SB-200 is a true workhorse, it's also a SSB CW amplifier. You can certainly use it on AM but watch the grid current as it will max out fast. Better yet, make sure the metering resistors for the grid HV meter are in good condition as they tend to burn up over time leaving your meter off scale. Keep an eye on it. My last sb-200, I went through it and fixed all the problems and made it like new with full output, sold it to a fellow CB'er a short time later and he ruined a new set of tubes in just two evenings on AM.
Probably none of my business but I figured i'd share this.
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