You will also need the ADB cable, (part number WI300), that came with your HeadMaster Plus. This is pictured below on the right side.
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You will need a USB adapter in order to connect your HeadMaster Plus to the USB port on an IBM compatible or a Macintosh computer. We currently recommend the Imate Universal ADB to USB adapter from Griffen Technology.
You will also need the ADB cable, (part number WI300), that came with your HeadMaster Plus. This is pictured below on the right side.
1. Turn your computer OFF and disconnect the HeadMaster Plus charger (BCPS-1) if it is plugged in.
Configure the 3 buttons on the side of the HeadMaster's main control unit to reflect the Macintosh setting, even if you are connecting to an IBM compatible.
2. The first two buttons should be in the OUT position and the last one pushed IN (pictured below from front to rear).
3. Next, connect one end of your ADB cable (WI300) to the ADB connector on the back of the HeadMaster, pictured below.
4. Connect the other end of your ADB cable to the female ADB end of the Imate adapter.
5. Connect the USB end of the Imate adapter to the USB port on your computer (this may be on the front of your computer, the back, or both).
6. Plug one end of the BCPS-1 battery charger that came with your HeadMaster into the HeadMaster's charging jack. Plug the other end into a working wall outlet. The power LED on the HeadMaster will light up.
7. The basic connections from the HeadMaster to the USB port on the computer should look similar to the picture below. 
8. With all the proper connections made, and your headset connected to the main unit, you can now turn on your computer. The HeadMaster Plus should work properly.
9. If you would like the HeadMaster Plus operator's manual you can download it in PFD format at http://www.prentrom.com/downloads/computer-access-manuals?id=122