[1000mp] Mark V high SWR with amp

[Joe Subich, K4IK]

> Well let me replay the descriptiomn.
>  
> The amps are Alpha 99 and Alpha 89.
>  
> These are modern amps.

Neither of these amplifiers has tuned inputs - bad design when 
driven by solid state transceivers. 

> SWR when running barefoot no problem on the rig.
> Once I switch on the amp the problem occurs.  Seems like 
> there is a mismatch back to the input side althought the 
> output side says everything is ok.

Alpha does some additional switching for QSK other than the 
bypass relay.  Things could look fine when the amps are off 
and/or in bypass because the relay has taken the input 
circuits of the amplifier out of play.  If your radio makes 
power "early" (before the amplifiers are ready), it is 
possible, even likely, that you have damaged some of the 
PIN diodes in the alpha input switching circuits.  
 
> I will call Yaesu on Monday and describe the situation.

I would also talk with Alpha ... 

> Only other thing  I can think of is NKE Viking tuner being 
> in line.  Gonna take it out of line and run and see what 
> happens.  Would sound strange if the tuner but could be 
> possible.

Is the tuner between the exciter and amplifier? 

73, 

   ... Joe, K4IK