[TenTec] Centurion loading

[Mike Hyder -N4NT-]

I'm new to this Centurion thing and have a couple of questions:

My loading control does not seem to have much effect on 80 meters.  I 
believe the amplifier acts as if it does not have sufficient load 
capacitance.  I base this on my finding that I can never create too much 
grid current and that the maximum output occurs with the Load control set on 
10, which I assume is maximum capacitance.  If my assumptions are wrong, 
please tell me.

I purchased the amplifier new from Ten-Tec in September 2003.  Can someone 
tell me if there have been updates to this amplifier centered around the 
load capacitance?  Are there modifications suggested on the same subject?

Thanks and 73,
Mike N4NT