hp_38g_serial_cable_wiring

1   2   3   4   5
  6   7   8   9

DB-9 Male

1 - Red - Signal Ground - Pin 4 (Yellow)
2 - Yellow - DTE Ready - NC
3 - Blue - Transmitted Data -
4 - White - Received Data



Instructions reversed

HP-38G | DB-9
-------+-----
   1   |metal shell (optional)
   2 tx|pin 4
   3 rx|pin 3
   4   |pin 1
-------+-----


so...

shield --> white
white --> blue
blue --> red
red --> yellow