Open Voice Channel Mode
Open Voice Channel Mode (OVCM) is a standard feature in the majority of MOTOTRBO radios that become available in software release R2.10.0[1]. When setup to use OVCM, a radio can participate in a talkgroup call it would normally not be able to transmit or receive on.
OVCM also supports broadcast calls as well as individual calls.
The Network Application Interface (NAI) for third party voice applications supports OVCM calls, except for phone calls.
OVCM calls are supported on Direct Mode (Simplex); Dual Capacity Direct Mode (Simplex with inter-radio synchronization); Single Site Repeater; Extended Range Direct Mode (Single-Frequency repeater) and IP Site Connect systems.
If OVCM is set to interruptible, the call can be interrupted to support Voice Interrupt; Emergency Voice Interrupt; Data Over Voice Interrupt and Remote De-Key.
Contact Type (OVCM TX) supports initiating OVCM calls, while Channel Configuration OVCM (OVCM RX) supports participating in an OVCM call. All group and individual contacts can be configured with OVCM TX and OVCM RX enabled or disabled, with disabled being the default option. When OVCM TX is enabled for a group or an individual contact, the Subscriber Unit (SU) indicates the call is in OVCM.
The radios can be configured to allow OVCM RX. In this case, the radio can participate in calls which would otherwise require special configuration. OVCM RX is configurable at the personality level.[2]
Operation
| TX | RX | Expected Behavior |
|---|---|---|
| OVCM TX Enabled | OVCM RX Enabled | The radio can initiate an OVCM call.
The radio receives any OVCM call. The user can reply to an OVCM call. |
| OVCM TX Enabled | OVCM RX Disabled | The radio can initiate an OVCM call.
The radio cannot receive any OVCM call. if it not the target or not in a targeted talkgroup. Receives an OVCM call if target or member of a targeted talkgroup. The user can reply to an OVCM call. |
| OVCM TX Disabled | OVCM RX Enabled | The radio cannot initiate an OVCM call.
The radio receives any OVCM call. Talks back to an OVCM call indicating OVCM. |
| OVCM TX Disabled | OVCM RX Disabled | Does not initiate an OVCM call.
Does not receive an OVCM call if not a target or member of a targeted talkgroup. Receives an OVCM call if in a targeted talkgroup or called itself. Talks back to an OVCM call indicating OVCM. |
Notes
Radio firmware R02.10.00.0001 (or later) and repeater firmware R02.10.00.05 (or later) are needed to support OVCM. CPS2 version 2.18.95.0 (or later) is also needed. All of these releases date from around 2019.
See also
References
- ↑ MOTOTRBO® System Release Notes. Professional Commercial Radios (PCR) & Accessories. Version: R2.10 Date: May 13, 2019. Retrieved 27.07.2021
- ↑ New: Unaddressed; Broadcast and Open Voice Channel Mode Calls Retrieved 27.07.2021