Digital Radio Three-Band FM AM SW Digital Clock Radio Kit with Acrylic Shell and Battery

Digital Radio Three-Band FM AM SW Digital Clock Radio Kit with Acrylic Shell and Battery

<1>: This product is the radio kit shown in the main picture. You need to assemble it yourself when you buy it back. You only need to prepare a screwdriver to complete the assembly without soldering electronic components.
<2>: There is no product circuit schematic diagram, PCB diagram, source program, installation and use instructions for this product purchased, all written on the details page, there is no other information.

Tips:
The role of the radio is to receive the signals emitted by broadcast stations, and the reception effect is different in different listening environments. When listening, it is recommended to stay as far away as possible from the disturbing household appliances and as close to the window and balcony as possible to adjust the antenna direction to achieve the best listening effect!

About the advantages and disadvantages of FM/MW/SW
FM (Frequency Modulation Broadcasting): (Radio wave signal: the amplitude remains unchanged, and the frequency is adjusted) The characteristics of listening to FM broadcast are low interference, clean sound, stereo (dual channel) programs can be received, and a wide range of audio; Disadvantages: Because the FM frequency band is mainly transmitted in a straight line and reflected by ground objects, the signal transmitted by a radio station has a short propagation distance and a small coverage area. Generally, only local stations can be listened to.

SW (Shortwave): The propagation of shortwave is mainly carried out by sky waves. It can be transmitted to a long distance with the help of sky waves with a small power. The sound quality is poor. The advantage is that the transmission distance is long, the coverage is large, and international broadcast programs can be heard. To

MW (medium wave): It can be transmitted through sky waves and ground waves. But Tianbo is very unstable. In the propagation process of sky waves, factors such as path attenuation, time delay, atmospheric noise, multipath effect, ionospheric fading, etc., will cause weakening and distortion of the signal and affect the effect of communication. Its characteristics are noisy, strong directivity, weak anti-interference ability, sound quality is acceptable, and the advantage is that it can receive far away wireless broadcasts in mono. Due to the influence of the ionosphere, there is basically no signal received during the day.

Function description and description of this product

1. Product introduction
This product is a high-sensitivity digital clock radio kit that integrates FM, AM, and SW three bands. It adopts a modular structure of splicing installation, which is very suitable for radio electronics enthusiasts, electronic DIY enthusiasts and primary and secondary school students to exercise their hands-on skills. The circuit modules are connected by connectors. The installation process can be completed only by preparing a screwdriver and referring to the installation diagram. A high-sensitivity digital radio can be assembled without using an electric soldering iron.


2. Product technical indicators
1. Frequency range
Frequency modulation (FM): 87-108MHz
Medium Wave (MW): 522-1620KHz
Shortwave (SW): 4.75-21.85MHz
2. Noise limit sensitivity
Frequency modulation (FM): 30dB ≤ 8dBu
Medium Wave (MW): 26dB ≤ 60dBu
Shortwave (SW): 26dB ≤ 32dB
5. Signal-to-noise ratio
Frequency modulation (FM): 98MHz ≥ 50dB
Medium Wave (MW): 1000KHz ≥ 40dB
6. Maximum output power
Headphones: ≥100mW*2
Speaker: 5W
7. Instantaneous maximum working current: ≤500mA
8. Maximum output distortion: ≤10%
9. Standby quiescent current in clock mode: ≤20uA (the lithium battery can stand by for 1 year when fully charged)
10. Power supply: 3.7V/1000mAH lithium battery
11. Size: 109x66x30mm (not including the protruding part of the antenna)
12. Overall weight: 166g


3. RADIO radio function description
1. Power switch (POWER)
Press the "POWER" button, the "ON" pattern will be displayed on the screen for 2 seconds, then the radio frequency and frequency unit will be displayed, and you can receive your favorite radio programs by adjusting other buttons. When this key is pressed again, the "OFF" pattern will be displayed on the screen for 2 seconds, and the radio will be turned off and it will return to the clock state standby.

2. Volume adjustment (VOL+/VOL-)
In the state of playing radio, short press the VOL+ key to increase the volume once, long press the VOL- key to increase continuously, short press the VOL- key to decrease the volume once, long press to decrease the volume continuously, and the adjustable range of volume is 00-31.

3. Frequency increasing/decreasing search channel (TUNING UP/DOWN)
In any band in the listening state, press the "UP" frequency to increase the search button and the "DOWN" frequency to decrease the search button to change the current radio frequency. Each short press is one radio frequency stepping unit. If you press and hold the button for more than 1 second before letting go, it will be a continuous stepping search mode, the radio frequency will increase or decrease rapidly, until the frequency of a radio program is found, it will automatically stop and play the sound, if you need to change it again For radio programs, you can repeat the above operations.

4. Sleep switch (LOCK_SLEEP)
Press the "LOCK_SLEEP" button for the first time, the sleep shutdown time and the "sleep icon" flash on the screen. The "90" number means that it will automatically shut down after 90 minutes of listening time, and the "sleep icon" indicates that the radio is in a sleep timer state. When the sleep timer "time number" on the display is flashing, you can repeatedly press the "sleep switch" button, the sleep time can be selected from: "90-60-45-30-15-10-OFF" minutes, when Select "OFF" to cancel the sleep timer function. During the sleep timer listening program, when you press the "POWER" button, you can turn off the radio function in advance and automatically return to the clock state standby.

