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Zone 2 does not play digital inputs
Zone 2 can play analog sources independent of what is
playing in the Main Zone. It cannot play from a digital-
only source unless that input is selected and playing in
the Main Zone. To play a source such as a DVD player
in Zone 2 independent of the Main Zone, make sure you
connect the player’s L/R analog audio output to the PT-
7020A too.
External Amplifier(s) Shut Down (Often or
Prematurely)
Check the following:
Make sure each speaker’s average impedance is not less
than your amplifiers can safely handle.
The amplifier(s) have good ventilation, no vents are
covered.
Try setting all the speakers to Small, and let your
subwoofers handle the heavy bass.
Check that the amplifier(s) power output is a good match
for your speakers. If your speakers are inefficient,
consider using larger power amplifiers.
Make sure all wiring is correct and there are no shorts.
PT-7020A “Locks Up” (No Response)
Unplug AC power momentarily, and press Power to turn
back on. If this does not work, try the reset procedure.
Problems Updating PT-7020A Firmware
Check that the serial cable is connected correctly between
the PT-7020A and your computer’s serial port.
If you have a Palm Pilot™ or similar device with
“HotSync™” or its equivalent, you may need to disable
this software before proceeding. This software ‘seizes’
control of a serial port on your machine and prevents
the Sherbourn software from accessing that port. Use
another port or disable HotSync.
For additional information regarding technical issues
encountered with updating the firmware of the PT-
7020A, visit the Sherbourn website at:
www.Sherbourn.com.
“Hum” Noises
This problem is more than likely caused by a “ground
loop” in your system, rather than a fault in the PT-7020A.
Follow these steps to isolate the main cause of the hum,
there may even be more than one.
Remember to turn off all components in your system,
including the PT-7020A, before disconnecting or
connecting any cables.
Disconnect the following items in order, and check each
time if the hum has gone away:
Disconnect all cables which come from outside the room,
such as cable TV, satellite TV, or roof top antennas. Make
sure that they are disconnected where they first enter
the room, so they are making no connection to the PT-
7020A or the TV, or any other component. If the hum is
caused by the cable TV line, then you will need a “ground
loop isolator.” This is an inexpensive device fitted in
line with the coaxial cable feed. Contact your cable
company or your Sherbourn Dealer.
Disconnect all connections from the PT-7020A to your
TV.
Disconnect any component which has a grounded power
cord.
If the hum persists, disconnect all the source components
one at a time from the back of the PT-7020A, until you
identify the problem. (Ground loop isolators are available
for audio lines and video. Ask your Sherbourn Dealer or
a professional home entertainment integrator for
assistance)
Try moving the speaker cables away from any power
cords. Try just one speaker, connecting it to different
channels and see if an amplifier channel is bad.
If you are still having a problem, remember that
Sherbourn’s technical support staff will assist you.
Other Probable Causes of Noise
Speaker noise may also be caused by interference or
noise on your AC line. Make sure there are no large
appliances sharing the line, or halogen lamps or light-
dimming Triac devices.
Try connecting your system to another AC socket on a
separate line.
If the hum is heard from within the PT-7020A and not
through the speakers, this may also be caused by
interference on the AC or DC lines. The power
transformers may turn this interference into an audible
noise. Internal hum can be made worse by a shelf or
cabinet resonating, so try moving the PT-7020A to
another shelf.
Try moving your components further away from the TV,
especially if you ever notice the screen has changed color
in the area closest to the component.
If you have very high efficiency speakers, these may
tend to reveal noises which other speakers do not.
Summary of Contents for PT-7020A
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