First Download this Openwrt image ( compile by khairilyazit & Ibnuasad )
-> openwrt-ar71xx-generic-tl-mr3420-V1-squashfs-factory.bin!
( http://www.mediafire.com/?2kfwsxglm54xucs#)

now follow all these step below with LAN CABLE CONNECTION ONLY:

- go to your browser login 192.168.1.1
- sign in
- go to system
- firmware upgrade
- click browse ( find the openwrt firmware u download just now )
- click upload
- wait for uploading firmware finish and it will auto reboot ( make sure dont power off the router when this period because it will brick the router )
- once update % finish, try to close your browser and clear your browser cache
- then login 192.168.1.1 ( you will see LuCI Gui interface )
- click login
- go to System
- go to Administration
- key in your new password ( For web Gui )
- re key in your same password again
- click save and apply
- go to Network
- click Edit on Wan ( 3G wan )
- select UMTS/GPRS/ED-VO protocol
- click switch protocol
- select UMTS/GPRS/ED-VO on protocol again
- Modem device ( zte mf680 = /dev/ttyUSB1 , E372 = /dev/ttyUSB0 <- last is zero )
- service type : select UMTS only or UMTS/GPRS
- Key in your ISP APN , ( Unet, Maxisbb, bbnet, celcom3g, u3g, my3g and so on )
- Go to ADvance setting
- Modem init time out: 5 ( key in )
- Use gateway Metric : 0
- Tick the box of : if uncheck, No default route is configure
- Use custom DNS server : 8.8.8.8 click the icon at the end
- second roll: 8.8.4.4
- LCP echo failed Threshold : 0
- LCP echo interval : 5
- Inactivity timeout: 0
- select Wifi
- click Edit
- select your wifi prefer channel 1~11
- enter your wifi name in ESSID
- go to Wireless security
- encryption : WPA2-PSK
- key : wifi password
- click save and apply
- then click enable to on your wifi ( if u need it )
- now go to System
- Reboot
- click Performs reboot
- plug in your Usb modem after
- wait for reboot finish and enjoy

It's under System > Scheduled Task.

Example command:
* * * * * /bin/ping -q -s 1 -c 60 8.8.8.8 & > /dev/null

That command will ping Google DNS 60 times every minute.

reboot and enjoy

APN just select from the choice,
if can;t find, u can set manually

Guys,

i just learn a new setting of the tl-mr3420 Router from this link -> Here

( Original credit is to P3wP3w in that forum )

- Go to your router web interface 192.168.1.1
- Login with your ID and Pass word
- Go to Bandwidth Control
- Tick the box of -> Enable Bandwidth Control
- Line Type : Tick Other
- Egress Bandwidth: put -> 100000 Kbps
- Ingress Bandwidth: put -> 100000 Kbps
- Click Save
- Go to System Tools
- Select Reboot
- Click the Reboot
- Click OK
Enjoy the Improvement of Max speed of your Modem with this router,.
You'll see the immediate different of speed, higher consistency, and better upload speed as well
Hope this helps you guys out,..

download -> Putty

run the putty

SSH to 192.168.1.1

enter

sign in username : root

sign in password : your LuCI GUI password ( remember when u type password nothing will appear on screen )

enter

keep in this command



enter

31,99 = RSSI : -51dBm

so meaning 31 = 100% signal

[*]Connect to your MR3420 via ssh protocol using Putty:-

Enter username (root) & password (you set earlier).
[*]Disconnect & reconnect your modem to MR3420
[*]In putty, type in:-

and press Enter
[*]Then navigate the "log" using Up & Down arrow buttons on your keyboard until you see something like this (you need to look for "USB device" or similar):-

It will give you idea which one you need to select in drop down menu.
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