In the radio mode, single press the button once, you can query the remaining time of the sleep timer, if you press it again, you can change the sleep timer parameters!
Note: Press and hold the "LOCK_SLEEP" button for more than 2 seconds. This button is the "key lock" function. The "lock" symbol is displayed on the screen and then let go. At this moment, the "lock" symbol flashes, indicating that all key functions have been locked (the key cannot be pressed) effect). If you need to unlock, you need to press and hold the "LOCK_SLEEP" button for more than 2 seconds until the "lock" symbol on the screen disappears before letting go, the lock is released, and other key functions return to normal use.

5. Clock setting (TIME)
<1>, press and hold the "TIME" button for 2 seconds, the screen displays "12/24" flashing and you can select the 12/24 hour format, the first time the battery is installed, the time display starts at 12:00 AM (morning). The clock setting must be set under the clock display interface. The clock setting button and the radio setting button can be used in combination. When the 12/24 hour format setting item is flashing, press the "TUNING_UP" button or the "TUNING_DOWN" button to switch the clock format. If there is no operation for 5 seconds, the system will automatically exit the current setting.
<2>, following the above steps, press the "TIME" button again, the 12:00 hour digit displayed on the screen is blinking continuously, press the "TUNING_UP" button or press the "TUNING_DOWN" button to change the hour and time. The hour changes rapidly after staying for more than 2 seconds. When there is no operation within 5 seconds, the system will automatically exit the current setting.
<3>. Press the "TIME" button for the third time following the above steps, the 00 minute time digit displayed on the screen is blinking continuously, press the "TUNING_UP" button or press the "TUNING_DOWN" button to change the minute time. The minutes change rapidly after staying for more than 2 seconds. When there is no operation within 5 seconds, the system will automatically exit the current setting.
<4>. Follow the step 4 above and press the "TIME" button to exit the current setting. Note: The current time is divided into 12-hour and 24-hour formats. The "AM" icon lights up to indicate the morning time, and the "PM" icon lights up to indicate 12 o'clock in the afternoon. This is the 12-hour format. If there is no AM/PM symbol, it is a 24-hour format!

6. Timing boot time setting (ALARM)
The ALARM timing power-on time setting must be set in the clock display mode. The ALARM timing power-on setting button is used in combination with the radio function button.
<1>. Press and hold the "ALARM" key for 2 seconds, the AL (alarm) hour time digit displayed on the screen will flash continuously, press the "TUNING_UP" key or "TUNING_DOWN" key to change the AL hour time. After pressing the button for more than 2 seconds, the AL hour time will change quickly. When there is no operation within 5 seconds, the system will automatically exit the current setting.
<2>, AL minutes setting refer to the previous operation. Press the "ALARM" key for the third time to exit the setting.

7. Timing start switch (ALARM_ON/OFF)

The ALARM_ON/OFF timing power-on switch setting must be set in the clock display mode. The LARM_ON/OFF timing power-on switch setting button is used in combination with the radio function button.

<1>, press and hold the "AL_ON/OFF" key for 2 seconds, the "alarm" icon is displayed on the screen, indicating that the AL function is turned on, press and hold for 2 seconds, the "alarm" icon disappears, indicating that the AL function is turned off.

8. Band selection (AM/FM)
After selecting one of the above two methods to turn on the listening function, press the band switch button once to select your favorite band program. The band change for each single press is: FM frequency modulation, AM amplitude modulation (medium wave), SW amplitude modulation (short wave) cycle.

9. Scan and store radio stations
In any band in the listening state, press and hold the "TIME" button for more than 2 seconds to scan and store the mode. The frequency of the current radio station will increase rapidly. Inside the memory chip. The display on the screen means that the first radio frequency is stored, and it means the second radio frequency is stored. When the number of stored radio stations is equal to or the radio frequency increases to the highest point (high end), the scanning storage state ends immediately, and the radio returns to the stored program The radio station may return to the lowest frequency (low end) state.

10. M+/M-storage and access

Long press the ALARM key for the "M-" function, long press the ALARM_ON/OFF key for the "M+" function.
In any band in the listening state, press the "M+" or "M-" button for storing and fetching channels, and the address number of the frequency storage will be incremented by one unit or decremented by one unit.
Bit address number to high (see the number of stored radio stations for the highest point). The user can quickly change programs by pressing the "M+" or "M-" button.
If you want to save the current radio frequency, press and hold the "M+" button or the "M-" button until the "PRE" symbol appears, and quickly press the "M+" or "M-" button during the flashing of the symbol, and choose whether you want to keep On the address.

Note: To use the M+/M- memory address number fetching function, you must first complete the scan of the relevant band to store the radio program or manually store the station to make sense, otherwise you can only press the fetch button to return to and then display the lowest radio frequency. .

If the AL function is turned on, when the real-time time and the AL time run to the same time, the radio playback function is automatically turned on, and the playback function is automatically turned off after 30 minutes of listening. This AL function can only listen to, and cannot operate the buttons. Once operated, it will exit this function.

There are three ways to start the radio playback. Since the AL function is turned on regularly and the radio function cannot be operated by keys, only the other two ways to start the radio function are introduced.


11. Function description of whip antenna
When listening to FM radio or shortwave SW radio program, you need to turn on the telescopic antenna. When you receive a radio program, slowly rotate the angle of the telescopic antenna by hand until the sound of the radio is clear and loud. For radio programs in different directions, the whip antenna needs to be rotated at different angles. By adjusting the angle of the antenna, the receiver can achieve the best reception effect. In addition, a whip antenna is not required to receive MW mid-wave band programs, it relies on a magnetic rod coil to receive signals. If you want better reception, you must turn the body of the unit to find the direction where the radio station is the loudest.