If you aqquire an AT->PS2 adapter then you can use any ps/2 adapter on this keyboard adapter, the cable is very cheap , any pc store should have it.
anyway if not, this AT plug can use ALMost all old keyboards, but some wont work....
also an a4k keyboard will work (but then u need the AT->ps/2 cable) (atleast i did....)
the a3k keyboards are abit weird, i had probs with connecting it to my a1200..., same goes for a2k..., might just be defektive keyboards thou.
good luck...hope it helped.