Radio Shack PRO-84 User Manual page 12

Make sure the power is turned off.
If the adapter has a voltage switch, set the switch
to 6V.
Insert the Adaptaplug into the DC adapter's cord
so it reads TIP +. Then, insert the Adaptaplug into
the scanner's DC 6V jack.
Plug the other end of the adapter into your
vehicle's cigarette-lighter socket.
If rechargeable batteries are installed and
ALKALINE/RECHARGEABLE is set to
RECHARGEABLE, the adapter powers the scanner
and recharges the installed batteries at the same
time.
Note: If the scanner does not operate properly
when you use a DC adapter, unplug the adapter
from the cigarette-lighter socket and clean the
socket to remove ashes and debris.
The Basics 12