PCI Wifi Card Antenna replacement

[Rad3on]

Hello.
I believe my TL-WN851N PCI Adapter's antennas are damaged, as I get incredibly variable speeds and pings (I'm talking about 200ms+ pings when it should be 6ms, for example) when I play around with them. It just seems impossible to get minimally stable speeds and pings (I know wifi is pretty variable, but still, this is too much).

It has 2x2db antennas. I'm thinking about buying an extended antenna, but I can't decide between the TL-ANT2405C (5db) and the TL-ANT2408C (8db). I'd be removing both the old antennas, and connect just one of these. Would the 8db model be better as it would compensate the other empty antenna slot, or something?

Thanks

 

[kanewolf]

If you only replace one antenna, then you will cut the available bandwidth of the card in half. Both antennas are required to achieve the 300Mbit advertized speed. The gain (5db, 8db) of the antenna is offset somewhat by the loss of signal in the coax. But you gain the ability to position the antenna(s) better because of the coax. The best solution would be to replace BOTH antennas. What about purchasing a multi-antenna desktop that you could connect to both radios?