Yifang Digital Technology 728SF MP3 Player with FM Transmitter User Manual
Shenzhen Yifang Digital Technology Co., Ltd. MP3 Player with FM Transmitter
User Manual

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Cautions 
1.  Do not subject the device to severe impact or drop it from high position. 
2.  Do not use the player in extreme hot or cold, dusty or damp field. Do not expose it to 
direct sunshine. 
3.  Back up the data frequently in case of accident data loss. 
4.  Avoid using the player in strong magnetic field. 
5.  Keep the device away from water or other liquids. In the event that water or other 
liquids enter the device, power off the product immediately, take out the battery and 
clean the device. 
6.  Do not use chemical solution to clean the device in order to avoid corrosion. Clean it 
with a dry cloth. 
7.  We are not responsible for the damages or lost data caused by malfunction, misusing, 
repairing the device or battery replacement. 
8.  Do not attempt to disassemble, repair or modify the product, or it will be out of 
guarantee. 
9.  The design of the player or actual display may be different from what is shown in this 
manual. It should be subject to the actual display or design. 
FCC NOTICE 
1.  This device complies with Part 15 of the FCC Rules. 
Operation is subject to the following two conditions: 
(1) This device may not cause harmful interference, and 
(2) This device must accept any interference received, including 
interference that may cause undesired operation. 
2. Changes or modifications not expressly approved by the party 
responsible for compliance could void the user’s authority to 
operate the equipment. 

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1 Key Features 
    MP3&WMA Playback 
Play audio files in the format of MP3 or WMA. 
Navigation Function 
You can use the navigation function to search for and play the specified folder or track. 
Voice Recording 
Record voice as WAV file and playback the recorded content in excellent audio quality. 
FM Transmitter 
Transmit the audio signal from the MP3 player to the FM radio. You can receive the audio 
signal through the FM radio.   
Removable Storage Device 
Provides high-speed USB interface for you to copy files from or to the player. 
Lyric Display 
Display lyric of the current track during playback. 
2 System Requirements 
O  Hardware: IBM PC & Compatible PC, Notebook with USB interface 
O  Operating System: Windows98/SE, Windows Me, Windows2000/XP 
3 Package Content 
Please check the package for the following items. If any one of them is missing, please 
contact the vendor: 
O Main Unit 
O Stereo earphone 
O USB cable 
O Neck Strap 
O  AAA –size Alkaline Battery 
O User Manual 
O Driver CD 
4 Before Using 
4.1  Connect to the PC and download audio files 
For Windows 98/SE, you are required to install the included driver before connection. For 
detail information about driver installation, see the “Driver Installation” section.   
The MP3 player is a plug & play device under WIN2000/XP/ME OS. You don’t need to 
install the driver. Just connect the player to the PC and download audio files following 
these steps: 
(1)  Plug the larger end of the USB cable to the USB port of the PC, and plug the smaller 

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end to the USB port of the player. 
(2) Double click “My Computer” on the desktop, you see a removable disk which 
represents the player. Just copy the files from the PC to the removable disk. 
4.2  Removing the player from the PC safely 
For Windows2000/XP: 
(1)  Left click the    icon at the right hand corner of the taskbar.   
(2)  Click the pop-up mini-window with message of “Stop the USB Mass Storage Device – 
Drive (X)”. 
(3)  When you see the following prompt, pull out the MP3 player. 
For Win98, please make sure the data transfer is completed before unplugging the MP3 
player.  
4.3 Installing Battery 
(1)  Press on the battery cover and slide it off in the direction of the arrow. 
(2)  Insert one AAA - size battery. 
(3)  Close the battery cover. 
5 LCD Indication 
              Remark: ID3 Information includes track title, artist, album, lyric etc. 
6 Basic Operations 
Function Operation 
Power On/Off  Press and hold the    key until you see prompt on the display. 
Play Press the  key to play track. 
Pause  During playback, press the   key to pause. 
Stop  During playback, press and hold the   for a while to stop the 
playback and return to the beginning of current track. 
Adjust Volume  Press the V+ key to increase the volume.   
Press the V- key to decrease the volume.   
Play the previous 
track 
Turn the Control Wheel leftwards. 
Play the next track  Turn the Control Wheel rightwards. 
Fast Forward  Turn the Control Wheel to the right and hold it. 

