Tait TM8000 Service Manual page 43

When this check box is selected, the
TX Tail
Enable
Also known as transmitter hang time. After a valid TX key signal has been removed
TX Tail Timer
from the TA2922 board input, the radio transmitter continue to be keyed for the
period of this timer. Note that line input audio is not muted during the TX tail
and any line audio present during the TX tail is passed to the radio transmitter.
Adjustable between 0.1 and 25.5 seconds
After the TX key signal is removed and the radio stops transmitting, if the radio
Anti-
Kerchunker
begins receiving immediately afterwards, the TA2922 board delays the activation
of the RX gate signal according to the Anti-Kerchunker timer. This is used when
linking to repeaters that have a transmitter tail or hang time.
When the Anti-Kerchunker timer is set to the same duration as the repeater tail,
this prevents the repeater tail from affecting link radio operation.
Adjustable between 0.1 and 25.5 seconds
When this check box is cleared, the RX line audio source is the radio's
RX Line Out
uses RX_AUD
programmable AUD_TAP_OUT audio source, resulting in a fixed line level with
the flat/de-emphasised response set according to the tap point location
programmed in the radio software.
When this check box is selected, the RX line out audio source is after the radio
volume control. This results in de-emphasised variable level line audio output level.
Note that in some TM8000/TM9000 configurations, the RX_AUD line becomes
fixed in value, such as when multi-head configurations are used, or with some
remote head options. Consult your Tait dealer for more information.
If the radio IOP_GPIO5 line becomes active (low), the TA2922 board outputs a
MIC PTT on
IOP_GPIO5
valid RX gate signal. This is for applications where receiver line audio out must
carry audio from the radio's receiver as well as audio from the control head fist
microphone. The is possible when the radio is programmed so that a microphone
PTT press is mirrored on IOP_GPIO5, and the programmable audio from Mic
PTT is configured to split the audio to a Tap Out location.
When this check box is selected, the Powerup Serial Timer is enabled (see below)
Powerup
Serial Timer
to enable serial data to be passed transparently from the radio's internal option
Enable
connector to the RS-232 lines on the option TA2922 board I/O
When the Powerup Serial Timer expires after power on, all serial data to/from the
Powerup
Serial Timer
radio internal options port is transparently routed to the option TA2922 board RS-
232 I/O lines for communication with external data equipment, e.g. GPS or a
CCDI interface.
The purpose of the Powerup Serial Timer is to provide a short period of time
where the TA2922 board can be read or programmed by the programming
application. After the Powerup Serial Timer expires, the TA2922 board is only
TA2922 Universal Line Interface Service Manual
© Tait Electronics Limited March 2010
TX Tail Timer is enabled.
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