1. Introduction
Thank you for choosing the GUY-TECH AC Adapter. This manual provides essential information for the safe and efficient use of your new power supply. Please read these instructions carefully before installation and operation, and retain them for future reference.
2. Product Overview
The GUY-TECH AC Adapter is a high-quality, non-OEM replacement power supply designed to provide reliable DC power to compatible Yamaha keyboards. It features a durable design, a convenient LED indicator, and comprehensive protection mechanisms.
Key Features:
- Compatibility: Specifically designed for Yamaha PSR-18, PSR-11, and PS-300 keyboard models.
- Input Voltage: Supports worldwide input from 100V to 240V.
- Output Voltage: Provides stable 9 Volts DC output.
- Safety Protections: Includes Over Voltage, Over Current, and Short Circuit output protection.
- LED Indicator: A built-in LED light indicates power status.
- Cable Length: Features a 5-foot (approximately 1.5 meters) power cord for flexible placement.

Image: The GUY-TECH AC Adapter highlighting its 5-foot cable length and LED indicator feature.
3. Compatibility
This AC adapter is compatible with the following Yamaha keyboard models:
- Yamaha PSR-18
- Yamaha PSR-11
- Yamaha PS-300
Important: Before connecting, please verify that your keyboard model is listed above to ensure proper functionality and prevent damage.
4. Setup Instructions
Follow these steps to correctly set up your GUY-TECH AC Adapter:
- Unpack: Carefully remove the AC adapter from its packaging.
- Inspect: Check the adapter and cable for any visible damage. Do not use if damaged.
- Connect to Keyboard: Locate the DC input jack on your Yamaha keyboard. Insert the barrel connector of the GUY-TECH AC Adapter firmly into this jack. Ensure a snug fit.
- Connect to Power Outlet: Plug the AC adapter's power prongs into a standard wall outlet (100V-240V).
- Verify Power: The LED indicator on the adapter should illuminate, signaling that power is being supplied.
Your keyboard is now ready to be powered on.
5. Operating Instructions
Once connected, the GUY-TECH AC Adapter operates automatically. The primary function is to convert AC wall power to the appropriate DC voltage required by your compatible Yamaha keyboard.
LED Indicator:
The adapter features an LED light. When the adapter is properly plugged into a live wall outlet and receiving power, this LED will light up. This provides a quick visual confirmation that the adapter is functioning and ready to supply power to your device.
6. Maintenance
To ensure the longevity and optimal performance of your GUY-TECH AC Adapter, follow these maintenance guidelines:
- Storage: Store the adapter in a cool, dry place when not in use. Avoid extreme temperatures.
- Cleaning: Disconnect the adapter from both the wall outlet and the keyboard before cleaning. Use a soft, dry cloth to wipe the surface. Do not use liquid cleaners or solvents.
- Cable Care: Avoid bending or kinking the power cord excessively. Do not place heavy objects on the cable.
- Handling: Always grasp the plug when disconnecting from the wall outlet; do not pull on the cord.
7. Troubleshooting
If you encounter issues with your GUY-TECH AC Adapter, refer to the following common problems and solutions:
| Problem | Possible Cause | Solution |
|---|---|---|
| No power to keyboard / Adapter LED off | Adapter not plugged in correctly Wall outlet is not active Damaged adapter or cable | Ensure adapter is fully plugged into wall and keyboard. Test the wall outlet with another device. Inspect adapter and cable for damage. If damaged, discontinue use. |
| Keyboard not functioning correctly | Incorrect adapter used Keyboard malfunction | Verify adapter compatibility with your specific keyboard model. Consult your keyboard's manual for troubleshooting. |
8. Specifications
- Input: 100V - 240V AC, 50/60Hz
- Output: 9V DC
- Connector Type: Barrel Connector
- Cable Length: Approximately 5 feet (1.5 meters)
- Special Features: LED Power Indicator, Over Voltage Protection, Over Current Protection, Short Circuit Protection
- Item Weight: Approximately 5 ounces (141 grams)
- Included Components: 1 x Charger
9. Warranty and Support
For any questions, concerns, or support regarding your GUY-TECH AC Adapter, please contact the manufacturer or your retailer. Refer to your purchase documentation for specific warranty details and contact information.