Microphone
The microphone of a 10-4 cell phone is in the lower part of the phone and it is very sensitive. The microphone should be kept approximately 30 cm from your lips. If you talk too close to the microphone, the other party will only hear garbled sounds.
Loudspeaker
The 10-4 Service includes an adjustable speaker. The speaker in "On" by default and set to signal incoming 10-4 calls.
If the cell phone is set to vibration mode or the ring tone is turned off, you will not hear the tone signal for incoming calls, and voice communication will be transmitted through the earpiece. To access the same feature, you can press the SPEAKER button when you are receiving a 10-4 call.
To silence the speaker of your 10-4 cell phone:
- From the 10-4 menu, select Options (right select key).
- Scroll down to Settings, then select Loudspeaker.
- Scroll down to Off, then press Menu/OK.