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Serial DB9 9 Pin Male  connector Pin out
fig 2
Information on connecting a serial DB9 9 pin female connector to a Inspeed vortex anemometer
Additional parts:

You will need to order a DB9 connector from ebay thay are about 1.95

USB 2.0 to RS232 Serial Port DB9 9 Pin Male Converter Adapter Cable

If you have no serial port/or would prefer to use a USB slot
use a USB to DB9 / serial connector
Solder the connections to the DB9 female connector , please see diagram fig 2 , there are only two wires to solder pin {4} and pin {6} reassemble the connector housing

You're going to need a soldering iron,and solder, this is for soldering the two connections on the DB9 connector, a couple of screwdrivers.

DB9 Female connector
Serial DB9 9 Pin Female connector