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Rewind  Turn the Control Wheel to the left and hold it. 
Lock/Unlock keys  Push the   switch to the locked position to lock keys against 
being pressed accidentally.   
Push the    switch to the unlocked position to enable all keys. 
Select Mode  Music Mode –   
Press and hold the Control Wheel key to enter the main menu, 
select “Music” by turning the Control Wheel and then press the 
Control Wheel confirm. 
Voice Mode –   
Press and hold the Control Wheel to enter the main menu, select 
“Voice” by turning the Control Wheel and then press the Control 
Wheel to confirm. 
7 Advanced Features 
O Using the Menu 
Press and hold the Control Wheel to enter the main menu. 
Turn the Control Wheel leftwards or rightwards to select the menu item and press the 
Control Wheel to confirm the selected item. 
Press the   key to return to the previous menu level. Or, do not press any key it will 
return automatically in a few seconds. 
To exit from the menu mode, on the main menu, select “Return” and press the 
Control Wheel to confirm. Or, do not press any key, it will exit automatically in a few 
seconds. 
O Using the Navigation Function 
In the music or voice mode, press and hold the Control Wheel to enter the main 
menu, select the “Folder” item and press the Control Wheel to enter the folder 
navigation mode. 
To navigate through the folders: 
(1) Turn the Control Wheel leftwards or rightwards to select folder. 
(2) Press the Control Wheel to enter the selected folder.   
(3) Turn the Control Wheel to select track that you want to play.   
(4) Press the   key to play the selected track. 
(5) Press the Control Wheel to close the current folder. When you reach the root 
directory, you can press the   key to exit from the navigation mode and return 
to the main menu. 
To delete folder or track: 
(1)  In the navigation mode, select the folder or track that you want to delete. 
(2) Press the A-B key to delete it. 
(3) Turn the Control Wheel to select the “Yes” option and press the A-B key again to 
confirm deletion. 
Note: You can only delete empty folder.   
O A-B Repeat 
To repeat specified section of the current track,   

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(1) Press the A-B key during playback to select the start point of the repeat. At the 
top of the LCD screen shows “A-”. 
(2) Press the A-B  key again at the desired point to specify the end point of the 
repeat. At the top of the screen,“A-B”displays instead. The section between the 
start point and the end point begins to be played repeatedly. 
(3) Press the A-B key shortly to stop A-B repeat. 
O Select Play Mode 
You can switch between the following five play modes: 
Normal –Play all tracks in order and stop after playing all 
Repeat One –Keep repeating the current track 
Repeat All –Play all tracks in order and repeat 
Shuffle –Play all tracks randomly and stop after playing all 
Rep Shuffle –Keep repeating all tracks randomly 
To select the play mode: 
(1) In the Music or Voice mode, press Control Wheel shortly to show the 
submenus. 
(2) Select the “Repeat” item and press the Control Wheel to show the provided 
options. 
(3)  Select the desired mode option and press the Control Wheel to confirm. 
O Switch EQ Mode 
You can play the tracks in different sound effect. The device provides 6 EQ modes: 
Normal, Rock, Jazz, Classic, Pop and Bass. 
To set the EQ mode: 
(1) In the Music or Voice mode, press Control Wheel shortly to show the 
submenus. 
(2)  Select the “Equalizer” item and press the Control Wheel to show the provided 
options. 
(3)  Select the desired mode option and press the Control Wheel to confirm. 
O Preview Tracks 
    You can preview all tracks on the current play list before listening. In the preview 
mode, the player plays the first 10 seconds of every track. 
In the Music or Voice mode, press the Control Wheel shortly to show the submenus, 
select “Preview” and then press the Control Wheel to start preview. To end the 
preview, press the Control Wheel again. 
O Delete Single Track 
(1)  In the Music or Voice mode, turn the Control Wheel leftwards or rightwards to 
select the track that you want to delete. 
(2) Press the Control Wheel shortly to show the submenus.   
(3)  Select the “Delete” item and press the    key to confirm deletion. 
O Display Lyric 
To display the lyric during playback, you need to download a lyric file with the same 
name as the current track title to the player. The extension name for the lyric file is 
“.lrc”, you can download it from the related website.  

