Yes and add a bit of IM generated by some of the solid state amps to the
3KHz wide SSB signal and it is now 6 or more KHz wide. Rapidly I might add.
Unfortunately, the solid state amps have a very sharp knee between being
clean and transitioning to being a distortion generator. Oh it rarely
affects the fundamental SSB signal but transmitted bandwidth increases
rapidly. Unlike the old fashion tube amps, specially those that use tubes
developed for AB linear service, these have a very soft knee and can be
somewhat over driven or lightly loaded with little observed problems. As
was said, if it is in the passband, you're gonna hear it.
As to why heard on the Orion and not on the FT, as someone suggested, was
the 600 Hz roofing filter actually activated? An oversight on this point
makes all the difference in the world. And then is the point of AGC
threshold where the gain under certain conditions is actually increased in
the processing chain.
73
Bob, K4TAX
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