Grandstream Networks GXV300X - Manual (Page 51)

Grandstream Networks, Inc. GXV300x User Manual Page 49 of 54
Firmware 1.2.3.7 Updated: 12/2010
Headset Jack
F IGURE 10: H EADSET J ACK D IAGRAM
The left side of the diagram illustrates the RJ22 (handset plug) pin assignment; the right side illustrates
the 2.5mm headset plug. Additional adaptors are necessary to connect the phone to an external speaker
or intercom/paging system. (Adaptors can be purchased from an local electronics store).
Cross Over Cable For Some Model of Headset
If you want to use headset products with an RJ22 plug, a special cable (known as cross-over cable) or a
cable adapter box is required. The standard handset cable (supplied with the headset) is a roll-over ca-
ble standard for ALL handsets using RJ22 plug.
The default handset plug PIN lay out is China standard (Made in China). US and European customers
cannot use local popular RJ22 headsets without adjusting the connection wiring as follows:
EXAMPLE: C
ONNECTING A P LANTRONICS M12 H EADSET USING CLAMPING TOOLS AND RJ22 PLUG
Here are the schemas of the two cables; the plug viewed with Pin side facing user, and PINs layout as
specified above in the diagram:
d: SP +
c: Mic +
a: SP - b: Mic -