
The RT1121 Radio-to-Intercom Bridge Receiver integrates with existing wired Public Address (PA) intercom systems, allowing announcements via DMR digital two-way radios. Ideal for facilities requiring wireless access to their PA systems, the RT1121 enhances communication by enabling personnel to broadcast messages from their radios without being tied to a fixed intercom station.
Key Features:
- VHF & UHF Compatibility: Operates on either VHF (150-170 MHz) or UHF (450-470 MHz) business band frequencies, including Canadian business bands.
- Works with Repeaters: Supports communication through radio repeaters for extended range.
- Digital DMR Operation: Fully compatible with business band DMR two-way radios.
- Pre-Recorded Message Playback: Stores and plays up to four different messages, triggered by specific inputs or radio codes.
- Switch Input Activation: Automatically plays a pre-recorded message when a connected switch (e.g., door sensor) is activated.
- Relay Output for Strobe Light: Can trigger an optional strobe light for visual alerts.
- Message Playback Features: Includes delay and repeat playback options for enhanced message control.
- Advanced Audio Management: "Record and Play" buffers messages up to 70 seconds to prevent feedback when using radios near PA speakers.
- Pre-Announce Tone: Optional attention tone before announcements, with adjustable volume settings.
- Flexible Audio Outputs: Connects to a PA amplifier via a high-impedance, unbalanced AUX input or a 600-ohm balanced MIC input.
- Programmable Audio Levels: Adjustable output levels to match system requirements.
- PC & Field Programmable: Easily set frequencies and configurations within the supported VHF/UHF bands.
- Easy Installation: Plug-and-play design with included mounting brackets.
How It Works:
The RT1121 does not have a built-in PA amplifier and must be connected to an existing PA/intercom system with its own amplifier and speakers. When a valid DMR signal is received, the unit transmits the message to the PA system, allowing easy wireless announcements.
Additionally, the RT1121 can be programmed to recognize specific DMR codes for selective communication:
- Color Code: Functions like analog QC/DQC codes to filter transmissions.
- Subscriber Unit ID (SU-ID): Identifies individual radios, enabling selective calling.
- Group ID: Determines the call group for message transmission.
For added functionality, the RT1121 includes a relay switch output, which activates when a valid message is received—ideal for triggering external devices such as alarms or strobes. The switch input feature allows integration with door switches or sensors to automatically play a pre-recorded announcement.
Important Notes:
- Indoor Use Only – The RT1121 is designed for protected indoor environments.
- Does Not Drive Speakers Directly – Requires connection to an existing PA system with its own amplifier.
Real-World Application
A customer with three warehouses—only one equipped with a wired PA system—needed a cost-effective way to extend their paging system without running new cables. By installing our Wireless PA System with Speaker in the two additional warehouses and adding a Wireless PA Bridge to the wired PA system, we created a fully integrated communication network. Now, the receptionist can broadcast messages across all warehouses using a single push-to-talk button on their desktop radio.
Designed & Built in the USA
Ideal for warehouses, factories, schools, and large facilities, the Wireless PA Bridge ensures clear, instant, and reliable communication across your entire site—without the need for costly infrastructure upgrades.
Upgrade your facility’s communication with the RT1121—providing reliable, wireless access to your PA system via two-way radios

