Zgrmbo Night Light Atomic Clock User Manual

1. Product Overview

The Zgrmbo Night Light Atomic Clock (Model ZG3566A) is a versatile digital clock designed for various indoor settings such as bedrooms, desks, and travel. It features an accurate atomic time calibration, automatic daylight saving time adjustment, and a built-in ambient light sensor for auto-dimming. Additionally, it provides indoor temperature and humidity readings, and offers dual alarm settings with a customizable snooze function.

Zgrmbo Night Light Atomic Clock front view displaying time, date, temperature, and humidity — Front view of the Zgrmbo Night Light Atomic Clock, showing its clear digital display with time, date, indoor temperature, and humidity.

2. Setup & Initial Use

2.1 Battery Installation

The clock is powered by 2 AAA batteries (not supplied). To install:

Open the battery compartment cover located on the back of the clock.
Insert two new AAA batteries, ensuring correct polarity (+/-).
Close the battery compartment cover securely.

Back view of Zgrmbo clock showing open battery compartment and stand — Rear view of the clock with the battery compartment open, indicating where to insert two AAA batteries (not included).

2.2 Atomic Time Synchronization

After battery installation, the clock will automatically attempt to retrieve the WWVB time calibration signal sent by NIST. This process ensures accurate time to the second and automatically adjusts for Daylight Saving Time (DST).

The clock will search for WWVB time airwave signals at 1:00 AM, 2:00 AM, and 3:00 AM each day to correct the time.
To ensure better reception, place the clock in an area with a good signal, such as near a window.
The clock supports 7 time zones: AST, EST, CST, MST, PST, AKT, HAT. Ensure you select the correct time zone before the clock calibrates.

Zgrmbo clock displaying atomic time synchronization feature with a map of US time zones — The atomic clock feature automatically calibrates the time signal. A map illustrates the 7 supported time zones across the USA.

3. Operating the Clock

3.1 Time Display & Format

The large LCD display shows the current time, date, day of the week, indoor temperature, and humidity. The time can be displayed in either 12-hour or 24-hour format.

3.2 Auto-Dimming & Night Light

The clock features a built-in ambient light sensor. In dark environments, it automatically triggers a soft night light to illuminate the display. You can manually control this feature:

Long press the top of the clock to turn the auto-dimming mode ON/OFF.
Short press the top of the clock to manually light up the clock display.

Comparison of Zgrmbo clock display in bright and dim light, showing auto-dimming feature — The clock's auto-dimming feature adjusts display brightness based on ambient light, ensuring readability day and night. Manual light-up is also available.

3.3 Alarm Clock with Snooze

The Zgrmbo clock includes two independent alarm settings. The alarm sound gradually increases in intensity over 120 seconds. The snooze function is customizable.

Set two distinct alarms for different needs (e.g., weekday and weekend).
The snooze duration can be set from 5 to 60 minutes.

Zgrmbo clock showing two alarm settings and snooze feature — The clock offers two customizable alarm settings and a flexible snooze function (5-60 minutes).

3.4 Temperature & Humidity Monitor

Keep track of your indoor environment with the integrated temperature and humidity sensors.

Temperature range: 14℉ to 122℉ (-9.9℃ to 50℃).
Humidity range: 20%RH to 95%RH.

3.5 Product Overview Video

Official product video demonstrating the Zgrmbo ZG3566A Digital Clock's features and battery operation.

4. Buttons and Controls

The control buttons are located on the back of the unit, allowing for various settings adjustments.

Up/Down Arrows: Navigate menus and adjust values.
Alarm Icon: Set and activate alarms.
Gear Icon (Settings): Access general settings for time, date, and other preferences.
°C/°F Button: Toggle between Celsius and Fahrenheit for temperature display.
Antenna Icon: Manually initiate atomic time synchronization.

5. Care & Maintenance

Clean the clock's surface with a soft, dry cloth. Avoid abrasive cleaners or solvents.
If the display becomes dim or unresponsive, replace the AAA batteries.
Do not expose the clock to extreme temperatures, direct sunlight, or high humidity.

6. Troubleshooting

Problem	Possible Cause	Solution
Clock not displaying time/powering on.	Batteries are dead or incorrectly inserted.	Replace batteries with new AAA batteries, ensuring correct polarity.
Atomic time not synchronizing.	Weak WWVB signal.	Move the clock closer to a window or to a different location with better signal reception. Allow several hours for synchronization.
Time resets randomly.	Interference or weak signal causing reset.	Ensure the clock is not near electronic devices that may cause interference. Try relocating the clock.
Display is too dim or too bright.	Auto-dimming setting or manual override.	Long press the top button to toggle auto-dimming. Short press to manually adjust brightness.

7. Technical Specifications

Feature	Specification
Brand	Zgrmbo
Model Number	ZG3566A
Display Type	Digital
Power Source	Battery Powered (2 x AAA, not included)
Product Dimensions	6.75"W x 5.5"H
Item Weight	13.4 ounces
Material	Acrylonitrile Butadiene Styrene (ABS)
Special Features	Atomic, Auto Dimmable, Temperature Display, Humidity, Snooze
Temperature Range	14℉ to 122℉ (-9.9℃ to 50℃)
Humidity Range	20%RH to 95%RH
Time Zones	7 (AST, EST, CST, MST, PST, AKT, HAT)

Zgrmbo clock with dimensions overlayed, showing 7 inches width and 5.5 inches height — Dimensions of the Zgrmbo Night Light Atomic Clock: 7 inches wide by 5.5 inches high.

8. Warranty & Support

For detailed information regarding product warranty and additional support, please refer to the official user manual provided by the manufacturer.

You can access the User Manual (PDF) here.

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Zgrmbo ZG3566A