Tait TB8100, User Manual

Page: 140 / 254

130 Part F: Configuring Channels
© Tait Electronics Limited December 2007
Subaudible filter
Select the Subaudible filter check box to filter subaudible signalling out of the
audio sent to line. This enables
an additional high pass filter, which achieves
an audio level at 250 Hz that is 35 dB lower than the level at 1 kHz.
(Selecting this check box has no effect if the subtone table specifies a subaudible
tone or code with the action ‘Gate Receiver.’ Selecting a tone or code with this
action automatically enables the additional high pass filter.) This additional filter
only has an effect if the signal path in the current channel profile selects one of
the speech filters.)
Subtone table
In the Add or Edit Signalling Profile dialog box, a table defines up to 16
subtones that the receiver will accept and specifies the base station’s response.
The left-hand side specifies the receive response and the right-hand side the
transmit response.
The table lets you configure the base station as a community repeater, with each
subtone having its own group of users. It also lets you set up the means of
remotely initiating
Task Manager actions . A radio can send carrier with a
particular subtone and the decoding of this subtone initiates a Task Manager
action. The left side specifies a subtone. The base station will recognize
transmissions containing that subtone. The row defines the base station’s
response.
Decode Signal Specifies a subtone and instructs the base station to decode it. To begin adding
a subtone to the list that the base station will recognize, click in the cell. A
pop-up menu appears. Click an option.
Note: When specifying CTCSS tones, select frequencies that are
spread out across the available range. Do not select tones that are
close to one another in frequency, as the tone reject bandwidth may
not permit separating them. For example, if 67 Hz is received, both the 67 Hz
and the 69.4 Hz decoders may operate. The exact select and reject bandwidths
vary, see
“CTCSS characteristics” on page 93 . When you select a subtone, it
becomes unavailable. This is to prevent you selecting the same subtone twice.
Note:
When specifying DCS codes, you need to be aware that there
is an inverse code that is exactly the same. For example, if you
specify 047, the receiver will unmute to 047 and to 023i. Both these
codes then become unavailable, to prevent you selecting the same code or its
equivalent inverse again.