I see Jan's point - if your normal signal is operating around 1500W with a
tube such as a 4CX10000 which can handle the leading edge spikes generated
by some of the modern radios, less splatter will be generated.
However, I don't think that is really the problem:
SYSTEM ENGINEERING - Matching the exciter to the amplifier. As Tom points
out, running a 100W radio at 10W sometimes creates a new set of problems.
Transceiver output power and nominal amplifier drive should be reasonably
aligned. Using my 200W FT-1000D to drive my Alpha 91b (nominal 40W drive)
is touchy. Using the same radio to drive my 15M 3-1000Z wart hog is smooth
as silk. My friend W8WD has a FT-1000MP and an Alpha 89 - there is a
switch on the 'MP to reduce the drive to 50, which results in real smooth
operation with the 89.
SSB CONTROLS/LEVELS - How many amateurs really know how to set the controls
on their SSB rig? In the absence of a RF limiter in the radio, the mic
gain is all you can adjust; turn it up too far and some downstream stage
will flat top and splatter. With RF limiters/clippers, you have MIC GAIN,
and sometimes IN and OUT (or DRIVE) controls. The mic gain controls output
power to a point, then the limiter takes over. If the output level from
the limiter is too high, you can have downstream stage splatter again. If
the output is too low, the final output is low no matter how high you jack
the mic gain and your signal sounds like junk. Maybe no splatter, but its
still garbage on the bands.
That's the great thing about CW - fewer controls to worry about and unless
the rise/fall times are out of whack, few ways to generate a truly bad
signal.
73,
Dave/K8CC
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