The long-awaited and much-anticipated upgrade of the K9VI and K9HEP repeaters has finally started. The upgrades involve the 51.91/52.91 6 meter repeater, the 145.33/144.73 2 meter repeater, the 224.700/223.100 222MHz rerpeater, and the pair of UHF repeaters located on site: 443/448.200 and 443/448.475MHz.
The 6 meter repeater utilzes a pair of antennas seperated by approximately 400 feet. The antennas are both located at approximately 450 feet AGL. The repeater consists of a high power Motorola Micor 375 watt base station operating at 250 watts. It is under the control of a CAT 300 repeater controller. The 222MHz repeater is linked to 6 meters and is also under control of the CAT 300. We plan to add a third antenna so that receive diversity can be utilized to improve performance. A LDG RVS-8 voter is on-site for this purpose. It will also be used to vote between a pair of 222MHz antennas and linked, remote receive sites.
The 2 meter repeater is currently a Motorola 125 watt MTR-2000 analog repeater but will soon be upgraded to a 125 watt Quantar with P-25 digital capabilites. It will be linked to the 443.475MHz UHF system full time.
The 443.475 UHF repeater is currently a 25 watt Quantar but will soon be upgraded to a 110 watt Quantar. The 25 watt unit will be configured for switching between 443.200 and 443.475 MHz and will act as a backup unit in the case of failure of either main.
The 443.200 MHz repeater is currently a 110 watts Quantar. It will be linked to the 6m / 222 MHz systems. It will also have IRLP capabilites.
The UHF systems are combined into a single antenna at 475 feet AGL. The combiner utilizes a Celwave 4-port transmitter combiner that has been modified. Two of the 4 ports have circulators and are tuned for the respective transmit frequencies. The other ports do not have circulators and are tuned for the receive frequencies. Each transmit port is fed to a pair of Celwave BpBr cavity filters that have been tuned for a passband at the respective transmit frequency and one notch each at the receive frequencies. Each receive port is fed to a single BpBr cavity that has its notch tuned to 443.375MHz. The resultant notch is equally spaced between each transmitter freqeuncy. The overall result is just under 3dB loss at each port (slightly less on each RX port) and a minimum of 115dB isolation between RX and TX ports. The circulators insure IM is not generated due to the close spacing of the transmitters.
Above the large 4-port combiner is a 6 pole bandpass filter. It is tuned to pass 447 - 450Mhz and is fed from a second UHF antenna at 330 feet AGL. This signal is fed to an amplified multicoupler which, in turn, feeds a pair of AstroTAC UHF receivers. These are intended for use in a voted system to improve mobile performance by reducing multipath effects.
The 222 MHz system is actually a pair of Spectrum Engineering Pty Ltd (Australia) 50 watt repeaters. The are configured as main and alternate main. Both receivers feed the voter and use seperate antennas to, once again, add receive diversity to the system.
In addition, the 222 MHz rack also contains 4 VHF AstroTAC receivers tuned to the National Weather Service on 162.450 (Racine, WI), 162.475 (Rockford, IL), 162.500 (Crystal Lake, IL), and 162.550 (Chicago). The audio from these receviers feeds a Sage ENDEC EAS decoder. Alerts for McHenry, Boone, Lake, Cook, Kane, DuPage, and Winnebago Counties in Illinois and Walworth, Kenosha, Racine, and Milwaukee Counties in WI are rebroadcast through the 6 meter, 222, and 443.200MHz repeaters automatically.
Finally, the non-ham GMRS repeater that I built about 14 years ago has also undergone an upgrade. The old R-100 Motorola repeater has been replaced with a Quantar derated to 50 Watts TPO. The antenna is an 8 bay, open dipole antenna at 200 feet AGL. Thus, the GMRS system is currently operating at maximum allowable power and antenna height. Please drop me an email if you use the system and let me know how the coverage and operation is. Unlimited use of the system has been granted to the LAG group for their public service-related operations. Please drop me an email for permission to utilize the system; a simple note with your GMRS callsign will suffice for my records.
Additional descriptions will be added as work continues on the system.
Click on photos for larger images
1650 Volts 245mA 62% efficiency = 250 Watts
CURRENT SYSTEM STATUS:
443.475 - Fully Operational; Main Antenna / Combiner; Linked to K9VI (224.700 / 52.910)
443.200 - Fully Operational; Main Antenna / Combiner; Stand-alone (P-25 Astro enabled)
145.330 - Fully Operational; Stand-alone; Quantar upgrade complete (P-25 Astro enabled)
224.700 - Operational; Antenna / jumper repaired, system fully functional; linked to 6 meters
52.910 - Fully Operational, Main antenna in duplex use; LNA bypassed Linked to 224.700
144.390 - APRS Digi / Beacon Disabled; Not On-Air at Current Time
NWS / EAS - WX Alerting system upgrade; Crystal Lake, Racine, Rockford, Milwaukee, and
Chicago inputs now in test mode. Alerts to be carried on 52.910, 224.700,
and 443.475 MHz
223.940 MHz - (N9EP) 222MHz System Up, link not yet up (running independant).
224.520 MHz - West Alice, WI: Linking equipment to KA9JPC in construction phase.
224.880 MHz - Schaumburg, IL: System under repair; new permanent location being sought (preferably Chicago southside or West suburbs; to be linked)
467/462.625 - GMRS System Fully Operational; Main Antenna; upgraded to new repeater;
50W at 200 feet with 10dBi gain antenna
Future System Plans:
EAS WX Alerts to be carried on K9VI and linked systems.
443.200 (K9VI) and 145.330 (N9HEP) to be linked for P25 fulltime
224.700 (K9VI system) to be linked full time to 223.94 (Schaumburg, IL)
224.700 (K9VI system) to be linked to 224.520 (West Alice, WI)
224.700 (K9VI system) to have IRLP capability
224.70 (K9VI system) to be linked fulltime to new 224.880 (KB2MAU) system
System Information Summary:
K9VI UHF Repeater: Input 448.200, Output 443.200; PL 131.8 Rx/Tx
K9VI 222MHz Repeater: Input 223.100, Output 224.700; PL 100.0 Rx/Tx (Will change to 110.9)
K9VI 6M Repeater: Input 51.910, Output 52.910; PL 114.8 Rx/Tx
N9HEP VHF Repeater: Input 144.730, Output 145.330; PL 107.2 Rx/Tx
N9HEP UHF Repeater: Input 448.475, Output 443.475; PL 114.8 Rx/Tx
N9EP 222MHz Repeater: Input 222.34, Output 223.94; PL 110.9 Rx/Tx
KB2MAU 222MHZ Repeater: Input 223.28, Output 224.880; PL 110.9 Rx/Tx
KAF1887 GMRS Repeater: Input 467.625, Output 462.625; PL 179.9 (email for use permission)