Ok. You are right. I can call the phone from the pad fine. But calling the pad from the phone results in the busy situation. The problem is both devices are associated with the e mail address.
So here is the solution.
Use an alternate email address on the pad. If you have one, you are all set. If you do not, then goto google mail and set up a gmail account. It is free, and it never hurts to have ana alternate email address laying around. Once you have an alternate address
1. On the pad. Setting, face time, click on add e mail . Enter the new address. To get it to stick, you need to click add email again.
2. You will se the label 'email' changes to 'verifying'. Go to you new gmail, and respond to the verififcation e email that apple has just sent you. (They sent me the email within 1 minute)
Once you do this , the pad will answer face time calls to eith the original or the new e mail address.
3. On the phone. Go into contacts and find your own contact entry. Add the new email address.
4. Do not add the new email address on the face time 'receive' setting on the phone. If you do, you will end up back where you started.
So. When you call you phone from the pad, use the phone number. When you want to call the pad from the phone, use the alternate e mail address. When others call, ifmthey use the phone number, the phone will ring. If they use your email address, both the pad and the phone will ring. Ifnthey use the new e mail address, only the pad will ring.
Ok?