Parts:

For a Vectrex cable:

https://www.aliexpress.us/item/3256806071594253.html   Sega extension cable ($4?)

For a USB cable:

https://www.amazon.com/NOYITO-PL2303TA-Converters-Raspberry-Programming/dp/B07CLDQ35P/  USB to TTL ($8 for 2)


For both:

https://www.amazon.com/dp/B08154MRHC                   DB9 Screw Terminal Block ($9 for 2)

https://store.atariage.com/products/atarivox-speech-synthesizer  AtariVox+ ($50)



looking into cable female plug):


    5   4   3   2   1 (TX)
  _____________________
  \ o   o   o   o   * /
   \                 /
    \ o   *   *   o /
     \_____________/
      9   8   7   6
         0V  +5V

       ______ 5
      / _____ 4
     / / ____ 3
    / / / ___ 2
   / / / / __ 1  TX  red
  / / / / /
  o o o o o
   o o o o
    \ \ \ \___ 6
     \ \ \____ 7  +5V   white
      \ \_____ 8  .GND  blue
       \______ 9

with my current cable, this is the colour scheme:
  1. red
  2. black
  3. almost orange, maybe a touch of pink
  4. orange, marginally more yellowish than (3)
  5. purple
  6. green
  7. white (+5v)
  8. blue (gnd)
  9. pale blue or pale cyan, might be mistaken for grey


These are the colour schemes I've determined from previous cables:

  1. red
  2. black
  3. light orange or dark yellow?   \____ careful! almost the same colour
  4. slightly darker orange         /
  5. reddish-brown? maroon?
  6. green
  7. pale yellow, but almost white
  8. cyan or pale blue
  9. grey? dirty white?


  1. green
  2. yellow
  3. orange
  4. red
  5. brown
  6. white
  7. gray
  8. black
  9. blue

  1. red
  2. black
  3. grey
  4. orange
  5. brown
  6. green
  7. white
  8. blue
  9. yellow 


  1. Red
  2. Black
  3. Gray
  4. Orange
  5. Brown-ish
  6. Green
  7. White
  8. Blue
  9. Yellow