Good post here
New Palomar HD250FET and HD450FET
from what I've read on the net..they ( FET250HD and the FET450HD )
put out about 4 1/2--5 watts for every watt put in.
Spec's on the amp here ( this is also where I bought mine )
http://www.epoweramps.com/linear_amplifiiers.htm
------------in MY case----------
I have never checked mine with a meter ( don't have one )..but using real world LONG distance radio checks..it brings me up and average of 2 S units on SSB and AM.
NOTE: I'm NOT able to drive the Palomar FET450HD to it's full output..( I'm only driving it with 63-66 watts.)
It works great on SSB..AM and FM
Also in MY case..it really likes a long jumper between radio and amp. ( I'm using 18' )
the shorter jumpers ( 2'..3'..6'..8'..12' ) caused the amp to chatter and sometimes not want to un-key.
A few pic's of my " Palomar FET450HD "
I added a fan to keep it cool.....Masscool 140mm 2 Ball Bearing Silent Case Fan
And a very small toggle switch for the fan....Radio Shack #275-0645
I cut off the fan's computer wiring harness and added the switch and new wiring....then covered the switch and wiring with hot glue to keep everything in place.
Then added some 1 inch rubber feet from Lowes....Grippers #0054238
.