SR-39-1 Standard Subrack

The SR-39-1 subrack is designed to hold and interconnect the receiver, transmitter and control modules on one universal motherboard. This Type 84 motherboard makes extensive use of cage jacks to interconnect the A and B systems supporting a number of field configurations. Additional auxiliary control connectors provide easy access to virtually all control and audio lines, simplifying many standard base / repeater configurations. Modules may be inserted in the subrack in many various configurations. Receivers and transmitters connect to 48 pin connectors in four slots on the subrack. The A and B sides are shown below.

SR-39-1: 19" Subrack, holds 2 RX Modules, 2 TX (Exciter) Modules, 1 Control Card and 1 System Regulator. SR-39-1 standard features include: Euro-standard metalwork, stainless-steel hardware, fused power connection, transient protectors, gold-plated connectors, and a standard 90-degree, quick-release module-locking system.

 

Please see the PDF technical note to view more information about the SR-39-1 subrack.

 

SR-39-3 Multiple Receiver Subrack

The SR-39-3 subrack is designed to hold and interconnect multiple receivers and control modules on one universal motherboard. The SR-39-3 subrack holds up to five receiver modules and one System Regulator. The system regulator is required for voltage regulation and distribution on the subrack. The multiple receiver subrack is ideal for voting receivers or with the multiple transmitter subrack and multiple power amplifier subrack for multi-channel trunking systems.

The multiple receiver subrack does not interconnect the different receivers but brings control lines and audio out to connection points on the rear of the subrack. The external control connector allows access to the following signals on each receiver:

• Receiver channel select lines
• Receiver Carrier Operated Relay connections (open collector, pull-up resistor or mechanical relay)
• Receiver priority COR output Receiver discriminator or flat / de-emphasis audio output
• Receiver squelch override input
• Receiver signal strength indicator
• Receiver balanced audio output
• Receiver mute input
• Receiver synthesizer lock detect
• Ground

Please see the PDF technical note to view more information about the SR-39-3 Multiple Receiver subrack

 

SR-39-4 Multiple Transmitter Subrack

The SR-39-4 subrack is designed to hold and interconnect multiple transmitters on one universal motherboard. The SR-39-4 subrack holds up to five transmitter modules. The multiple transmitter subrack is ideal for multi-channel trunking systems with the multiple receiver subrack and multiple power amplifier subrack.

The SR-39-4 has a built in voltage regulator mounted behind the blank panel on the right side of the subrack. The multiple transmitter subrack does not interconnect the different transmitters, but brings control lines and audio out to connection points on the rear of the subrack. The external control connector allows access to the following signals on each transmitter:

• Transmitter channel select lines
• Transmitter microphone output
• Transmitter standby
• Transmitter Push To Talk
• Transmitter balanced audio input
• Transmitter squelch flat audio input
• Transmitter squelch de-emphasis input
• Transmitter subtone input 1 and 2
• Transmitter Push To Talk output
• Transmitter direct modulation input
• Ground

Please see the PDF technical note to view more information about the SR-39-4 Multiple Transmitter Subrack.