According to :
I have a single pole switch outlet combo device in my kitchen. The
switch started to make a loud pop when the light was turned off, not
on. I tried to replace the device and here is what happened. There
are three wires in the box. I know the one hot and the other are
neutral. No ground wire. I wired hot to hot, and the neutrals to the
other two silver and then light brass screw. Powered on and the
switch worked, no plug, unless switch was on. Reversed the two
neutrals and now only outlet works, no switch. What did I do. There
are two screws for the hot, one labeled common and the other unlabeled
and they are both connected by a brass tab. Help. The previous combo
was not grounded, two pronger, 10A. New is grounded 15A.

Is this receptacle supposed to have one switched and one unswitched
outlet? If so, there have to be two hots - one on all the time, the
other controlled by the switch. They're both connected to the
"hot" side of the outlet, but you have to break the tab.
--
Chris Lewis,

Age and Treachery will Triumph over Youth and Skill
It's not just anyone who gets a Starship Cruiser class named after them.