engine starting

I own a 1969 vw bus and just had a new generator
installed. Attempted to also replace voltage
regulator but had to keep the old one on because
the new one did not work right. It was sparking
because it was not grounded right is my guess.
Anyway,  I drove it the other day and everything
was fine. I tried to drive it again and a weird sound
like a lose belt or something in the engine. The
noise did not go away.  I turned the engine off and
when I tried to turn it on, it would not start. It won't
turn over,  you can't hear anything.  The generator
light and oil light come on and that's it. I checked
the headlight and instrument panel and lights
seem to be fine. I tried to jump the battery and still
nothing. Does anyone have an idea of what the
problem might be? I read somewhere that when
change the generator, that you need a new voltage
regulator. Could this be the issue or something
else?