Paxar Monarch RF Link 7400 Operating Instructions Manual page 6

Printers
To install external RF link modules onto the printers:
1.
Insert a 9-volt (PP3) battery in the module. See "Inserting Batteries" for
more information.
2. Attach VELCRO
module. Place the VELCRO so the cable on the module can reach the
serial port.
3.
Using the VELCRO, attach the module to the printer. Note that on the
Renegade 4 printer, you must place the module so the cable faces
down. On the Rascal printer, place the module so the cable faces up.
9490 Printer
4. Insert the cable from the module into the printer's serial port.
6 RF link Operating Instructions
to the serial port sides of the printer and the external
9450 Printer