Midian TRA, Instruction Manual

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N-Click Timeout: This sets the maximum time
allowed between clicks before the click decoder is
reset.
Typically, N-Click Decode is programmed for 5 to 7
clicks. Fewer clicks can result in falsing on noise. N-
Click Timeout is typically set to 0.1 to 0.2 seconds.
Programming too long a time here may also result in
falsing. The TRA automatically rings when decoding N-
clicks.
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Hot Dialing Time: This programs the Hot Dialing
time from 0.0 to 9.9 seconds. This is how long the
PTT will remain up between keypad entries.
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VOX Hold Timer : This timer prevents the PTT
from dropping out between words, and can be set
between .0 and .9 seconds. This timer is normally
programmed from .5 to .8 seconds.
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Scan Step : This permits selecting either three line
binary scan (for a maximum of 8 channels) or step
scanning for radios employing push button channel
steppers.
3.10. System Parameters
Miscellaneous system parameters are programmed here.
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Queuing Signal Delay: This sets the transmit
Queuing Signal Delay time. When making a call in
an RTX system, the scanner looks for a non-busy
channel after the user comes off hook. (A channel
is considered idle if no carrier is sensed.) If the TRA
fails to find an empty channel when the user comes
off hook, the TRA generates a busy tone. After the
user hangs up, the TRA enters a
Queuing mode,
while it looks for an available channel. After a
channel has been clear for the time programmed
here, the TRA will ring the telephone for
approximately 160 msec to inform the user that a
channel has become available.
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COR Active Input Level: This determines
whether a ground or V+ indicates a busy channel.
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Squelch Active Input Level: This determines
whether a ground or V+ is used to squelch the
radio audio output amplifiers. The polarity of diode
D3 may also need to be reversed using JU7. In
normal operation, it is not necessary to use the
Squelch Output wire, because the earpiece audio
in the telephone handset is muted by the TRA and
the radio speaker serves no purpose.
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Busy Lockout, # Channels to Scan: Entering 00
disables both busy lockout and radio channel
scanning. Entering 01-16 determines the number
of channels to be scanned. When using binary a
maximum of eight channels can be scanned (three
lines). When step scanning, a maximum of sixteen
channels is available. During step scan the radio is
scanned in a circle. The TRA needs to know when
it has gone through the circle so that it can
determine whether all channels are busy and
should give a busy indication and start the queuing
timer.
The channel scanner controls an open-collector output
that is used to step the radio to the next channel or the
Least Significant Bit (LSB) of a binary address. (See
installation section for the Violet Wire.) This can be wired
to the channel-advance button on many synthesized
radios or to the LSB of radios with binary channel
advance.
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Scan Pulse Time/Synthesizer Lock Time: This
sets length of time that the scan output is active. In
step radios this time should be set for a period that
guarantees that the output is recognized by the
radio's step channel advance input circuit. In
binary radios this time would represent how long
the synthesizer takes to lock.
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Scan COR Detect Time: This sets the minimum
length of time that the radio takes to advance and
lock on to and provide a Carrier Present indication
to the COR Input lead.
During decode in RTX-compatible systems, the channels
are scanned for a DTMF
D collect tone. Once a DTMF D
tone is found, the scanner remains locked on the channel
until the number has been decoded. If it matches one of
the Decode Numbers (1, 2 or 3), scanning is disabled
while ringing occurs. Answering the call during ringing will
lock the scanner on the current channel.
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Dial Tone and Talk Beep: This Dial Tone function
determines whether or not the TRA internally
generates its own Pulsating Dial Tone while waiting
for a number to be dialed. This feature is generally
used for In-Plant Paging systems. The Talk Beep
feature enables an audible tone after paging tones
have finished. Entering a 0 disables both the dial
tone and talk beep. A
1 enables the dial tone and
disables the talk beep. A 2 enables the Talk Beep
but disables the dial tone. Entering 3 enables both
the dial tone and talk beep. See Table 12.
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System Type: This indicates to the TRA the type
of system in which it is being used. Enter a 1 if the
unit will operate in half duplex; enter a 2 if the unit
will operate in simplex; and enter a 0 if the unit will
operate in full duplex.
3.11. System Timers
The settings in this location control various timers. After
an ANI is sent, the call length timer is started.
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Call Limit Time : This sets the maximum length of
time a call may last before forcing a disconnect.
Programming this to 000 will disable the timer.
Setting this to 001 to 999 will set the timer to run for
that many seconds. A warning beep in the
earpiece is generated one minute before auto
disconnect.
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VOX Keyup Limit: This is the maximum length of
time that the TRA will generate PTT with a
continuous voice input, before timing out. This
prevents background noise from keeping the TRA
keyed continuously if the telephone was
accidentally not placed back on the hook. Setting
this to 00 will disable timeout; setting it to 01-99
allows the unit to operate for that many seconds.
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No VOX Activity Disconnect Time: If the TRA's
VOX has not detected any voice activity within the