AKG Acoustics WMS 40 - Manual (Page 36)

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T
ROUBLESHOOTING
H
INTS
HOW MULTICHANNEL TECHNOLOGY WORKS
Troubleshooting hardwire and wireless microphones
1. Problem: no sound (microphone does not function)
Possible cause
Power supply
Cable/radio link
Signal path
Hardwire mic
Check whether …
• phantom power on mixer is on
• battery is o.k. (C 1000 S only)
Check whether …
• both cable ends are connected
Check whether …
• mic channel is open, mute and
preattenuation switches are out, and
gain is set correctly on mixer
Wireless system
Check whether …
• power to receiver and transmitter is
on and batteries are o.k.
Check whether …
• transmitter (mic) and receiver
are set to same frequency
Check whether …
• transmitter signal reaches receiver
Remedy (hardwire mic)
> Switch phantom power on or replace
battery
> Connect cable
> Open mic channel, set gain to
drive input correctly
Remedy (wireless system)
> Switch power to receiver and
transmitter on or replace batteries
> Set same frequency on transmitter
and receiver
> Open mic channel, set gain to drive
input correctly, set receiver squelch
threshold to minimum
3. Problem: signal quality deteriorates on movement
Possible cause
Dropout or
deep fade
Extremely
inconsistent
signal quality
Hardwire mic
Check whether …
• cable was accidentally disconnected
Check whether …
• any contacts are loose
• there are any dry solder joints
• microphone and/or cable is
mechanically damaged
Wireless system
Check whether …
• transmitter is out of range
• signal is attenuated by objects
or people
• there is a permanent line of sight
between transmitter and receiving
antennas
Check whether …
• transmitter is out of range
• signal is attenuated by objects
or people
• there are any unwanted local
transmitters (e.g. intercom)
Remedy (hardwire mic)
> Fix cable strain relief
> Repair solder joints and/or equip-
ment
Remedy (wireless system)
> Reposition transmitter/receiver
(especially antennas)
> Use active (directional) antennas
> Switch off unwanted transmitter
or increase distance from source
of interference
> Select clean frequencies
> Reposition receiving antennas
> Use active (directional) antennas
> Use booster(s)
2. Problem: poor audio
Possible cause
Weak signal
Hum, whistle, or
other noise
Hardwire mic
Check whether …
• corroded contacts, dry solder joints
cause excessive attenuation
Check whether …
• stray magnetic fields induce hum in
cables (crosstalk from parallel
lines), or ground loops, monitors,
fluorescent lighting, or transformers
degrade the signal
Wireless system
Check whether …
• transmitter is out of range
• signal is attenuated by objects
or people
Check whether …
• there is intermodulation or
interference (spectrum analyzer)
• signal is jammed by unwanted high-
power transmitters (TV/radio station)
• there are any sources of interferen-
ces (computers, lighting, switching
power supplies)
• RF output causes is too high/low
Remedy (hardwire mic)
> Clean contacts (use contact spray)
> Change cable routing
> Eliminate interference sources
> Keep away from RF sources
Remedy (wireless system)
> Reduce distance between
transmitter and receiver
> Reposition transmitter/receiver
(especially antennas)
> Use active (directional) antennas
> Use booster(s)
> Select other frequencies
> Switch off unwanted transmitter
(if possible) or increase distance
from interference source
> Keep away from interference sources
> Reduce RF output
> Keep transmitter at least 2 feet
(1/2 m) away from metal fabric
and loose coins
AKG WMS MULTICHANNEL TECHNOLOGY