Marshall County is fairly rural and lacked full APRS coverage. KC9QAK in Bourbon and N9GPY in Culver covered the southern part of the county, but left a gap in coverage to the north. Our goal was to fill in the coverage area in northern Marshall County.
After researching options for APRS data handling, we choose the WX3IN1 Digipeater from Microsat. The WX3IN1 device connects directly to the internet and supports digipeating, beaconing, and messaging. It supports our Davis Vantage 2 weather station and has web-based configuration for easy setup.
For the RF side, we opted for the Kenwood TM-281A 2M tranceiver. The Kenwood is very well heat-sinked, requires no fans, and will provide 65W of power if needed. Since the digipeater operates at low power, we should never stress the radio.
It is powered by a Radio Shack 22-510 25W 12V switching power supply. I believe the supply is actually made by Samlec. It provides enough power to run the WX3IN1 device and the radio.
The equipment is powered through an APC UPS and the entire system is backed-up by a 9kw gas-fueled generator.
W9LRT-1, the Bremen digipeater site, uses a discone antenna at 25 feet. The antenna has no transmit gain, but receives very well, making it ideal for APRS. A side benefit has been an upward tilt in our reception pattern. This allows us to 'capture' traffic from balloon launches in all directions. We have tracked balloons as far away as Peoria, Illinois and Defiance, Ohio. The Bremen site beacons position data for the W9LRT Repeater in Bremen, the K9WZ Repeater in Plymouth, and Community Hospital of Bremen.
W9LRT-2, located in Warsaw, uses a Diamond X-510 antenna at 100 feet. This digipeater has a wide reception area and provides stable service to the National Weather Service office in North Webster. The Warsaw site beacons position data for the K9DEW Repeaters in Warsaw and Warsaw Community Hospital.
To see a map of APRS traffic in our area, click here!
We have had requests for the wiring diagram to connect the Microsat and Kenwood TM-281a. It can be found here!