[Harlan]

Hi,

The red wire would be the "signal" or "hot" lead, the black would be "common", (sometimes referred to as ground) and the braid
is often "grounded" to the chassis / frame at the end going into
the radio/amplifier.
Sometimes the braid is left unconnected at the cartridge end.
Just need to be sure it doesn't touch the red wire/terminal or
it will just kill (short out) the cartridge signal. It is also possible
that it could be conneted to the arm itself if metal or in some
cases may also be connected to the black wire or terminal altho
least likely. It mainly acts as a "shield" to reduce or eliminate
pickup by the hot wire of stray signals or noise that would cause
interference in the sound.
Again, since I am new to some of the methods used "way-back",
I'm not totally sure and someone else may have a better answer
for you. The main point is that initially it won't matter if the braid
is not connected at the cartridge end. If things work with good
volume but you have some other noise or hum with it, then the
braid may need to be just connected to the black or metal of
the arm. Hope this helps!
Best regards,
Harlan