Washington State Department of Natural Resources

Questions? ... Comments? ... Rob Lee, DNR Radio Operations, Olympia

Grass Mountain - Greenwater Repeater Site
Before and After Building Interior Images

Before: 9-24-2003

The images above show the installation of a new cable runway and the relocation of a second runway along with a new equipment rack and battery back-up (located in the white container just above floor level). To conform with Motorola R-56 communications site standards, new grounding was installed and lightning protection was added at the antenna coaxial cable entrance panel. The existing radio equipment was transferred from a cabinet style enclosure to the newly installed rack assembly and reprogrammed via PC to accommodate the battery back-up configuration. The large gap between the currently installed equipment and the battery back-up near the floor will be used to mount microwave equipment that will be linked to the region office. Site monitoring equipment may also occupy a portion of this space. The monitoring equipment will be used to remotely monitor items such as commercial/generator power activity, equipment alarms, building activity (doors open), etc.



The image to the left is a closer look at the installation from the rear. The Star Trek multi-cylindrical looking device is a transmitter-receiver duplexer or just "duplexer" for short. It's primary purpose is to enable the repeater station to transmit and receive on the same antenna at the same time. The unit below the duplexer is the Motorola Quantar Greenwater repeater. The Quantar is a micro-processor controlled unit that boots up in a fashion similar to a PC. It does have a couple mechanical adjustments as would be found in radios from the pre-microprocessor era, otherwise, it relies totally upon a PC interface for programming functions. Some of the common means used to interface with the Quantar include Ethernet, modem and direct cable connection. 



The images above show a closer look of our current battery back-up configuration. The Motorola Quantars, used by the agency, are designed to operate from a 24 VDC battery back-up source. The image on the left shows two 12 VDC communication site batteries wired in series to provide the necessary voltage. The image on the right shows the package in it's normal configuration with the seismic restraint in place. The primary purpose of the battery back-up is to provide a seamless transition between commercial AC power and generator AC power at the site and greatly reduce the possibility on an unexpected reboot of the system in the same manner a UPS protects a desktop PC. The battery back-up will also provide a limited amount of repeater operation in the event both commercial and generator power fail. In this situation the transmit power of the repeater is programmed to be reduced from 80 watts to 20 watts to extend battery life. An audible "beep" will periodically be heard when the repeater is on the air to alert users that the system is operating on battery only.

No ... 
This is not part of a Homer Simpson look alike contest. The pest control folks were also paying a visit to the radio site building  the same day we were doing our initial survey.

Before? ... After? ... The Red Blue Show? ...

Grass Mountain - Current Status Highlights (Interior) 10-6-2003



Installation of new cable runway.

Relocation of second cable runway.

Installation of equipment rack.

Revision and upgrade of equipment rack interior ground system to meet R-56 standards.

Installation of lightning protection device and associated wiring at building coaxial cable entrance panel.

Relocation of radio equipment from cabinet mounting to equipment rack mounting including necessary cabling revisions.

Installation of battery back-up system and associated PC programming.

PC programming during  transition to the new narrowband analog - digital capable radio system.

No items pending

Questions? ... Comments? ... Rob Lee, DNR Radio Operations, Olympia
Information updated: 01-16-05