Re: Localtalk card questions.

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Jon Bettencourt wrote in message ...

>I would be interested in building a cheap localtalk hub! Or at least with
>more specific instructions on how to use the three PhoneNet connectors I
>have (does it require an actual phone line or do I just connect them using
>phone cables? do I need all 4 wires in the cable or does it use 2 like a
>standard telephone? can they be connected in parallel like telephones? can
>I just use two unused phone line wires in the house?).


Jon,
    Phone cable is enough, doesnt need a phone jack, as such. (Though if you
have one to spare, it means not having cables snake all over the house.) If
i remember correctly, only uses 1 pair, the outer. You can connect phone
over the same wire, as it uses the opposite pair, but not 2 localtalk
segments over the same cable (too much crosstalk, would ruin the data rate).
Using your 3 phonenets goes like this...

Phonet             A)                B)                 c)
Jacks             1   2<ph cabl>3  4<ph cabl>5  6

At this point, jacks 1 and 6 are unused, and I have heard some say they can
be left like that. However, the proper way is to terminate the bus (just
like with scsi or 10base2). You do that by plugging localtalk terminators
into those jacks, or making your own, if you don't have any. You'll need
rj11 crimpers, a tool that can be bought at walmart for $5. You'll need rj11
plugs, which can be bought, likely on the same shelf even. You'll need 2
resistors, which can be bought at Radio Shack. 120ohm 1/4 watt resistors
will be fine, and i believe the color code for them is brown/red/brown/gold.
It's obvious how the crimpers work, once you have them, you insert a rj11
plug, and in this case, instead of putting phone cable in the plug, you'll
put the resistor. The resistor has 2 wire leads, and these leads should be
in pins 1 and 4 of the plug (the outer pair). Bend the wire leads of the
resistor so that they look like this...

,-{resistor}-,
|___    ___|
      |   |
      |   |

Bend gently, while resistors are cheap, you don't want to break them and
have to give your biography to the Radio Shack bureacrats again.

John