Rockford Fosgate PA-1HD Owner's Manual page 7

TURN-ON CONNECTION
(RED WIRE)
(RED WIRE)
The PA-l HD / PA-l is turned on by applying Positive 12 Volts
to the red wire [#18]. Usually, the red wire is connected to the
source unit's "Accessory" or "Auto-Antenna" lead, either of
which will go positive when the source is turned on.
Although the majoriiy of high-quality automotive source units
have an Accessory or Auto-Antenna output, there are many
which may require different turn-on methods. If the source has
no Auto-Antenna lead (or if Auto-Antenna goes down during
tape operation):
a.) Find the internal switched power voltage inside the source
b) Or: install a switch in the car with one terminal connected
c)
unit and solder a lead to it. Run the lead out through the
back of the unit (being sure to use a grommet for insulation
from the case) and connect to the pre-amplifier turn-on
wire.
to +12 volts and the other to the PA-1 HD / PA-1 red lead.
Or: Connect the PA-1 HD/ PA-l red lead to accessory point
at the vehicle's fuse block. In this case the pre-amplifier will
be on wheneverthe vehicle is on. This method will allow the
system to amplify any noise and turn-on and turn-off trans-
ients, and may therefore be unsatisfactory.