User guide

6
Twintalker RC-6405
13 Using the Twintalker RC-6405
The display illustrations in next pages only show the icons or display
informations of the functions that are explained in the text.
13.1 Switching On/Off the PMR radio
• Turn the “On-Off/Volume Knob”
1
clockwise. A clicking
sound will indicate that the PMR radio is switched on.
• Turn the “On-Off/Volume Knob”
1
fully counter clockwise.
The clicking sound will indicate that the PMR radio is
switched off.
13.2 Battery Charge Level/Low Battery Indication
The battery charge level is indicated by the number of squares present inside the battery icon on
the LCD Screen.
Battery Full
Battery 2/3 charged
Battery 1/3 charged
Battery empty
When the battery charge level is low, the battery icon
will flash and a beep will be heard to
indicate that the batteries need to be replaced or recharged.
13.3 Adjusting Speaker Volume
• Turn the “On-Off/Volume Knob”
1
clockwise to increase
the speaker volume.
• Turn counter-clockwise to lower the volume.
13.4 Receiving a Signal
The unit is continuously in the receive mode when the unit is switched ON and not transmitting.
In order for other people to receive your transmission, they must also be
on the same channel and have set the same CTCSS code or DCS code.
( See chapter “13.6 Changing Channels” and “13.7 CTCSS (Continious
Tone Coded Squelch System) / DCS (Digital Coded Squelch)”.
Either CTCSS or DCS can be used but never both at the same time.
13.5 Transmitting a Signal
• Press and hold the
PTT
- button
12
to transmit. The TX
symbol is displayed.
• Hold the unit in a vertical position
with the microphone 10cm
from the mouth and speak into the microphone.
• Release the
PTT
- button
12
when you want to stop
transmitting.
To check the channel activity use the monitor function
( See chapter “13.8 Monitor” ).
13.6 Changing Channels
• Press the -button
7
once, the current channel number
flashes on the display.
• Press the
- button
11
or the - button
10
to change
the channel.
• Press the
PTT
- button
12
to confirm and return to stand-by
mode.
If no button is pressed within 5 seconds during setting, the unit will return
to standby.
13.7 CTCSS (Continious Tone Coded Squelch System) / 
DCS (Digital Coded Squelch)
License free PMR radio's operating on the 446 MHz frequency band, like the Twintalker RC-6405
PMR, have 8 available radio channels. If there are many PMR users in your neighborhood, there
is a chance that some of these users are operating on the same radio channel.
To prevent that you receive signals from other users,
sub-channels have been integrated.
Two PMR radio's will only be able to communicate with each other when they are operating on
the same radio channel and when they have selected exactly the same sub-channel.
There are two kind of sub-channels :
• Continuous Tone Coded Squelch System (CTCSS)
• Digital Coded Squelch (DCS)
When using CTCSS, a low frequency tone (between 67 and 250 Hz) will be transmitted along
with the voice sig
nal. There are 38 available tones to choose from. You are free to choose one
of these 38 available tones. Due to filtering, these tones will generally not be audible so they will
not disturb the communication.
DCS is similar to CTCSS, but instead of sending a continu
ous tone of a selected frequency, a
digital data transmission is added to the radio signal. This Digital Code is transmitted at a really
low rate, around 134 bits per second (the code is 23 bits long). Only the PMR's of the latest
generation will support DCS. There are 83 available DCS codes that can be used. Since earlier
models will only support CTCSS it will be better to use DCS to prevent that other users will be
audible during your PMR conversations.