Hi Trev,
I changed the original 320gb Humax drive for a 1tb, I fitted the 320gb in a caddy (Ext drive No1). I next bought another external 1tb (Ext drive No2) just to make sure we had plenty of capacity. A couple of weeks ago our 42" LCD went belly up so I bought a 46" LED from Currys, this new TV had pause and rewind (Freeview), so I bought another 1tb usb drive to try it out (I only wanted it to record Red Dwarf and a few things on Quest). It turned out to be almost useless as it only recorded what was on the screen at the time, useless, I gave up on that and now had a spare 1tb drive. I do not need another drive for the PC so thought I would add it to the Humax, hence my original question. Hope this answers your query.