Extech CTH10A Operating Manual

User's Guide

Model CTH10

RADIO CONTROLLED CLOCK
with TEMPERATURE & HUMIDITY

GETTING STARTED

1. Remove the battery door by releasing the battery cover latch.

2. Insert four new AA size batteries as per indication marked on the battery
compartment.

3. Once the batteries are inserted, all the segments of the LCD will sho w
br i efl y b e f o r e en t e r i n g th e r a di o controlled time reception mode.

4. The RC Cl o ck wil l au to ma t ic al l y st a rt sc an ni n g fo r the radio controlled
time signal after 10 seconds.

5. The default time zone is Pacific zone. If you are in this time zone,
changing is not required. Otherwise, change to the correct time zone (Refer
to ‘Select the Time Zone’.)

: If there is no display on the LCD after inserting the battery, replace with four

Note

new batteries or press RESET key by u sin g a m et al w ire . I n so me c as es,
you may not receive a signal immediately. Due to atmospheric
disturbances, the best reception o ften occurs during night time.

FUNCTION KEYS

1. RESET: In case of mal-

2. MODE: Switch between Normal

3. SET: In editing mode, step the setting items.

4. ADJUST: In normal time mode, toggle between Date & Month and Year

5. °C/°F: Press it once to toggle between °C and °F format. Press

6. YEAR: In normal time mode, toggle between Date & Month and year display.

7. SNOOZE: Stop the current RC reception or stop the alarm sound during its

DISPLAYS SYMBOLS

Normal Time Mode

1. Time

2. Month

3. Date

4. Day of the week

5. Temperature

6. Humidity

7. Signal Strength Indicator

8. Daylight Savings Time (DST)

9. Time zone map

function after insert
of battery, use a pin to
press the RESET key
to restart the clock.

Time Mode and Alarm
Time Mode.

display. In normal time setting mode, change the setting value. In
Alarm time mode, switch ALARM/SNOOZE function ON/OFF.

and hold it for 3 seconds to receive the signal for reception
testing.

activation.

SELECT THE TIME ZONE

Make sure the time zone is set to appropriate location. The default time zone is
Pacific zone. If your location is not the Pacific zone, do the following:

1. In the normal time mode, press the MODE key to enter the alarm time mode.

2. Press the SET key to select the proper time zone. P=Pacific, M=Mountain,
C=Central, E=Eastern

DAYLIGHT SAVINGS TIME (DST)

The clock has been programmed to automatically switch when daylight savings
time is in effect. Your clock will show ‘DST’ during the summer.

SIGNAL STRENGTH INDICATOR

The signal indicator displays signal strength in 3 levels. Wave segment flashing
means time signals are being received. The signal quality could be classified into
three types:

Poor Acceptable Excellent
If the RC clock receives signal successfully, a Sync-time symbol appears on LCD.

The unit has already received the time signal. Otherwise, the signal strength
symbol will disappear from the LCD display.

Note:

1. You may use the RECEIVE button to receive the time signal manually. Be
caution of using t he RECEIV E mo de. The receive mode will be off
automatically after 6-12 minutes. Receive mode consumes more battery
power and reduces battery life.

2. In an environment with radio frequency interference, the unit may not maintain
the communication link a nd will resume to normal when interference stops.

3. P re ssing SNOO ZE key fo r 8 secon ds can st op th e curr ent RC reception.

MANUALLY SETTING THE TIME AND DATE

If the clock does not receive the time signal successfully, you can set the time
manually. As soon as the transmitter is received again, the clock will
automatically synchronize with the received time.

1. Press and hold “SET ” k e y fo r 2 s e co nds u ntil HOUR dig it flashes.

2. Press “ ADJUST” key to increase the value of t he flashing digit.

3. Press “SET” key again to step the setting items.
The sequence is: Hour > Minute > Second >12/24 HR > Month > Date > Year >
Day Language

4. Press the ADJ key to select the day language: GB=English, FR=French,
DE=German, ES=Spanish, IT=Italian

5 Press “MODE” key to exit the setting mode.

Alarm Time Mode

1. Alarm time

2. Alarm mode

3. Snooze icon

4. Alarm icon

SETTING THE ALARM

1. In the Normal Time Display, press “MODE” key to enter the Alarm Time
Mode.

2. Hold “SET” key for 2 seconds until HOUR digit flashes.

3. Press “ADJUST” key to increase the alarm hour value.

4. Repeat the above operation to set the alarm minut e.

5. Press “MODE” key to exit the setting mode.

USING THE ALARM AND SNOOZE FUNCTION

1. Set the Alarm time as described in the previous section.

2. Activate the Alarm by pressing the “ADJUST” key so that the bell icon “
appears.

3. Activate the Snooze by pressing the “ADJUST” key so that the s nooze icon
“Zz” appears.

4. T o de-acti vate the a larm and snoo ze fun ction, pr ess the “ADJUST” key
until both icons disappear.

Note:

When the snooze function is activated, the alarm will automatically start again
after 4 minutes, total 4 times. It won’t sound again until the next day.The
alarm duration is 60 seconds.

BATTERY REPLACEMENT

When the LCD becomes dim, re pla ce wit h f our new A A size batteries at once.
Pay attention to the battery polarity.

Note: Attention! Please dispose of used unit and batteries in an
ecologically safe manner.

IMPORTANT

For best reception, please read the following instructions:

1. This sophisticated instrument will automatically receive the time signal
transmits from the American Atomic Clock transmitter.

2. It is strongly recommended to start this clock at night and allow the clock to
receive the signal automatically overnight.

3. Always place the unit away from interfering sources such as TV set,
computer, etc.

4. Av oid pla cing t he unit on or next to met al surf aces .

5. Closed area such as airport, basement, tower block, or factory is not
recommended.

6. Do not start reception while moving in a vehicle or train.

SPECIFICATIONS

Measurement Range Accuracy
Temperature

Humidity

Storage Temperature: -4°F to 140°F (-20°C to 60°C)
Dimensions: 11.4x17x11.8” (29x43x30cm)
Weight: 2.75lb (1.25kg)

WARRANTY

EXTECH INSTRUMENTS CORPORATION warrants this instrument to be free of defects in parts
and workmanship for one year from date of shipment (a six month limited warranty applies to
sensors and cables). If it should become necessary to return the instrument for service during or
beyond the warranty period, contact the Customer Service Department at [phone] ext.
210 for authorization or visit our website www.extech.com
Authorization (RA) number must be issued before any product is returned to Extech. The sender
is responsible for shipping charges, freight, insurance and proper packaging to prevent damage
in transit. This warranty does not apply to defects resulting from action of t he user such as
misuse, improper wiring, operation outside of specification, improper maintenance or repair, or
unauthorized modification. Extech specifically disclaims any implied warranties or merchantability
or fitness for a specific purpose and will not be liable for any direct, indirect, incidental or
consequential damages. Extech's total liability is limited to repair or replacement of the product.
The warranty set forth above is inclusive and no other warranty, whether written or oral, is
expressed or implied.

23°F to 32°F (-5°C to 0°C) ±3°F (±1.5°C)
33°F to 86°F (1°C to 30°C) ±2°F (±1°C)
87°F to 122°F (31°C to 50°C) ±3°F (±1.5°C)
20% to 40% RH ±8% RH (@25°C)
41% to 70% RH ±6% RH (@25°C)
71% to 90% RH ±8% RH (@25°C)

for contact information. A Return

CTH10 V1.0 3/07

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