[Elecraft] KPA1500 design

[Geoffrey Mackenzie-Kennedy]

Hi Al,

Indeed one could combine amplifiers by using Hybrid Combiners.  However when 
used for SSB and especially if driven by a typical amateur solid state 
transceiver working from a 12V DC supply, a potential problem to be 
considered is that the level of Odd Order IMD products as seen at the output 
might become too high relative to PEP (or test tone).


Granted that this problem can also arise when using any other form of linear 
amplifier when driven by a similar exciter, but when using 
"Combined`Amplifiers" some (if not all) of the IMD products appearing at the 
output of each amplifier can add when combined  i.e stronger IMD products 
transmitted.  Lucky if they cancel :-)

73,

Geoff
LX2AO


On February 22, 2012 at 12:58 +0100, Alan Bloom wrote:


> You could do it with four unmodified KPA500s and three hybrid combiners.