Tait TB8100 User Manual page 124

114 Part F: Configuring Channels
In the Add or Edit Signalling Profile dialog box, Tx Timers tab, the Anti-
Kerchunking check box enables this feature. If a transmission is short, either
the transmitter is not keyed up or there will be no tail timers, depending on the
option selected.
The Transmissions less than box specifies which transmissions are short;
those with a duration less than the value in the box. Anti-kerchunking is only
applied to short transmissions.
If the Will not key transmitter option is selected, short transmissions do not
key up the transmitter at all. In effect, this option lengthens the key-up time for
all radio users.
If the Will not enable tail timers option is selected, short transmissions are
transmitted but not given a tail timer. The base station becomes available to
other users quickly. The radio user hears nothing on releasing PTT and
therefore does not know whether the base station has responded.
Hang time
The hang time is the length of time at the end of each transmission when the
base station continues to transmit subaudible signalling after Tx keying has
ceased.
In the Add or Edit Signalling Profile dialog box, Tx Timers tab, the Hang time
check box enables this timer and the Duration box specifies the length of the
hang time.
Reverse tone burst
The base station can send a
This applies only to transmissions with a CTCSS tone. The reverse tone burst
consists of the same tone, but is out of phase with it. In suitable radios, this
quickly mutes the receiver.
Transmissions with a DCS subtone have an equivalent: the
Note:
DCS end tone. This consists of a 134 Hz tone that lasts 180 ms and
is not configurable.
In the Add or Edit Signalling Profile dialog box, Tx Timers tab, the Reverse
tone burst check box enables reverse tone bursts.
The Duration box specifies the length of the tone burst. You can specify this
in milliseconds or in cycles. If the burst has too many cycles, it comes back into
phase with the original subtone and the radio may detect it again, re-opening
the receiver gate. Specifying the duration in cycles for different CTCSS
frequencies can help prevent this.
The Phase angle box specifies the amount that the burst is out of phase with
the original CTCSS subtone. If you select +120 or -120 instead of 180, more
cycles are required before the burst comes back in phase with the original
subtone.
reverse tone burst at the end of each transmission.
MB8100-00-00-806 © TEL 2003