The PT20C Weather Station Clock is a versatile device available in WWVB RCC/NO RCC versions, designed to provide comprehensive environmental monitoring and timekeeping functionalities. This user manual outlines its features, specifications, and operational procedures.

Function Description

The PT20C Weather Station Clock offers a wide array of functions, including:

Perpetual Calendar: Displays the date, day of the week, and moon phase.
RCC Function (RCC Version Only): Automatically receives time signals (WWVB) for accurate timekeeping and supports multiple US time zones (EST, CST, MST, PST).
Multi-time Zone Clock (WWVB Version Only): Supports US time zones.
Weekly Display: Supports 7 languages: English, German, Italian, French, Spanish, Dutch, and Danish.
Personalized Alarm Clock: Allows setting alarms for weekdays, weekends, or every day, with a snooze function.
Moon Phase Display: Automatically calculates and displays the moon phase based on the calendar (northern hemisphere image).
Weather Forecast: Provides weather predictions with various icons for sunny, partly cloudy, cloudy, rainy, thunder shower, snowy, and heavy snow.
Temperature and Humidity Measurement: Measures both indoor and outdoor temperature and humidity, supporting Celsius and Fahrenheit units.
Temperature Measurement Range:
- Receiver: -9.9°C to 50°C (14.2°F to 122°F). Displays "HH.H" for temperatures above 50°C and "LL.L" for temperatures below -9.9°C.
- Wireless Sensor: -40°C to 70°C (-40°F to 158°F). Displays "HH.H" for temperatures above 70°C and "LL.L" for temperatures below -40°C.
Humidity Measurement Range:
- Receiver and Sensor: 20-99%. Displays "HH" for humidity above 99% and "LL" for humidity below 20%.
Air Pressure Measurement: Range of 800-1100 hPa with an error range of ±2hPa. Supported units include hPa, mb, inHg, and mmHg.
Data Trend Display: Shows trends for indoor and outdoor temperature, humidity, and air pressure.
Max/Min Records: Records maximum and minimum temperature and humidity.
Dew Point Temperature: Calculates and displays dew point.
Frost Alarm: Alerts when channel 1 temperature is between -2°C and 3°C.
Temperature Alarm: Allows setting upper and lower limits for temperature alarms.
Heat Index: Calculates and displays the heat index, providing warnings for potential heat-related health risks.
Indoor Comfort Graded Expressions: Displays comfort levels based on indoor temperature and humidity (Comfortable: 40-69% RH, Dry: ≤39% RH, Wet: ≥70% RH).
Multi-Sensor Connectivity: The PT20C receiver can connect to up to 3 signal sensors simultaneously, displaying data from each in a carousel mode.
Low Battery Alarm: Alerts when batteries are low for both the receiver and sensors.
LCD Backlight: Provides illumination for easy viewing.

Important Technical Specifications

Power Supply:
- Receiver: 3 x AAA (LR03) batteries or DC 5V power input.
- Wireless Sensor: 2 x AAA (LR03) batteries.
Temperature Units: Celsius (°C) and Fahrenheit (°F).
Air Pressure Units: hPa, mb, inHg, mmHg.
Calendar Range: 2020-2099.
Alarm Duration: 2 minutes.
Snooze Duration: 5 minutes.
Maximum Alarms: 5.
Indoor Temperature Detection Cycle: 30 seconds.
Outdoor Temperature and Humidity Transmission Cycle:
- Channel 1: Every 93 seconds.
- Channel 2: Every 97 seconds.
- Channel 3: Every 101 seconds.
Temperature Error Range: ±1°C.
Humidity Error Range: ±5%.
RCC Receiving Time: Approximately 3-8 minutes.
Daily RCC Automatic Receiving Times: 1:03, 2:03, 3:03 (mandatory); 4:03, 5:03 (selection).

Usage Features

Initial Power-On/Reset: Upon power-on or reset, the device displays a full screen for 3 seconds with backlight on, emits a beep, and then shows real-time indoor temperature and humidity. It automatically enters RF signal receiving mode to connect to sensors and RCC search mode (for RCC versions).
Time Setting: Long press "TIME" for 2 seconds to enter time setting mode. Use "▲/RF" to advance and "▼/MEM" to go back. Settings are saved after 20 seconds of inactivity.
Alarm Setting: Long press "ALARM" to enter alarm setting mode. Set alarm time and repeat mode (Daily, Mon-Fri, Sat-Sun).
Outdoor Temperature Alarm Setting: Long press "ALERT" to set upper and lower temperature limits for outdoor alarms.
Backlight Control:
- With battery power: Backlight highlights for 30 seconds after power-on/reset or when touched.
- With power adapter: Backlight remains bright. Touch "SNOOZE/LIGHT" to switch between "strong," "weak," and "off" brightness levels.
RCC Functionality (RCC Version Only):
- Automatic reception after power-on/reset.
- Manual entry by long pressing "SNOOZE/LIGHT."
- Stop reception by long pressing "SNOOZE/LIGHT" during reception.
- RCC symbol flashes during reception and is continuously displayed upon successful reception.
RF Functionality:
- Automatic RF reception for 3 minutes after battery installation.
- Long press "▲/RF" in standard mode to clear outdoor channel data and re-receive signals.
Max/Min Temperature and Humidity: Long press "▼/MEM" to clear memory values. Memory values are also cleared daily at 0 o'clock.
Heat Index and Dew Point: Single press "HI/DP" to cycle between heat index and dew point display.

Maintenance Features

Battery Replacement: Replace AAA batteries in both the receiver and wireless sensors when the low battery alarm is displayed.
Signal Loss: If a sensor signal is lost for 60 minutes, the CH temperature display will show "--.-". The display will be restored once the signal is received again.
Alarm Exit: Press any key (except "SNOOZE/LIGHT" during an active alarm) to exit the alarm.
Setting Exit: Settings are automatically saved and exited after 20 seconds of inactivity in any setting mode.

PROTMEX PT20C - Weather Forecast Icons

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