AJK's ReSisterNet
Note: an "O" means a connection.
Note: an ">" is a connector plug pin.
Note: an "#" is there only to seperate sections. See below for
a schematic without them if this confuses you.
Note: keep wire from computer to dongle as short as possible.
Note: keep wire from dongle to terminator under 2 meters. (about 6ft)
Section A is the dongle.
Section B is the terminator.
Section C is the main junction box.
Section D is simply the colors of the wires.
###############################################################
section A # B # C # D
###############################################################
# # #
# # #
+tx >-----------------. # # #
| # # #
R1 100K | # # #
-rx >----/\/\/\/\-----O-------------->>-O-->>-O-->>- CAT3 blue-white
# | # | #
# / # / #
# \ # \ #
R3 1M / # / **R5 1M
# \ # \ #
# / # / #
# \ # \ #
R2 100K # | # | #
-rx >----/\/\/\/\-----O-------------->>-O-->>-O-->>- CAT3 blue
| # # | #
| # # / #
-tx >-----------------' # # \ #
# # / #
**R4 1M \ #
# # / #
# # \ #
# # | #
gnd >-------------------------------->>---->>-O-->>- *CAT3 all unused wires
# # #
# # #
# # #
Same schematic without the sections marked, incase the above is unclear to you:
+tx >-----------------.
|
R1 100K |
+rx >----/\/\/\/\-----O-------------->>-O-->>-O-->>- CAT3 blue-white
| |
/ /
\ \
R3 1M / / **R5 1M
\ \
/ /
\ \
R2 100K | |
-rx >----/\/\/\/\-----O-------------->>-O-->>-O-->>- CAT3 blue
| |
| /
-tx >-----------------' \
/
**R4 1M \
/
\
|
gnd >-------------------------------->>---->>-O-->>- *CAT3 all unused wires
* Ground is optional, but makes the system faster as a whole. If in doubt,
include it. I highly reccomend it's use!
** Static drain resistors also optional. Only one required in the entire
system. Place at a main junction box, where any connection will pass through.
Physical star topology reccomended if used. Otherwise, you will need to
work out something else that will do this for you if you daisychain.
This circuit was designed because "CapNet" did not perform well enough on
long cable runs and I lacked apple's dongle. Not tested as compatable with
any other system (including "Capnet"). Please let me now if it is.
R3 is a terminator, and should ALWAYS be in-place. It can either be wired
behind an outlet, or into a plug with another outlet.
R3 is NOT part of the dongle.
PARTS LIST FOR ONE NODE IN STAR TOPOLOGY:
DIN/DB9 for connection to serial port.
R1,R2 100K ohms (brown black yellow)
R3 1M ohms (brown black green)
Optional: wall jack
FOR A BUSS TOPOLOGY, ONLY TERMINATE THE FAR ENDS OF THE CABLE.
MIXED TOPOLOGY WORKS TOO.
PARTS LIST FOR MAIN JUNCTION:
Junction box or wiring block, telephone wire blocks are OK.
Optional: R4,R5 1M ohms (brown black green)
OTHER PARTS:
Enough CAT3 to reach each computer.
Bare price per node is under 25 cents, V.S. $1 for capnet, depending on how
you build it. It should not cost over 75 cents per node.
I found all needed parts in my junk box, so it was a free project for me.
*** WARNING! *** WARNING! *** WARNING! *** WARNING! *** WARNING! ***
NOT RECCOMENDED FOR USE BETWEEN BUILDINGS!
If you need to connect between buildings use proper 1:1 isolation
transformer and DO NOT connect grounds between buildings!
*** WARNING! *** WARNING! *** WARNING! *** WARNING! *** WARNING! ***
Pinouts of ports:
DB-9 (female, looking at the rear of the Mac)
.---------------------.
\ 5 4 3 2 1 /
\ 9 8 7 6 /
`---------------'
+tx 4
+rx 8
-tx 5
-rx 9
gnd 3
MINI DIN - 8 (female looking at the rear of the Mac)
____ ___
/ \/ \
/ \
/ 8 7 6 \
| |
| 5 4 3 |
\__ __/
/ 2 1 \
`---------'
+tx 6
+rx 8
-tx 3
-rx 5
gnd 4
