[Elecraft] Probelm with KPA-100

[Don Wilhelm]

Dave,

How is receive with the KPA100 in-line?  If receive is degraded, then 
the KPA100 LPF may be the problem, but if power output is the only 
problem than the PA transistors (or the T/R switch) is the area that 
needs attention.

The first step that I would take is to check the bias adjustment - do 
the steps indicated in the manual.  Secondly, check the RF voltages at 
the input to the KPA100 and the bases of the PA transistors - if the 
bases are receiving RF, then the KPA100 should amplify.

73,
Don W3FPR

Dave White wrote:
> I have a KPA-100 that is not putting out any power.  The K2 operates 
> fine using the standard "QRP" power (up to 10 watts).  Power is good 
> and the SWR is low.  When the power control is advanced to bring in 
> the KPA-100 (relay "click"), the power reading immediately goes to "1" 
> and there is no power output.  The KPA-100 is recognized and the PA is 
> turned "ON" in the setup menu. Everything else appears normal .This is 
> a used KPA-100 and there are no obvious signs of damage; the 
> construction quality looks to be excellent. The previous owner said 
> there was no history of problems.
>
> Any quick ideas on where to start the troubleshooting process?  I have 
> some "hobbyist" test equipment and "modest to good" troubleshooting 
> skills.
>
> Thanks in advance for your help.
>
> Regards
>
> Dave White, VE6DRW
> dwds at trinustech.com
>
>
>
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