A 3.5mm (1/8”) stereo plug is required. Do not use a mono plug. Connections are as follows:

• The tip is the speaker output. 
• The center conductor is the PA output. 
• The shaft is ground. 

Whether you use an external speaker or a PA speaker, you must use a stereo plug wired as above. If you have both an external speaker and a PA speaker, they can both be wired to the same plug.

When using an external speaker, you will get sound from both the external speaker and from the handset speaker.

To use the PA speaker, the radio must be switched to PA mode (in the user settings). Please note that you will hear radio traffic on the PA speaker while in PA mode, so that you can still receive incoming radio calls. If you do not want to hear radio traffic, simply turn the squelch all the way up. Use the volume control to adjust the PA volume.

NOTE: It is NOT possible to use the same speaker for both PA and as a regular extension speaker. Doing so will cause a squealing noise. However if you disconnect the speaker in the handset, then it is possible to use the same speaker for both PA and external speaker. The handset speaker will then no longer function and you must always use an external speaker.

To disconnect the speaker in the handset, open the handset and cut the green wire going to the speaker. This simple modification will not void the warranty.  A label should then be placed on the microphone describing the modification so that if the radio ever needs servicing, the repair technician will be aware of the modification.