Building your own DEC VAXstation 3100 serial cable

  1. Buy a 6-conductor phone cord.
  2. On ONE end of cord ONLY: Tear off clip from modular plug.
    Use fine saw to saw off remaining bump from clip.
    Use rough then fine sandpaper to smooth out plastic where clip was.
  3. Buy a wire-it-yourself FEMALE-DB9 -to- FEMALE-RJ45 adapter.
  4. Plug OTHER end of 6-conductor phone cord into RJ-45 jack in adapter.
  5. Wire up adapter as follows: 
     1 2 3  4 5 6
 | | |  | | |
|| | |  | | ||   Bare conductors facing you.
|| | |  | | ||
|            |
----\---/----|
    |   |
    |   |
MMJ                DB9
 1  brn    - dtr -  4
 2  yel    - tx+ -  3
 3  grn    - tx- -  5
 4  red    - rx- -  5
 5  blk    - rx+ -  2
 6  orange - dsr -  6

------------- --------------
\ 1 2 3 4 5 / \ 5 4 3 2 1 /
 \ 6 7 8 9 /   \ 9 8 7 6 /
   -------       -------
      Male       Female

Phone jack  DB-9 jack
----------  ---------
    1           5
    2           4
    3           2
    4           5
    5          snip
    6           6
           snip 7,8,9
  6. Plug sanded-down end of 6-conductor phone cord into PRINTER PORT on VAX.
  7. Set Dip switch 3 (the one between SERIAL PORT 2 and the LED lights) UP.

Now you will need a null modem adaptor to attach a VT100 terminal to the VAX using this cable and adapter.

Find an error or omission? Sorry about that! Please e-mail Eric at eric@ericshalov.com and let him know!

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©Copyright 2007 Eric Shalov. All Rights Reserved.