Wifi adapter very low signal :(

Fellow Triskellonians, today, finally, after weeks of waiting for it to ship from Honga Konga, the wifi adapter for my new very old yet smooth old laptop I bought a month ago for 20 euros X_x, has arrived. As expected it works without the need for any kind of nasty blob but I have to sit a meter or max 2 from my router for it to work.
Strange thing is it stops to work at the very same distance (a meter and a half give or take) at which the default original adapter (which requires the blob) used to stop working during my previous testing.
The adapter is a full minipc atheros (very large adapter):

gnu@debian:~$ lspci -nnk | grep Network
06:05.0 Network controller [0280]: Qualcomm Atheros AR5416 Wireless Network Adapter [AR5008 802.11(a)bgn] [168c:0023] (rev 01)

My question is: does this have to do with the fact that the laptop is 10 years old, and will the external dongle from technoetic or thinkpenguin work decently with this dinosaur of mine? I really don't want to spend 40 euros for noff..
Does anyone here have any experience with old (2005/2006) laptops and wifi adapters/dongles?

Is there any setting in the router to fiddle with, in order to boost the stupid signal?

Any help, idea or tip is very welcome.