4 Page/s Ref:TN0392-W180203
Product: Home Theater Front Projection Date: 10/20/03
Models: TDP-MT8U
Product Safety Precautions:
Product Safety Precautions are described in the Toshiba service manual(s) for models covered in this bulletin. All safety
precautions and checks shall be complied with before returning the equipment to the customer. Servicers who defeat safety
features or fail to perform safety checks may be liable for any resulting damages and may expose themselves and others to
possible injury.
Application: The information contained in this bulletin applies only if you encounter the
symptom(s) listed below.
Subject: New Software and Cable Routing Quiets Sounds from Projector.
Symptom: Toshiba has discovered that a very small number of TDP-MT8U projectors
may produce sounds such as a very high frequency tone or a lower
frequency buzz. The sounds make no difference to projector operation;
the projector operates normally while the sounds are heard. This tech
bulletin explains the cause of the sounds and what to do to eliminate them.
Although these sounds are rare, their cause has been identified. The high
frequency sound originates in the power supply and can be heard when the
projector powers down. As power down occurs, the projector draws no
current for a small period of time. The lack of current draw causes minor
oscillation in the power supply, resulting in an audible but soft, high
frequency tone. The lower frequency buzz is a result of oscillation in the
color wheel ribbon cable between the controller ECA and the optical engine.
The sound can be heard anytime the projector operates and may come and
go in an audible cycle.
