One could start with the Teletype manuals on Nick's navy-radio.com web site. Then the 26 was a mainstay of amateur radioteletype in the 1950s, so old issues of RTTY may have some helpful hints. --- "Ya can argue all ya wanna, but it's dif'rent than it was." "No it ain't! No it ain't! But ya gotta know the territory." Meredith Willson, The Music Man