Relay-Version: version B 2.10 5/3/83; site utzoo.UUCP Path: utzoo!mnetor!seismo!lll-lcc!ptsfa!well!rab From: rab@well.UUCP (Bob Bickford) Newsgroups: comp.periphs,comp.terminals,comp.dcom.lans Subject: Re: Telco-style push down blocks and stranded cable Message-ID: <2316@well.UUCP> Date: Wed, 7-Jan-87 08:15:54 EST Article-I.D.: well.2316 Posted: Wed Jan 7 08:15:54 1987 Date-Received: Wed, 7-Jan-87 21:49:36 EST References: <2551@phri.UUCP> Distribution: world Organization: Whole Earth Lectronic Link, Sausalito, CA Lines: 36 Summary: no stranded wire in telco blocks Xref: mnetor comp.periphs:108 comp.terminals:116 comp.dcom.lans:118 In a previous article Roy Smith asks: > > What I want to do is set up a panel with a termination for each > port on one side and a termination for each external line on the other and > patch between them as necessary. Since patching won't be frequent, I don't > need anything as fancy as plug-in patch panels; re-doing a punchdown jumper > will be easy enough. The problem is that we've got miles of Belden 8723 > (stranded shielded twisted pair) all through the building and I understand > that punchdown blocks are made to only work with solid wire. Has anybody > tried using stranded wire in punch-down blocks? Will it work? The last > thing I want is to have hundreds of connections start to work themselves > loose in a year or two. > Nope, it won't work. I've done this; it will come back and haunt you (or your successor) if you try it. The whole mechanical design of the silly things (telco punch-down blocks) is centered around a single solid strand of the right size. If you stick to that, they're wonderful, though. On your wiring, the way you've set that up should give you wonderful performance. I was running between two and three hundred feet at 9600 baud on just plain old telco wire (doubled the signal ground) and it worked fine.... In fact, I believe the entire building was wired that way. Using the shield is both good and bad..... good if you have or suspect EMI problems, bad on long runs because of the extra capacitance. Don't have my Belden catalog handy, but I seem to recall that the stuff you mention is low-cap, so you should be ok. -- Robert Bickford {hplabs, ucbvax, lll-lcc, ptsfa, msudoc}!well!rab terrorist cryptography DES drugs cipher secret decode NSA CIA NRO IRS coke crack pot LSD russian missile atom nuclear assassinate libyan RSA The above is food for the NSA line eater. Add it to your .signature and you too can help overflow the NSA's ability to scan all traffic going in or out of the USA looking for "significant" words. (This is not a joke, sadly.)