I have an older house in SE PA and am observing something with an
electrical circuit that it not intuitively clear to me. First let me
describe my panel configuration;

The feed into the house comes into a main circuit breaker box. There
is a sub panel hanging off the main breaker panel. Out of this sub
panel is fed (among other things) a 20-amp circuit feeding some
recessed lighting fixtures and ceiling fan in my den.

The circuit comes straight from the sub panel to a junction box in the
ceiling. From there it feeds a switch box on the wall containing two
single-pole switches (one for the lights and one for the fan). The
neutral is not carried down to the switch box. Everything works great
with the exception of the problem described below.

When the switch is in the closed position, I get a voltage reading of
120-volts (reading both to neutral and ground from the "hot") - which
is what I expect. However, when the switch is in the open position I
get a reading of about 30 volts (reading both to neutral and ground
from the "hot") - which I do NOT expect. Can anyone lend some wisdom
here as I am a bit stumped.

As I type this it occurs to me that the switch might be bad and that I
should check this before proceeding much further. It is a brand new
switch but Occam's Razor tells me to start there.

Thanks in advance for your time . . .

L