[AMRadio] Drake L-4B on AM

[kenw2dtc]

"BTW, I tuned the amp for exactly 1500 watts output, then reduced the drive 
to exactly 25 watts without re-tuning the amplifier"

Actually the best way is to tune for 1500 watts out and reduce the drive 
until the output is 375 watts under carrier conditions.  Also if you have 
one of those male voices that that will peak more in one direction than the 
other (if the audio is phased correctly) you must also de-rate the output 
power even more.  Naturally, a scope and an audio generator is the preferred 
way to tune up a linear under AM conditions.
 73,
Ken W2DTC

http://w2dtc.com/3cx3000f7.htm