Cheap chinese tablets come with cheap components obviously to keep production costs down. The wifi module used is no exception. Signal range is moderate to low that just moving to the next room, connection is dropped. Hence this mod.
I have opened the tablet in the past to reveal its components to address several issues. I tried soldering magnet wires as antenna to the module in full, half, and 1/4 of the wifi wavelength. While it increased the signal to around -10dBm (highest I got), the connection is still not reliable as I still encounter browser and download timeouts. In the future, I will solder-in a laptop antenna in hope that the wifi connection will be more robust. Or transplant a new wifi module with built-in bluetooth to get things going!
I have also played around with txpower in the build.prop as the wifi module gets hot after a while of internet activity. I assumed connection timeouts were caused by the module overheating. I have set it at 80 presently and gives me a good compromise on heat, signal strength and battery life. Iwconfig is not installed stock so I will show you that in another day.
For the meantime, I am using an external usb wifi adapter pictured below. I chose this because it is tiny and does not protrude much on the case. It is working wonderfully on the tablet. It shows a faint blue light showing it is turned on and blinks when there is wifi activity.
HOW TO USE
Turn off the wifi switch in Settings-Wifi. Then insert the usb wifi adapter in the usb host port. Then turn on. Voila! It works! Don't you just love the usb host (USBOTG) functionality of this tablet?
On stock Eken firmware, Realtek "drivers" are already incorporated so it should work out-of-the-box. No need for insmod-ing linux drivers. I have tried a Ralink based usb wifi adapter but unfortunately it shows no activity.
WHY IT WORKS
The built-in wifi module is behind the metal backplate of the lcd screen, effectively blocking and interfering with the signal. The proximity of the wifi module to the processor, ram, etc. chips and with no shielding exposes it to more electronic noise/interference.