Introducción
This manual provides detailed instructions for the setup, operation, and maintenance of your MARATHON CL030025 Jumbo Atomic Wall Clock. This clock features automatic time synchronization, indoor temperature display, and a clear, large digital readout, ensuring accurate timekeeping and environmental monitoring.
Características principales
- Atomic Self-Adjusting Time: Automatically picks up time calibration signals for precise timekeeping.
- Jumbo Display: Large 17-inch display offers visibility from up to 30 feet, showing time, date, and temperature at a glance.
- NIST Signal Reception: Receives its controlling radio signal from the National Institute of Standards and Technology (NIST) in Boulder, Colorado.
- Pantalla de temperatura interior: Shows indoor temperature in either Celsius or Fahrenheit.
- Comprehensive Calendar: Displays the month, date, and day of the week.
Contenido del paquete
- 1 x MARATHON CL030025 Jumbo Atomic Wall Clock
- 3 pilas C
Producto terminadoview
Familiarize yourself with the clock's components and display layout.

Figura 1: Frente view of the clock, showing the large digital display for time, date, day, and indoor temperature. The atomic signal indicator and PM indicator are also visible.

Figura 2: Atrás view of the clock, illustrating the battery compartment and control buttons for setting time, date, and other functions.
Configuración
1. Instalación de la batería
- Abra la tapa del compartimiento de la batería en la parte posterior del reloj.
- Insert three (3) C batteries, ensuring correct polarity (+ and -) as indicated inside the compartment.
- Cierre bien la tapa del compartimento de la batería.
2. Initial Power-On and Atomic Time Synchronization
Upon battery installation, the clock will automatically attempt to synchronize with the NIST atomic time signal.
- Place the clock near a window, ideally facing Boulder, Colorado, for optimal signal reception. Avoid placing it near electronic devices that may cause interference.
- The signal reception icon (a radio tower with waves) will flash during synchronization.
- Once synchronized, the icon will become solid, and the clock will display the correct time, date, and day. This process may take several minutes to a few hours, depending on signal strength and environmental conditions.
- If the clock does not synchronize within 24 hours, try repositioning it or manually setting the time.
3. Selección de zona horaria
The clock supports 6 time zones. To select your time zone:
- Locate the "TIME ZONE" button on the back of the clock.
- Press the "TIME ZONE" button repeatedly to cycle through the available time zones (e.g., PST, MST, CST, EST, AST, NST).
- The selected time zone will be displayed on the screen.
4. Selección de unidad de temperatura
To switch between Celsius and Fahrenheit for the indoor temperature display:
- Locate the "C/F" button on the back of the clock.
- Press the "C/F" button to toggle between Celsius (°C) and Fahrenheit (°F).
5. Manual Time Setting (If Atomic Signal is Unavailable)
If atomic synchronization is consistently unsuccessful, you can manually set the time and date.
- Locate the "SET" button on the back of the clock. Press and hold it until the time display begins to flash.
- Use the "UP" or "DOWN" buttons (usually located near the SET button) to adjust the flashing digit (hour). Press "SET" to confirm and move to the next setting.
- Repita para minutos, año, mes y fecha.
- Press "SET" one last time to exit manual setting mode.
Instrucciones de funcionamiento
Lectura de la pantalla
La gran pantalla LCD muestra la siguiente información:
- Tiempo: Hours, minutes, and seconds (or PM indicator).
- Fecha: Mes y día.
- Día de la semana: Abbreviated day name.
- Temperatura interior: Current temperature in your selected unit (°C or °F).
- Indicador de señal atómica: Shows if the clock is receiving the atomic time signal.
Horario de verano (DST)
The clock automatically adjusts for Daylight Saving Time based on the atomic signal. No manual intervention is required for DST changes in regions that observe it.
Mantenimiento
Reemplazo de batería
When the display dims or becomes erratic, it is time to replace the batteries. The clock requires three (3) C batteries.
- Retire las pilas viejas del compartimento.
- Insert new C batteries, ensuring correct polarity.
- The clock will re-initiate the atomic time synchronization process upon battery insertion.
Limpieza
Wipe the clock's surface with a soft, dry cloth. Do not use abrasive cleaners or chemicals, as they may damage the display or casing.
Solución de problemas
- Sin pantalla o pantalla tenue: Verifique la polaridad de las baterías. Reemplácelas si tienen poca carga o están agotadas.
- Clock Not Synchronizing with Atomic Signal:
- Ensure the clock is placed near a window, away from electronic interference (e.g., TVs, computers, microwaves).
- Try repositioning the clock to a different location or orientation.
- Allow up to 24 hours for initial synchronization, as signal strength varies.
- If atomic synchronization is consistently unsuccessful, manually set the time and date as described in the Setup section.
- Hora/fecha incorrecta:
- Verify the correct time zone is selected using the "TIME ZONE" button.
- Check if the atomic signal indicator is solid. If not, refer to atomic signal troubleshooting.
- If manually set, re-enter the correct time and date.
- Temperature Reading Appears Incorrect: Ensure the clock is not exposed to direct sunlight, drafts, or heat sources that could affect the internal sensor's accuracy.
Presupuesto

Figure 3: Product dimensions of the MARATHON CL030025 Jumbo Atomic Wall Clock.
| Característica | Detalle |
|---|---|
| Marca | MARATHON |
| Modelo | CL030025 |
| Tipo de pantalla | Digital |
| Fuente de poder | Funciona con pilas |
| Pilas necesarias | 3 pilas C (incluidas) |
| Duración de la batería (promedio) | 1.5 años |
| Material | High Impact plastic |
| Tipo de montaje | Montaje en pared |
| Dimensiones del producto | 42 x 4.4 x 27 cm (16.5 x 1.7 x 10.6 pulgadas) |
| Peso | 1.15 kilogramos |
| Características especiales | Calendar Display, Indoor Temperature, Atomic Time Synchronization |
Información de garantía
MARATHON products are designed for reliability and quality. For specific warranty details, terms, and conditions applicable to your CL030025 Jumbo Atomic Wall Clock, please refer to the warranty card included with your product packaging or visit the official MARATHON websitio para obtener la información más actualizada.
Atención al cliente
If you encounter any issues, have questions not covered in this manual, or require further assistance with your MARATHON CL030025 clock, please contact MARATHON customer support. Contact information can typically be found on the product packaging, the official MARATHON websitio, o a través de su minorista.





