When a cable modem or digital receiver stops powering on because of a missing or damaged adapter, finding the correct replacement power supply is critical. The Motorola MT20-21120-A04F AC Power Adapter provides regulated 12V DC output for compatible Motorola communication and entertainment devices, helping restore reliable daily operation.
Designed around the Motorola 503913-007 power specification, this adapter delivers 12V DC at 0.75A through a 5.5mm × 2.5mm DC barrel connector. It is suitable for replacing worn-out adapters used with compatible cable modems, digital receivers, and networking equipment where the voltage, current, polarity, and connector requirements match.
Application Scenarios
This adapter is designed for communication and consumer networking equipment that requires a low-power 12V DC external power source. Typical applications include cable modems, digital television adapters, broadband communication devices, and compatible Motorola networking equipment.
Technical Specifications
| Brand | Motorola |
| Model | MT20-21120-A04F |
| P/N | 503913-007 |
| Product Type | AC Power Adapter |
| Input Voltage | 100-240V AC, 50/60Hz |
| Output Voltage | 12V DC |
| Output Current | 0.75A (750mA) |
| Maximum Output Power | 9W |
| Connector Size | 5.5mm × 2.5mm DC Barrel Plug |
| Polarity | Center Positive |
| Protection Features | Over-voltage, Over-current, Short-circuit and Overload Protection |
OEM Replacement Compatibility
This adapter can replace the following power supply models:
- Motorola MT20-21120-A04F
- Motorola P/N 503913-007
Compatible Devices
- Motorola DCT700 Digital Receiver
- Motorola DTA100 Digital Adapter
- Compatible Motorola Cable Modem Devices
- Compatible Motorola Digital Receiver Equipment
- Other 12V 0.75A devices using a 5.5mm × 2.5mm DC barrel connector
Replacement & Maintenance
A failing power adapter may cause symptoms such as device shutdowns, intermittent operation, power indicator failure, or unstable connectivity. Replacing the adapter with the correct voltage, current rating, polarity, and connector size can help restore normal equipment operation without replacing the entire device.
FAQ
Can this replace Motorola MT20-21120-A04F P/N 503913-007?
Yes. This adapter is designed as a compatible replacement for Motorola MT20-21120-A04F and P/N 503913-007 when the device requires 12V 0.75A power input with a matching 5.5mm × 2.5mm connector.
What is the output specification of this adapter?
The adapter provides 12V DC output at 0.75A (750mA), with a maximum power output of approximately 9W.
How do I verify compatibility before ordering?
Check your original adapter label and confirm the output voltage, current, polarity, and connector dimensions match before purchase.
What devices commonly use this adapter?
This adapter is commonly associated with compatible Motorola cable modems, digital receivers, and communication equipment requiring a 12V low-power external adapter.
