TS-820S Has low output on USB

[KE7UTR]

I am looking at buying my first rig from a friend, A TS-820S. It works fine except that USB puts out about 2/3 the power of LSB. When on USB you have to have the mic gain all the way up to be heard. I am a new ham but my dad has been a ham for years and is pretty sharp when it comes to electronics, but he doesn't have much experience with this particular rig, so we're running out of ideas. He has cleaned a number of connections and has done some of the alignment procedures in the manual, but it doesn't seem to help. Any ideas?

[K7KBN]

I'm assuming you're taking into consideration the fact that there is no carrier in SSB, whether USB or LSB. You have to use a good PEP-indicating meter; the usual average-indicating meter just can't move fast enough to keep up with voice peaks.

A PEP-indicating meter will have either an internal power source or will be powered in some other way. Either way, measure the PEP output into a dummy load on both USB and LSB. If there's a difference, I'd look at the balanced modulator - which may have become a little UNbalanced.

[KE7UTR]

That sounds like a logical place to look. I'll let you know how it turns out. Thanks.