hovan@bgsuvax.UUCP (John Hovan) (01/12/88)
Does anyone know what makes appletalk connectors special? A few
readings with an ohmmeter showed that the connectors are not merely a straight
though cable. One possible explanation is that the box supplied with
appletalk has an optically isolated circuit inside its 2" x 1" mysterious
box. Has anyuone been brave enough to open one of these boxes and solve the
mystery??? If you have, please let me know! They cannot be complex since
the appletalk hardware only uses 3 wires from the computers subminature
din-8 jack.
John Hovan
Bowling Green State University
Hardware Support
hovan@bgsuvax.uucp
N8JAAmatt@shorty.CS.WISC.EDU (Matt Schaefer) (01/18/88)
In article <1498@bgsuvax.UUCP> hovan@bgsuvax.UUCP (John Hovan) writes: > Does anyone know what makes appletalk connectors special? A few >readings with an ohmmeter showed that the connectors are not merely a straight >though cable. I remember seeing schematics in a very recent issue of Computer Shopper of the innards of Appletalk cables. It was definitely not a straight-through cable. There was also a schematic of how to make a "cheater" cord if you only wanted to connect two devices together. I'll have to wait until I get home to check which issue. Matt Schaefer ...!{harvard,ihnp4,rutgers,ucbvax}!uwvax!matt UW-Madison Computer Sciences Laboratory matt@cs.wisc.edu
ephraim@think.COM (ephraim vishniac) (01/21/88)
In article <1498@bgsuvax.UUCP> hovan@bgsuvax.UUCP (John Hovan) writes: > Does anyone know what makes appletalk connectors special? A few >readings with an ohmmeter showed that the connectors are not merely a straight >though cable. One possible explanation is that the box supplied with >appletalk has an optically isolated circuit inside its 2" x 1" mysterious >box. Has anyuone been brave enough to open one of these boxes and solve the >mystery??? If you have, please let me know! They cannot be complex since >the appletalk hardware only uses 3 wires from the computers subminature >din-8 jack. I opened up an AppleTalk connector last year, and found an isolation transformer and a trivial amount of wiring. The connector box is glued shut, but it's possible to open it without damaging the contents by prying carefully all the way around the seam. You'll undoubtedly inflict some cosmetic damage, but not very much if you're careful. BTW, bgsuvax complains that "hovan" is an unknown user! Ephraim Vishniac ephraim@think.com Thinking Machines Corporation / 245 First Street / Cambridge, MA 02142-1214