Hi All

I have a CTX100 where need to install one more ISDN card, there ARE already have 6 ISDN ports that's 3 Cards. Is there any way of installing another ISDN without getting another system. I heard you can piggy back a card on top of the ISDN card. If so what is the part number for it as I at lost to figure it out.

I am based in Ireland

Thanks Michael