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Explanation of the panels
Explanation of the panels
fig.DigiOutJackGuide.eps
This is optical type jack that outputs a consumer format (IEC-
60958 compliant) digital audio signal. 
By default, MONITOR L/R is patched to these jacks.
988
You can attach a commercially available security lock here. For 
details, refer to the following website:
http://www.kensington.com/
fig.BatterySlotGuide.eps
This slot contains a lithium battery that maintains the M-300’s 
clock function and preserves the mixer settings.
If the battery runs down, you’ll need to replace it. For details on 
replacing the battery, refer to “About the internal lithium battery” 
(p. 18).
Use this to connect the M-300 to an electrical ground.
927
Do not ground the M-300 to locations such as the following:
•
Water pipe (doing so may cause electrical shock)
•
Gas pipes (doing so may cause fire or explosion)
•
Telephone ground or lightning rod (hazardous if 
lightning occurs)
927
Depending on the circumstances of a particular setup, you 
may experience a discomforting sensation, or perceive that 
the surface feels gritty to the touch when you touch this 
device, microphones connected to it, or the metal portions 
of other objects, such as guitars. This is due to an 
infinitesimal electrical charge, which is absolutely harmless. 
However, if you are concerned about this, connect the 
ground terminal (see figure) with an external ground. When 
the unit is grounded, a slight hum may occur, depending on 
the particulars of your installation. If you are unsure of the 
connection method, contact the nearest Roland Service 
Center, or an authorized Roland distributor, as listed on the 
“Information” page.
You can use this power cord hook to prevent the power cord 
from being accidentally disconnected. 
For details on attaching the power cord hook, refer to 
“Attaching the power cord hook” (p. 16).
fig.ACInletGuide.eps
Connect the included power cord to the AC INPUT connector.
Do not connect any power cord to the M-300 other than the 
included one.
fig.PowerSwGuide.eps
This turns the power on/off.
945
If you need to turn off the power completely, first turn off the 
POWER switch, then unplug the power cord from the power 
outlet. Refer to Power Supply (p. 6).
fig.USBMemoryGuide.eps
You can connect USB memory to this connector.
Before you disconnect USB memory, make sure that data is 
not being written to USB memory or being read from it. If 
you disconnect USB memory while these operations are 
occurring, you risk damaging the data.
 DIGITAL OUT jack
 Security slot 
 BATTERY slot
 Grounding terminal
8
9
10
11
 Power cord hook
 AC INPUT connector
 POWER switch
 USB MEMORY connector
12
13
14
15
M-300_e.book 31ページ 2010年6月24日 木曜日 午後2時26分