Extron electronic MLA-VC10 user manual Installation and Setup, cont’d Troubleshooting

Installation and Setup, cont’d

Troubleshooting

If the MLA-VC10’s LED doesn’t light:

Command/response table for SIS commands

Additional description

Response	(MLC to host)
ASCII Command	(host to MLC)

Command

Specify the % of maximum audio volume output. Example: set volume to 82% of maximum. Increment audio volume. Decrement audio volume. Show the % of maximum audio level.

X1	Vol082	X1	X1	X1
Vol		Vol	Vol	Vol

	V	82V	+V
	X1			-V	V
Volume adjustment	Set the output volume	Example:	Increment (increase audio output)	Decrement	View the volume level

audio outputs.	all audio outputs.
Mute all	Unmute

Amt1 Amt0

1Z 0Z

Audio mute (overall) Mute on Mute off

Show the status of audio mute.

Amt X2

View the audio mute status. Z

Firmware version, part number & information requests

Show the firmware version.

Ver X3

Query firmware version number Q

Show the MLA’s part #.

N60-502-01

N

Request part number

•The MLA-VC10 is not receiving power. Check the wiring at the MLA-VC10’s MLC/Power port for correct polarity. Verify that the power supply has been connected to a functional power outlet.

If the MLA-VC10’s LED doesn’t blink when volume commands are sent:

•The volume command is out of the acceptable range (0 to 100 steps).

•The MLA-VC10 is not receiving RS-232 commands correctly.

If there is no audio output

•Check the wiring at the amplifier/mixer to make sure the MLA-VC10 is connected to the correct terminals. Verify that the amplifier/mixer and speakers have been powered on.

If the output is noisy or has lots of static:

•The amplifier/mixer and MLA-VC10 are installed near electromagnetic interference sources such as appliances and large motors. Move the amp/mixer and the MLA-VC10 away from the interference source.

•The voltage control cable is too long, allowing noise to be picked up from many sources. Use a shorter cable (6 feet, max.) between the MLA-VC10 and the amplifier or mixer.

•The ground line may be noisy. Use a different, “clean” grounding source.

If the volume doesn’t change when you change the volume setting via the MLC or via RS-232 commands:

•The wiring at the amplifier/mixer terminals is reversed. Switch the leads for the ground and the control volume.

•The DIP switches are set for too high of an output voltage. If this is the case, the amplifier/mixer will output the maximum audio level all the time and will not change. Retest the amplifier/mixer’s control voltage and reset the DIP switches to match the required voltage.

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