should I look ?

73’s OZ5RB

Hans Elfelt Bonnesen