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DC Trigger Connection
The DC Trigger allows you to turn on your amplifier with external DC voltage sources from + 9 Vdc to
+12 Vdc. Use a two-conductor wire such as an 18 AWG speaker wire to connect the DC trigger from an
external source to your amplifier. You should first determine the + DC voltage and ground conductor
from the external source. For example, the AVC-2500 has DC trigger that uses an 1/8" mini jack where
the tip is positive and the ring is negative (ground). In this case, you would terminate one end with an
1/8" mini plug and strip off a 1/4" of insulation and use bare wire on the other end. Connect the positive
lead to the screw l12 V on the amplifier’s DC trigger connector and the negative (ground) lead
to the screw labeled GND. With the main power switch in the off (down) position, the amplifier can now
be turned on with the external DC source.
Operating Your HCA-1205A or HCA-855A
Power Switch
Manual Turn On
Press the upper side to turn the unit on manually; press the lower side to turn the unit off.
Automatic Turn On
When the power switch is in the off position, the power amplifier can be turned on with an external DC
voltage applied at the DC trigger connector on the rear panel.
AC Line LED
The AC line LED on the front panel of your amplifier will illuminate whenever AC is present at the AC
connector. This LED indicates that the AC cord is connected and that power is currently applied to the
amplifier.
Standby/Normal Operation LEDs
The red Standby LED will light when the amplifier is turned on either with the power switch or an external
DC trigger. It will stay lit about four to five seconds while the amplifier circuits stabilize. After that, the
red LED will turn off and the green normal LED will signal that the protection relays have switched off
and that amplifier is ready to operate. The Standby LED will also light whenever there is a short circuit
or other fault that triggers the protection circuitry. This may indicate one of the following conditions: DC
present at the amplifier's input, a speaker impedance overload, a short circuited speaker line, or possible
internal fault. If this LED remains lit, remove power to the amplifier and check all connections. During
this time, the protection circuits should automatically reset. If the red LED stays lit after you reapply
power, contact your Parasound Dealer, Installer or Parasound Technical Service for further advice.
Current Overload LEDs
The Current Overload LEDs for each channel only illuminates if the unit is driven past its maximum
current capacity. These LEDs are not clipping indicators, but are designed to signal when you are
exceeding the limits of your amplifier. If these LEDs light, it’s usually a sign that your speaker impedance
is too low, resulting in too much current draw from the amplifier's power supply. In most imaginable
listening situations with recommended loads, these LEDs should not illuminate.
