Extron Electronics MPX 423 A - Manual (Page 26)

Operation, cont’d
MPX 423 A • Operation 3-8
PRELIMINAR
Y
Adjusting the input audio level
The audio level of each input can be adjusted from -18 to +24 dB. The factory
default level is 0 dB.
There is only one audio settting which is applied to both the left and right audio
inputs of the selected input device.
Audio level settings are stored in non-volatile memory, and retained through a
power cycle.
When performing the procedure below, you may monitor the Input Audio/Gain
Attenuation level via RS-232 using HyperTerminal (see chapter 4).
To enter the audio adjust mode and adjust an input audio level:
1 . Press and hold the Mute button for 2 seconds. The I/O Audio LED and one of
the input LEDs (ex: input 7) flashes indicating the audio adjust mode.
2 . Press the desired input button. The selected button’s LED begins flashing.
C There is no indication of the audio level available by viewing the front
panel. You may monitor the volume level adjustments via an RS-232
connection and HyperTerminal (see chapter 4).
C Pressing an input button while in audio adjust mode will
activate / de-activate a tie.
3 . Turn the Volume control knob clockwise to increase volume and
counterclockwise to decrease the volume level of the selected input.
4 . Press and release the I/O button or wait 30 seconds for the unit to exit the
audio adjustment mode.
C Pressing the Mute button while in audio adjust mode will activate the
mute for output 1.
Audio outputs
Balanced or unbalanced audio output is available on the MPX 423 A using a 3.5
mm, 5-pole captive screw connector, wired as shown below.
Unbalanced Input / Output
Tip
See caution
Sleeve
Tip
See caution
Balanced Input / Output
Tip
Ring
Sleeve (s)
Tip
Ring
Figure 3-4 — 3.5 mm, 5-pole captive screw audio connectors
C Connect the sleeve to ground (Gnd). Connecting the sleeve to a negative
(-) terminal damages the audio output circuits.