Xref: utzoo comp.protocols.appletalk:5016 comp.sys.mac.comm:2118 Path: utzoo!utgpu!watserv1!watmath!att!linac!pacific.mps.ohio-state.edu!zaphod.mps.ohio-state.edu!julius.cs.uiuc.edu!apple!agate!darkstar!ucscb.UCSC.EDU!woody From: woody@ucscb.UCSC.EDU (Bill Woodcock) Newsgroups: comp.protocols.appletalk,comp.sys.mac.comm Subject: Re: do I need phone net connectors? Summary: Yes, you do. Message-ID: <10774@darkstar.ucsc.edu> Date: 9 Jan 91 01:20:56 GMT References: <1991Jan7.165900.1538@ccu.umanitoba.ca> <1991Jan8.090043.25113@sics.se> Sender: usenet@darkstar.ucsc.edu Followup-To: comp.protocols.appletalk Organization: University of California, Santa Cruz Lines: 40 > This is very strange in my opinion. An ImageWriter cable is > a standard serial cable for mac and is intended for > connection of two RS-422 ports. There should be no > difference electrically connecting a mac to mac, mac to > modem, mac to LaserWriter or mac to ImageWriter. > > AppleTalk is software and I don't think software could feel > the difference how you electrically connect the devices in > this case. > > The intention of the LocalTalk box is to let you mix output > signal from different ports and is needed if more than two > LocalTalk equipment are connected. There is no magic in > these boxes. Actually, the main reason for using a LocalTalk transciever box like a Farallon PhoneNet connector is to prevent your SCC chip and potentially your motherboard from being fried by static and higher- than-5v-charges coming in off the port. LocalTalk transcievers by and large do two things: they combine the T+ and T- and R+ and R- onto a single balanced pair, and they provide surge suppression and protection from voltage spikes. -Bill Woodcock BMUG NetAdmin _______________________________________________________________________________ 0000 : 0600 0800 7700 FE00 FF 0 FF8 7F 0 3 00 48 bill.woodcock.iv 0010 : CC00 7C00 0C00 1000 2800 440 8200 40 0020 : C000 4000 8000 C000 C 00 800 80 48 0 9 woody@ucscb.ucsc.edu 0030 : FF00 F000 7F80 CC00 CC 0 7 80 7 80 CC 6 0040 : CC00 7F80 9800 7800 CC00 CC0 CC 0 C 00 2355.virginia.st 0050 : CC00 CC00 FC00 CC00 CC 0 2000 10 0 7 00 C 0 0060 : CC00 CC00 CCC0 4800 2 00 1 00 2 00 48 0 9 berkeley.california 0070 : 4800 2400 1200 1000 2800 4 00 8 00 E0 0080 : 3000 6000 F000 6000 000 60 0 600 C0 0 01C 94709.1315 _______________________________________________________________________________