Cable, 1 m (3.281 feet), Compaq/HP iPAQ 310, 312, 314, 316 or 318 Travel Companion PNA (Personal Navigation Assistant) or Mio Moov M400 to Goddard PS-5a
miniUSB connector -> DB-9m connector, This cable provides complete communication between the units as well as passing +5 VDC power from the PS-5a to the PNA.  The cable includes an inline RS-232 voltage level converter which converts the RS-232 standard signal levels to 3.3 volts as required by the iPAQ 310.  

Note: Testing indicates that serial communication with the iPAQ 310 is possible only at 9600 baud or higher.  It does not work at 4800 baud.  Unfortunately, that means that it will not work with a Cambridge 302 because the 302 reverts to 4800 baud at power-up.  Likewise, the Garrecht Volkslogger and LX Colibri are stuck at 4800 baud, so they won't work with the iPAQ 310 either.  However, EW microRecorders and many LX Navigation products work fine at 9600 baud.

***Note: This photos is out of date, the circuit board is now mounted inside the DB-9 connector - eliminating the inline box.***