Instruction manual

ACU-1000 Operations Manual
Interoperability Now 2-107
interpreted as control characters intended for other equipment and all DTMF (other than the
DTMF sequence that signals the module to return to the command mode) is not interpreted as
control commands. See Section 3.5.1.9 for more information about the Command and Data
Modes.
While in the Data Mode, the DTMF from the local phone is detected by the LP module and
relayed via the CPM-4 module to the cross-connected PSTN-2 module as parallel data. The
PSTN-2 regenerates and transmits the DTMF characters into the phone line.
When the system is used in this way, the DSP-2 module should have its DTMF Mute Timer
turned on, so that only the regenerated DTMF will be sent via the phone line.
2.17.4.1.2 Transmitting DTMF via a Module other than the PSTN-2
If it is desired that DTMF characters be passed through the system, being sent out by a module
other than a PSTN module, the DTMF mute timer must be turned off. This is required because
only the PSTN regenerates DTMF; the others will just pass it through like any other program
audio. The DTMF mute timer must be set to off on the module that receives the DTMF or it
cannot be passed on to the cross-connected module or modules.
2.17.4.2 RX Audio Delay
An adjustable delay can be added to the LP-2’s input audio. When speech first appears in the
input audio, some time passes before the VOX algorithm can detect it. The adjustable audio
delay prevents the loss of the audio that is received before the detection takes place and audio
gates can be opened to send this audio on to other modules.
2.17.4.3 VOX Threshold
This command setting determines the sensitivity of the LP-2 VOX. There are three levels
(Low, Med. High) and Off.
2.17.4.4 VOX Hang Time
VOX hang time determines how long the VOX stays active after speech disappears. This keeps
radios that are communicating with the LP module from unkeying between words spoken by
the LP user. If too short a hangtime is set, the radios will unkey frequently and syllables may
be missed during the time it takes the transmitter to key. Too long a hangtime causes the party
at the other end to wait unnecessarily long for the VOX to unkey before beginning their
response during the conversation.
2.17.4.5 Module Security Level Selection
This command sets a module’s security level number. 0 = not secure (no PIN required), 1 =
least secure, up to 9 = most secure.
2.17.4.6 Dial & Busy Tone Style
The Local Phone Module generates the dial tone and busy tone sent to the phone that is
plugged into it. When the handset of the local phone is picked up, this dial tone is heard in the
earpiece. After a request to make a connection is made, the user will hear the ring cadence as