QUOTE(chuahcs79 @ Nov 6 2011, 06:12 PM)
well in my case
i do have a 3G yagi antenna,. it didnt work that well for me in my area compare with the strainer or windsurfer,. and also end up i accidently rip offthe connector in my E1762modem too, ( same like Digilife )
i suspect that usb modem is either can't provide enough power gain to the yagi to perform, or usb modem is just plain dont work in my area due to 3G band 900Mhz ?
and end up i testing with phone,. easier and signal is end up stronger and so strong like most of the time is FULL,. also achieve the highest speed that i wanted and consistency is higher than usb modem i( in my area )..
so now i dont know what to do with my 3G yagi antenna

chuachcs79, usb 3G modem is equipped with higher transmission power than our normal wifi usb receiver. basically usb 3g modem can have around 200mW / 23dbm TX power, more than enough to run any high gain antenna. (lately P1 going to launch new a home desktop modem with around 500-600mW TX power, this should be a concern issue instead (too powerful), as this power level is normally for outdoor CPE or Bridge device for wifi project for e.g, if put indoor to use with elder folks, small children around is too hassle, don't know if MCMC would pass that device or not). (nor worth sacrify users' health in long term just for good signal for internet surfing purpose and for company profits)
so get rid of 3g usb modem wireless power matter, i think the issue should be lie in the what Maxis 3g band run in your and digilife area based on both feedback much alike (2100MHz + 900MHz or 900MHz alone?)
3G high gain yagi antenna are tuned to provide high gain for 2100MHz only, no dual or multi-bands, no high gain for other frequency.
If Maxis in your area cancelled tradisional 3G 2100MHz and swithced to 900MHz totally instead of running both, then that's the reason why you two experienced poor performance with dedicated 3G antenna for 2100MHz, bcoz no gain for 900MHz. (maxis/celcom do dual band at some major cities in peninsular beginning this year, rural and sabah / sarawak not affected)
and this also explained why digilife using that lower gain 10dbi dual-band panel which support 900MHz ~2100MHz can have higher signal result than dedicated 3G 18dbi yagi for 2100MHz. the mystery solved.
one easy to find out if dual band runs or what band(s) run in your area by maxis, get a 2100MHz supported only 3g modem (don't use dual band 3g modem or dual band phone) test at open space / outdoor, such as using huawei E1550 (borrow from digi users), if using that yield no signal or worst signal, then knowing 2100MHz not functioning there. need not keep changing 3G antenna to test and wonder why, all 2100MHz 3G antenna (omni or directional) will give same result.
** btw, soldering always has risk, no guarantee perfect job done ya. if modem somehow not functioning, can give it a try. if crc9 jack already completely ripped off, i think can try solder the cable to replace the crc9, better don't touch the internal antenna part, let the internal antenna there, once successful, can having back dual antenna system, just crc9 connector gone replaced with a rp-sma connector.
This post has been edited by coolstore: Nov 7 2011, 01:25 PM