I have a couple or article in the older Radio electronics and Popular electronics magazines on the Distinctive ring. I assume ( but we know how that can be) that if it is in one of these mags, if must be pretty uniform. Looks like they count the rings during for sertain amount of time based on the start of the first ring. -- http://www.piclist.com hint: To leave the PICList mailto:piclist-unsubscribe-request@mitvma.mit.edu