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8 Voice Recording 
O Record 
(1)  In the Music or Voice mode, press and hold the A-B key for a few seconds until 
you see the following recording screen. 
(2)  Speak into the built-in microphone. 
(3)  To stop recording, press the A-B key again. A voice file named as V00Y. WAV 
(where Y is the sequence number) is created. Now, you can press the   key to 
play the voice file that you just recorded. 
O Play Voice File 
(1)  On the main menu, select the “Voice” item to enter the Voice mode.   
(2)  Select the file that you want to play and press the   key to play it. 
Alternatively, you can enter the navigation mode, open the Voice folder and select the 
voice file that you want play.   
9 FM Transmitter 
FM transmitter enables you to transmit the audio signal from the MP3 player to the 
optional FM radio. You can use the FM radio to tune in the audio files being played on the 
MP3 player. 
Usage: 
(1) On the main menu, select the “FM Transmit” item 
and press the Control Wheel to confirm. 
(2) Turn the Control Wheel to select the FM frequency 
that receives the transmitted audio signal. 
(3)  Open the FM radio and tune to the frequency that 
you set in the step (2) above. Then you can listen in 
the music being played on the MP3 player. 
10 Customizing Settings 
On the main menu, select the “Settings” item and press the   key to enter the system 
settings mode.   
O Set backlight time 
On the main menu, select “Backlight” and press the Control Wheel to confirm. 
Select among the four options: 5 Secs, 10 Secs, Always on, Disable by turning the 
Control Wheel and then press the Control Wheel to confirm your selection. 

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According to this setting, when you press any key, the backlight will be on for the set time. 
O LCD Contrast setting 
(1)  In the “Settings” menu, select “Contrast” and press the Control Wheel to confirm. 
(2) Turn the Control Wheel to adjust the contrast level and then press the Control 
Wheel to confirm your settings. 
O Set the standby time 
On the main menu, select “Shutdown” and press the Control Wheel to confirm. 
Select one option from “1 Mins”, “2 Mins”, “5 Mins”, “10 Mins” and “Disable” and then 
press the Control Wheel to confirm your selection. 
According to this setting, the player will be turned off automatically when it is idle for 
selected time. 
O Set the timer 
On the main menu, select “Play Time” and press the Control Wheel to confirm. 
Select one option from “30mins”, “60mins”, “90mins”, “120mins" and “Always On”, and 
then press the Control Wheel to confirm your selection.   
According to this setting, the player will be turned off automatically when the set playing 
time is elapsed. 
O View memory state 
In the “Setting” menu, turn the Control Wheel to select “Memory”, and then press the 
Control Wheel see total capacity and free space of the internal memory. 
O Set Display Language 
On the “Setting” menu, select “Language” and press the Control Wheel to confirm. 
Select one language by turning the Control Wheel and then press the Control Wheel to 
confirm your selection. 
11 Driver Installation 
For Windows 98/SE, you are required to install the driver first before connecting it to the 
computer. 
(1) Insert the driver CD into the CD-ROM 
and execute the Setup.htm file on it. Click 
the player picture with correct model on 
the following pane. 
(2) Select “Run this program from its 
current location” in order to execute 
Setup.exe program at once, and 
then click “OK” to continue. 
(3) Click “Yes” on the following dialogue to 
start installation. 
(4) The installation progress starts. 

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Tip: For WIN2000 or WINXP, it is recommended to install the driver also so that you can 
upgrade, initialize or recover the system. 
(5) Click “Next” to continue.  (6) Click “Yes” to accept the license
agreement. 
(7) Click “Browse” to specify the directory 
where the driver is installed, or use the 
default destination, and click “Next” to 
continue. 
(8) Click “Next” to continue. 
(10) Click “Finish” to finish the 
installation and restart the computer. 
(9) The system executes the requested 
operations. 

