Adcom THX GFA-7000 - Manual (Page 7)

FRONT PANEL
0 On/Off Switch
The On/Off Switch controls power to the power transformer and circuits of the GFA-7000.
Whenever the GFA-7000 is energized the Power LED (O) will glow. To turn the GFA-7000 on,
press the push-button. It will remain in the “engaged” position while the unit is energized. To
turn the GFA-7000 off, press the push-button in and release and it will move to the
“disengaged” position.
O Power LED
This LED will glow whenever the On/Off Switch (©) is turned on and the GFA-7000 is
energized. The Power LED indicates that there is AC voltage being fed to the amplifier, but it
does not signify that all the amplifier’s circuits are in operation. If, for example, one of the
Thermal Protection LED (©) glows, that amplifier channel will not produce sound even though
the Power LED may still glow. When the GFA-7000 is turned off, the Power LED will take some
time to fade out completely. It may take up to 30 seconds to fully extinguish.
Additionally, the internal power transformer is provided with a thermostat which will
interrupt power into the transformer if its temperature exceeds 125°C. This high temperature
will seldom, if ever, be encountered unless the amplifier is subjected to abnormal conditions,
such as operation into loads of less than 3 ohms at very high listening levels, etc. If the AC
Fuse (O) is not blown, the Power LED is out, and the Thermal Protection LED (©) does not
glow, this would indicate that the thermostat within the transformer has opened.
Once the temperature within the transformer decreases to a normal level, the thermostat
will reset itself automatically and normal operation will resume. If you are to avoid continually
tripping the thermostat in the transformer, you must reduce the sound level demands, correct
the load impedance of the loudspeakers, or both.