Anyone have a schematic on this unit OR the whole service manual?

This one seems to have some sort of Power Supply problem. No frequency shows
up, no or weak audio. When it is turned off and on real quick, sometimes, it
will seem to reset, and work - albeit the frequencies in memory are gone. I
have resoldered the Solder Joints off of the DC jack, which were loose.
Checked a couple components, not sure now where to look with out the
schematic. Any ideas?