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12 Firmware Upgrade 
To get the latest version of the firmware, 
(1)  Install the enclosed driver first. 
(2)  Connect the player to the PC. 
(3) Click “Start” → “Program” → EMXXX Digital Audio Player, and select “Firmware 
Update”.(Note: EM728SF is the player model) 
(4)  You are guided to the following upgrade dialogue. If “Format Date Area” is selected,
all files stored in the player will be erased. 
(5)  Press the “Start” button to start upgrading. 
Note: Firmware upgrade process will format the device. Please backup your important 
data before upgrading. 
13 Troubleshooting 
Problem Possible Cause  Solution 
The LCD displays 
nothing when the Play 
key is pressed. 
1.  No battery or battery is too 
low. 
2.  The keys are locked. 
1. Install or replace the 
battery. 
2.  Unlock the Hold switch. 
The player cannot be 
powered on even the 
battery is replaced. 
FAT table in the flash memory 
may have errors in the case of 
strong magnet, static, and 
incorrect disconnection.    
Upgrade the firmware 
Press the Play key after 
turning on, while the 
player has no response. 
The keys are locked by Hold 
switch 
Slide the Hold switch to the 
unlocked position. 
No sound when playing 
music or voice file. 
1.  The volume is too low. 
2.  There are problems with the 
audio file. 
1.  Adjust the volume. 
2.  Delete the file or play oth
files.  

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The player cannot be 
connected to the PC. 
1.  The driver is not installed or 
destroyed. 
2.  The USB interface is not 
supported by PC’s 
motherboard. 
1. Install or reinstall the 
driver shipped with the 
player. 
2.  Update or replace the 
PC’s motherboard. 
The displayed time is 
changing constantly. 
The bit rate of the MP3 file is 
changing during playback. 
Try to use fixed bit rate to 
compress the MP3 file. 
The PC has error when 
you plug and unplug the 
player. 
The player is disconnected from 
the PC abruptly while 
transferring files. 
Do not disconnect the player 
from the PC when 
transferring files. 
Total memory displayed 
on the player is not in 
accordance with the 
marked amount.     
Part of memory is used to store 
programs and display 
characters. 
Some of MP3 files 
cannot be played 
properly.  
The MP3 file is compressed by a 
standard, such as MPEG I Layer 
1 or Layer 2 that the player does 
not support.   
1.Delete the unsupported 
MP3 files. 
2.Use MPEG I Layer 3 
standard to compress the 
unsupported MP3 files. 
14 Technical Specifications 
Item Specification 
Capacity 16MB/32MB/64MB/128MB/256MB/512MB/1GB 
Battery Type  AAA-size alkaline or chargeable Lithium Battery 
Battery Life  6-10 Hours 
LCD  128X32 Pixel,White EL Backlight 
Earphone Power  5mW+5mW 
Output Frequency  20HZ-20KHZ 
Record Bit Rate  8KHz 
Audio File Format  MP3(MPEG 1/2/2.5 layer 3),WMA 
Record Format  WAV 
EQ Mode  Normal, Classic, Jazz, Pop, Rock, Bass 
SNR  >90dB 
Supported Languages  Simplified Chinese, Traditional Chinese and English 
USB Port  USB2.0 
Operational Temperature  0℃ ~ +55℃ 
Storage Temperature  0℃  ~  +55℃ 
Operational Relative Humidity *  20% ~ 90% 
Storage Relative Humidity *  20% ~ 93% 
15 Notice 
O  Plug & Play is only available for WIN2000/XP. It is not supported by WIN98 and 

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WIN98SE under which a driver needed to be installed. 
O  Push the Hold switch to the unlocked position to enable all keys before operation. 
O  Please replace the battery immediately when the display indicates low battery, or the 
device will be powered off automatically. 
O  Please unplug the player properly to avoid data losing.   
O  The transfer rate displayed on the PC may be different depending on the operating 
system. Exact transfer rate should be subject to the player's indication. 
O  When the recorded voice file is too large, it is normal that the response of the device 
may be slow.