Finally I found someone who manage to hack huawei E220 hsdpa modem antenna. He just made a simple modification on the internal antenna. Solder it with the SMA to N-Type pigtail Connector. The previous e220 antenna mod suggest that we have to use the RG174 and matching N-Type antenna connector. Since it is very rare to get. So the best is just soldering the internal antenna part. Some pictures [Sources : http://www.m0mcx.co.uk ]
