Parts/Service for SD-AT50

Name: Parts/Service for SD-AT50
Brand: SHARP
Availability: InStock

Brand: SHARP

Category: Audio

Document Type: Parts/Service

Language: EN

Uploaded: Nov. 21, 2025, 7:06 p.m.

Manual Publish Date: 2002-01-01

AV Control Unit Operation

Controls audio/video input selection, volume, sound modes, and timer functions. Features digital and analog inputs for various sources like DVD, CD, TV, and VCR.

Subwoofer/Amplifier Unit Operation

Provides amplification for the home theater system, including power output to front, center, surround, and subwoofer speakers. Features system control connections.

Satellite Speaker Operation

Deliver audio output. Can be installed vertically or horizontally using supplied antislip cushions to prevent sliding.

Remote Control Operation

Enables control of various functions including power, input selection, volume, playback, sound modes, and DVD/CD specific controls from a distance.

Troubleshooting and error codes

Malfunction/Symptom	Troubleshooting Steps
Abnormal drop in output voltage of each regulator (below approx. 1.5 V)	Connect measuring device to regulator output. Turn on unit. If voltage is extremely low, regulator or circuit is defective.
Output offset overvoltage of the 1-bit amplifier (above approx. DC 2 V)	Adjust output offset voltage. If protective operation still activated, check output transistors (QA100-QA303).
Mains overvoltage of the 1-bit amplifier (above approx. DC 5.5 A)	Unit functions properly if power is supplied after removing main power supply connector. Adjust output offset voltage after repair. If protective operation still activated, check power supply detection circuits (QA410-QA415).
Defects in the cooling fan or its drive circuit (when stopped)	Connect measuring device to pin 21 (FANLOCK) on IC701. Ensure fan motor rotates properly. Check for obstructions, motor defects, or issues with the drive circuit (Q830).
PROTECT/OFFSET Detection Line Disconnection	Caution: If disconnected, protective operation will not function. Do not disconnect unless the cause is identified. Abnormality detection may be difficult with a tester due to rapid voltage changes.