[Elecraft] running an external amp?

[Vic K2VCO]

K6MR wrote:
> Not sure if you mean the KAT-2 or the KAT-100, but I drive both my amps 
> with the KAT-100s in line from both radios.  I don't know how the tuner 
> would know the difference between an antenna or an amplifier input 
> network.  I just let the tuner cycle (it's real quick) using the tune 
> button the first time I activate the amp.  Then use the keyer to tune 
> with dits.

The KAT2 and KAT100 are pretty similar.  The difference between an 
antenna and an amplifier input network is that the impedance seen when 
driving an amplifier changes as the amplifier is driven harder!  So you 
can get a sort of unstable condition in which the tuner tries to match a 
varying impedance.  This is probably not harmful since you are tuning at 
reduced power, but it's not clear that the tuner will find an 
appropriate match.  That's why I recommend tuning the K2 into a 50-ohm 
dummy load first, and then using it to drive the amp.

-- 
73,
Vic, K2VCO
Fresno CA
http://www.qsl.net/k2vco