SERVICE MANUAL
LBB 3310/00, 3330/00 and 3331/00
page: 10
Date of issue:
4822 861 11006
July 1998
Of importance is that for all measurements the distance
between loudspeaker and microphone is equal.
Ä
Measure the audio level on the AC meter.
Take this level as ref. for the CCS800 units to be adjusted.
Repeat the ref. measurement for a check with other unit(s).
The factory level adjustment is ±0.5dB
5
Remove the factory adjusted unit and place
the unit for adjustment in the same position.
Do not change the audio setting adjustments.
Ä
Read the audio level on the AC meter.
Ä
Tune R72 to the audio ref. level as measured
before.
Please note that in the bottom plate is a small hole for access to R72.
Never adjust R72 when the microphone of the unit is factory tuned!
9. Maintenance
•
•
Preventive maintenance
Regular preventive maintenance is not necessary.
Depending on the usage the equipment may need cleaning.
•
•
Corrective maintenance
Defective units can be repaired or replaced by a new one. Repair of a discussion unit has to be carried out in a
cost
effective way, with a high quality and without using special tools and equipment.
•
•
Electrical
The chapter ‘Diagnostics/ Fault finding’ describes how to measure possible defects in circuit sections.
Replacement on board level is required when defects in the digital sections of the board(s) are
determined.
From other circuitry’s are some components available for replacement.
•
•
Mechanical
A selection of mechanical components is available to replace damaged and wear out parts.
•
•
Microphone
The microphone with belonging stem is not repairable. When found defective the complete microphone stem assembly
has to be replaced.
Summary of Contents for CCS 800
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