QST network fans Here is a link to a manuscript (in process) by Dave, G3NYH, that provides the most info I've ever seen in one place regarding matching networks & their associated math. http://www.g3ynh.info/zbook/index.html You'll have to register to view it but, it is worth the small effort. 73 & Good evening, Marv WC6W * ___________________________________________________________________ Try Juno Platinum for Free! Then, only $9.95/month! Unlimited Internet Access with 250MB of Email Storage. Visit http://www.juno.com/value to sign up today!