Sierra Radio Systems Coax Cables are pre-terminated, 6-foot lengths of LMR-195 with a BNC Male on one end and a PL-259 on the other. The cable is ready to use with the Sierra Radio Systems Coax Switch module.

• Cable Length: 6 ft.

• Cable Type: LMR-195

• Coaxial Connectors: (1) BNC male, and (1) PL-259

Sierra Radio Systems Station Controllers

APPLICATIONS: RADIO SITE MONITORING AND CONTROL

Managing critical assets at remote sites is difficult, time consuming and expensive. Knowing the current health, or even more important, the status of equipment that is degraded or has failed is critical. You can easily spend a whole day just getting to a remote site. Wouldn't it be great if you knew before you left what the failure was? Did the power supply fail? Did the PA on the transmitter fail? Did the antenna system fail? When a remote radio installation is degraded or off the air, it's hard to know what the problem is. Even better, it would be great to get an early warning when things start to fail.

SRS Station Controllers can tell you the current state of your critical assets including repeater systems, wireless internet systems, solar power and battery systems, HVAC units, door security, RF power and other critical measurements. You can also remotely actuate relays to change the site's configuration or turn equipment on and off.

STATION MONITORING AND CONTROL

In today's modern radio room, you typically have several radios, antennas, power systems, amplifier and other radio accessories. A station controller lets you centralize the control and monitoring of this equipment. The control point could be a physical button panel at the operating position, a soft panel on a PC screen, a scheduled event or remotely controlled over the internet. At the flick of a button, your entire station comes to life, you can switch radios and antennas or turn specific equipment on and off. You can also monitor critical station status including AC power on/off, DV voltages, RF power, etc.

ARCHITECTURE: HARDWARE

The SRS Station Controller is a module hardware architecture. You can customize your system to meet your needs and grow as your needs change. The form factor is a set of board called "modules" that can be mounted in a chassis box, rack mount chassis or mounted to DIN rails on a typical "telco wall" type of configuration. This DIN rail mounting is commonly found in industrial automation applications.

The modular architecture allows you to build up your system over time by adding the modules you need. You can mix and match any combination of available modules or even design your own.

At a minimum, the system would consist of a host PC, typically a Raspberry Pi, but you can use any computer with a USB port that can run Node Red and at least one control module. This module can be the GPIO module, coax switch, RF watt meter, etc. Every module has it's own network address making it easy to have multiple modules of the same type on the network.

SOFTWARE

The master control processor is a Raspberry Pi running Raspberry PI OS. We provide a Node Red flow which serves as the main dashboard and control panel. the communications protocol is published to allow you to develop your own applications in any programming language you like or use one of our sample applications written in Node Red or Python.

DCN - Device Control Network

At the heart of the Sierra Radio Station Controller is the DCN. The DCN, Device Control Network, is the communications medium that allows all the modules to communicate. The DCN is a combination of physical communications medium and the command structure that runs on top of that medium.

Physical Communications Medium

All SRS SC modules include RJ45 jacks to connect modules in a network. These are not ethernet connections but our own communications protocol. We use RS-485 multi-drop serial wiring over CAT5 cable in addition to 12-volt power and ground. This makes it very easy to add modules to the system. Just plug in a CAT5 or better ethernet cable between modules and you are providing both power and data. One significant advantage to using RS-485 is the ability to transmit data over several hundred and even thousands of feet allowing you to remotely locate modules and still provide power and data in a single, inexpensive cable.

Various data radio modules are available to transmit the DCN data over the air between nodes on the network. Currently we can provide boards that support the Haltec Meshtastic LoRa v3 modules as well as proprietary non-Meshtastic LoRa radio modules for reduced latency.

DCN Software Protocol

Although the protocol is not an industry standard, the command structure and protocol is published so that others can design and build their own modules and systems. The communications data format is a simple ASCII text field sent "in the clear". Data encryption can be added as needed for over the air control systems. The packet format includes a from/to address scheme, payload and framing characters. Advanced users can even monitor and insert traffic on the control network with a simple dumb terminal program like Putty and a USB / DCN dongle.