442.425

442.425 Repeater - Republic, MO

On-Air Date:                     September 2006

Repeater Transmit:         442.425

Repeater Receive:           447.425               (+5.0 MHz)

Modes:                               Analog or P25 Digital

PL Tone:                             162.2 Hz

PL Direction:                      Encode & Decode

P25 NAC                             656

Bandwidth:                        Wideband – 25 kHz

Transmit Power:               100-Watts

Antenna System:              Sinclair SD314-HF2P2SNM(D02)  - 315' AGL

Link antennas:                   N/A

Coax Cable:                        Commscope LDF7-50 1-5/8" Heliax

Controller:                         SCOM 7330

Repeater                            Motorola Quantar

Duplexer:                            TX RX 28-66-02A

Link Radios:                       N/A

Backup power:                  Site Generator

Router:                               Ubiquiti Edgerouter X

Internet:                             Yes - Springnet

Nets:                                   Mondays @ 7:00 p.m. - Polk County Amateur Radio (PCAR) (similar to ARES)

                                             Thursdays @ 7:30 p.m.  - Nixa ARC Check-in Net

                                             Fridays @ 7:30 p.m. - Region D ARES VHF Net

The 442.425 was the third repeater placed online by the Nixa ARC.  Originally, the repeater was installed at the residence of Rich Vogt, KB9YZE, in NE Nixa with tower work being done by Allen Busiek, WF5U. The repeater was a Motorola R1225 operating on 444.275 MHz with the callsign of KC0LUN until July 2011 when the callsign was changed to K0NXA.  In March 2007, James Adkins, KB0NHX, John Copelin, KC0QNM, Chris Cochran, KB0WZC and Jeremy Tannehill, KC0UJZ, installed the DB-408 antenna atop Cox South Hospital (same day as the 224.280 install) and the repeater was placed into service. Unfortunately, an STL that shot through Cox South caused interference so a new frequency was sought.  The repeater was then moved to 442.275 MHz on January 1, 2009 and remained on that frequency for some time.  However, due to some linking of the 147.225 to the SkyWarn network, issues arose and the only way to mitigate it without purchasing filters and spending lots of time investigating was yet another frequency change!   On August 20, 2013,  the repeater moved to 442.425 MHz and has stayed there since. 

When the 224.280 repeater was changed out, we also installed a pair of Motorola CDM mobile radios for the 442.425 repeater and added a 200-W Henry amplifier with DLS-75 power supply.  With time, the amplifier failed - this time it wasn't a component but a compromised circuit board!  When the repeater moved to the Christian County 911 tower on May 6, 2017, a Motorola MSF-5000 225-Watt High Power repeater was installed.  The repeater, previously a UHF paging transmitter, was donated to the club by Cox Hospital and moved to amateur radio service by James Adkins, KB0NHX.  When the system developed an intermittent PL tone encode problem in 2020, Todd Christell, AD0RR, volunteered to re-cap the repeater which resolved all of our problems. 

The 442.425 repeater was the home of the club's first IRLP node #3995.  This node linked us to the Central Region Intertie System (CRIS) which covered most of West Central Missouri and the KC Metro as well as NW Missouri into Nebraska at its peak.  Computer problems and lack of anyone knowledgeable or willing to learn IRLP lead to its demise.  In June 2022, All Star Node #565500 was installed.  The All Star node also allowed us to add EchoLink node K0NXA-L.  With IRLP gone, All Star would be the new method to link the SMLRS to the Nixa ARC Linked Repeater System.  The 442.425 is the hub repeater that links the 145.270, 224.280 and 53.270 Nixa ARC linked repeater system together for the nets on Thursday nights and is the backup "South Hub" for the SMLRS should the Crane repeater fail or the system need to be broken apart for special events.

On July 1, 2023, the 442.425 repeater was moved off the Christian County 911 tower in Clever and placed online from the City Utilities tower in Republic.  The Christian County 911 cancelled the club’s 99 year lease after 6 years giving us until September 2023 to have all our equipment removed from the tower so they would have room for a new 700 MHz trunked radio system site.  The Sinclair SD314-HF2P2SNM(D02) had previously been purchased from Jim, W7RY, when he removed his 444.050 repeater from service in Nixa after only one year of operation.  This antenna would replace the DB-420 we had installed at Clever.  Special thanks to Jeff Bertholdi, W0AV, for his help arranging for the 442.425 to be moved to the Republic site.

In July 2025, the High Power Motorola MSF-5000 failed and was upgraded to an analog and P25 capable Motorola Quantar with 100-Watts output power.