Rubens

I see the amplitude changing on the power indicator within another transceiver on ft8, so I wonder if the simple indicator is not following the modulation. I concur with Evan to have you evaluate it on cw, and watch your transmit frequency (I usually fix my transmit frequency to one spot, and only move to other ops frequency when he doesn't respond).

If you want to check adjustment of your ssb modulation you need a simple audio oscillator.

Curt wb8yyy