Introduction
Welcome to your Timex Classic Digital 34mm Watch. This timepiece combines a timeless retro design with essential modern features, including a chronograph, alarm, and the signature INDIGLO night-light. This manual will guide you through the setup, operation, and care of your watch to ensure optimal performance and longevity.

Front view of the Timex Classic Digital 34mm Watch, showcasing its gold-tone finish and digital display.
Setup
Before using your watch, it is important to set the correct time, date, and configure any desired features.
1. Setting Time and Date
- Press the SET button (top left) once to enter time setting mode. The seconds will begin to flash.
- Press the MODE button (bottom left) to cycle through the settings: seconds, hours, minutes, month, date, day of the week.
- Use the START/STOP button (top right) to adjust the flashing value.
- Once all settings are correct, press the SET button again to exit setting mode.

Side view of the watch, highlighting the control buttons for setting and operation.
2. Setting the Alarm
- From the normal time display, press the MODE button until "ALARM" appears on the display.
- Press the SET button. The alarm hour will flash.
- Use the START/STOP button to adjust the alarm hour.
- Press MODE to select minutes, then use START/STOP to adjust.
- Press SET to confirm and exit alarm setting mode.
- To activate/deactivate the alarm, press the START/STOP button while in alarm mode. An alarm icon will appear when active.
3. Using 24-Hour (Military) Time Mode
Your watch supports both 12-hour (AM/PM) and 24-hour (military) time formats. To switch between modes, enter time setting mode (as described in "Setting Time and Date"), and when the hour is flashing, press the START/STOP button to toggle between 12-hour and 24-hour display.
Operating Instructions
1. Using the INDIGLO Night-Light
The INDIGLO night-light illuminates the watch display for easy viewing in low-light conditions. To activate, press and hold the INDIGLO button (bottom right). The light will remain on as long as the button is pressed.
2. Using the Chronograph (Stopwatch)
- From the normal time display, press the MODE button until "CHRONO" or "STOPWATCH" appears.
- Press the START/STOP button to start the chronograph.
- To record a split time, press the SPLIT/RESET button (bottom right) while the chronograph is running. The display will show the split time, while the chronograph continues to run in the background. Press SPLIT/RESET again to return to the running time.
- Press START/STOP to pause the chronograph.
- To reset the chronograph to zero, press SPLIT/RESET while the chronograph is paused.
3. Water Resistance
Your Timex watch is water resistant to 30 meters (100 feet). This means it is suitable for splashes, rain, or brief immersion in water. It is not recommended for swimming, diving, or showering, as prolonged water exposure or high-pressure water jets can compromise the water resistance seals.
Maintenance
1. Battery Replacement
The watch uses one Lithium Metal battery. When the display becomes dim or the functions stop working, it's time to replace the battery. Due to the specialized tools and procedures required to maintain water resistance, it is highly recommended to have the battery replaced by an authorized Timex service center or a professional watch repairer.

Rear view of the watch, showing the stainless steel back plate.
2. Cleaning Your Watch
To clean your watch, wipe it gently with a soft, damp cloth. Avoid using harsh chemicals, solvents, or abrasive cleaners, as these can damage the watch's finish or seals.
3. Band Care
The expansion band is designed for comfort and durability. To clean the band, you can gently stretch it and wipe between the links with a soft, damp cloth. Ensure it is completely dry before wearing. Avoid excessive stretching or bending that could damage the links.
Troubleshooting
- Display is Blank or Faint: This usually indicates a low battery. Refer to the "Battery Replacement" section for guidance.
- Buttons are Unresponsive: Try pressing the buttons firmly. If the issue persists, a battery replacement might be needed, or contact customer support.
- Time is Incorrect: Re-set the time and date as described in the "Setting Time and Date" section. Ensure the 12/24-hour mode is set correctly.
Specifications
| Model Number | T786779J |
| Case Diameter | 34mm (Resin) |
| Band Width | 18mm (Stainless Steel Expansion Band) |
| Movement Type | Quartz |
| Display Type | Digital (Green) |
| Water Resistance | 30 Meters (100 Feet) |
| Special Features | INDIGLO Night-Light, Chronograph, Alarm, Month/Day/Date Calendar, 24-Hour Mode |
| Battery Type | 1 Lithium Metal (included) |
| Item Weight | 1.6 ounces |
Product Videos
Timex Sizing Chart
This video provides a visual guide to Timex watch sizing, demonstrating how different case sizes appear on various wrist sizes.
Timex Men's T78677 Classic Digital Gold-Tone Stainless Steel Expansion Band Watch Overview
An official overview video showcasing the features and design of the Timex Classic Digital Gold-Tone Stainless Steel Expansion Band Watch.
Warranty and Support
Warranty Information
Your Timex watch is covered by a manufacturer's warranty. Please refer to the warranty card included with your purchase for specific terms, conditions, and duration. Keep your proof of purchase for warranty claims.
Customer Support
For further assistance, technical support, or service inquiries, please visit the official Timex website or contact their customer service department. Contact information can typically be found on the Timex website or in the packaging materials.