[Elecraft] K2/100 - Hi Curr and loss of power control - help! de VK7JB

[Don Wilhelm]

  John,

Yes, that is the symptom of damaged diodes D16 and D17.  There is also 
the possibility that U5 and or U6 is not responding properly, but if you 
measure no voltage drop across those diodes, they are for certain 
toasted.  Start with the diodes, and after that we can move on to the 
other components if you still have trouble.

73,
Don W3FPR

On 6/17/2011 1:59 AM, VK7JB wrote:
> Hi Group,
>
> Using my K2/100 #6998 on 20m SSB phone today, running it into an
> experimental small loop antenna.  SWR was 1.5:1.   Then:
>
> Hi Curr warning on LCD - shows continuously in TX.
> Maximum power out (>100W) independent of power control setting
> LED Bargraph stopped displaying RF output (ie no bars lit) despite>  100W
> output measured on external power meter.
>
> Disconnected antenna and attached dummy load - same symptoms.
>
> Could I have somehow fried D16&  D17 in the KPA100?  I checked these diodes
> in-circuit with my multimeter "diode test" function and there is no voltage
> drop across either.  Does this mean they've both failed open?
>
>