no AN/APN-1 manuals here, but i did just pick up Radio Altimeter Gauge ID-14/APN-1, which i suppose goes to this setup? item is for sale. tnx, barry carson city, nv -- Barry Tuttleman Carson City, Nevada industrial-related website: http://home.att.net/~btuttleman/barrysite.html electronics-related website: http://home.att.net/~btuttleman2/electron.html