AKG Acoustics WMS 4000 Troubleshooting Hints, Troubleshooting hardwire and wireless microphones

AKG WMS MULTICHANNEL TECHNOLOGY

HOW MULTICHANNEL TECHNOLOGY WORKS

TROUBLESHOOTING HINTS

Troubleshooting hardwire and wireless microphones

1. Problem: no sound (microphone does not function)

	Possible cause	Hardwire mic	Wireless system	Remedy (hardwire mic)	Remedy (wireless system)
	Power supply	Check whether …	Check whether …	> Switch phantom power on or replace	> Switch power to receiver and
		• phantom power on mixer is on	• power to receiver and transmitter is	battery	transmitter on or replace batteries
		• battery is o.k. (C 1000 S only)	on and batteries are o.k.
	Cable/radio link	Check whether …	Check whether …	> Connect cable
		• both cable ends are connected	• transmitter (mic) and receiver		> Set same frequency on transmitter
			are set to same frequency		and receiver
	Signal path	Check whether …	Check whether …	> Open mic channel, set gain to
		• mic channel is open, mute and	• transmitter signal reaches receiver	drive input correctly	> Open mic channel, set gain to drive
		preattenuation switches are out, and			input correctly, set receiver squelch
		gain is set correctly on mixer			threshold to minimum
2. Problem: poor audio
	Possible cause	Hardwire mic	Wireless system	Remedy (hardwire mic)	Remedy (wireless system)
	Weak signal	Check whether …	Check whether …	> Clean contacts (use contact spray)	> Reduce distance between
		• corroded contacts, dry solder joints	• transmitter is out of range		transmitter and receiver
		cause excessive attenuation	• signal is attenuated by objects		> Reposition transmitter/receiver
			or people		(especially antennas)
					> Use active (directional) antennas
					> Use booster(s)
	Hum, whistle, or	Check whether …	Check whether …	> Change cable routing	> Select other frequencies
	other noise	• stray magnetic fields induce hum in	• there is intermodulation or	> Eliminate interference sources	> Switch off unwanted transmitter
		cables (crosstalk from parallel	interference (spectrum analyzer)	> Keep away from RF sources	(if possible) or increase distance
		lines), or ground loops, monitors,	• signal is jammed by unwanted high-		from interference source
		fluorescent lighting, or transformers	power transmitters (TV/radio station)		> Keep away from interference sources
		degrade the signal	• there are any sources of interferen-		> Reduce RF output
			ces (computers, lighting, switching		> Keep transmitter at least 2 feet
			power supplies)		(1/2 m) away from metal fabric
			• RF output causes is too high/low		and loose coins
3. Problem: signal quality deteriorates on movement
	Possible cause	Hardwire mic	Wireless system	Remedy (hardwire mic)	Remedy (wireless system)
	Dropout or	Check whether …	Check whether …	> Fix cable strain relief	> Reposition transmitter/receiver
	deep fade	• cable was accidentally disconnected	• transmitter is out of range		(especially antennas)
			• signal is attenuated by objects		> Use active (directional) antennas
			or people
			• there is a permanent line of sight
			between transmitter and receiving
			antennas
	Extremely	Check whether …	Check whether …	> Repair solder joints and/or equip-	> Switch off unwanted transmitter
	inconsistent	• any contacts are loose	• transmitter is out of range	ment	or increase distance from source
	signal quality	• there are any dry solder joints	• signal is attenuated by objects		of interference
		• microphone and/or cable is	or people		> Select clean frequencies
		mechanically damaged	• there are any unwanted local		> Reposition receiving antennas
			transmitters (e.g. intercom)		> Use active (directional) antennas
					> Use booster(s)

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