N2CKH/R 6 meter Repeater System Configuration

The N2CKH/R 53.430 MHz (-1Mhz) repeater consists of the following components:

We are currently up and running in Phase I of the system plan.

Phase II is currently being configured and tested.

Phase III is planned for completion by late 2001 or early 2002.

In General:

This repeater system is based on a GE Master II Series "M" commercial mobile radio. The GE Master II family of transceivers is a fairly rugged radio from the early 80's that was retired from service. It has been re-crystalled, retuned, and appropriately modified for use as an amateur repeater. The system uses a set of Db Products DB4030 30-54Mhz 4 Cavity duplexers factory tuned for the frequency pair and a Micro Computer Concepts RC-1000 repeater controller.

Phase I of system integration was completed whent he system went on-the-air as N2CKH/R in late April of 2001. Coordination was granted on July 26th, 2001.

Phase II of the system integration with interface the RC-1000 dedicated controller with a rack mounted IBM PC Server 325 266Mhz Pentium Pro having 64MB RAM, two 4.5GB hard drives, CD-ROM, ethernet port with a digital/analog I/O control line interfaced and Soundblaster cards running MS-Windows and custom software written by N2CKH for additional control and signaling capabilities, DX-Cluster voice spots and NOAA EAS/S.A.M.E. severe weather alerting. Additional peripheral equipments will also be implemented.

Phase III of the system integration will swap out the RC-1000 controller for a Link Systems controller and add a 2nd PC Server 325, a 200Mhz unit one 64Mb RAM and one 4.5GB drive and CD-ROM, ethernet port, this one will be running Red Hat Linux v6.2 to act as the node controller for an Internet Repeater Linking Project (IRLP) interface.

The Details:

The repeater's input frequency is 52.430 MHz; its output is 53.430 MHz, and a PL tone of 131.8 Hz is used to activate the repeater as needed due to band conditions. A 131.8 Hz tone will usually be present on the repeater's output at all times. Those without PL who have DTMF capabilities can enter "*320" which will temporarily take the repeater out of PL until 20 seconds of inactivity has elapsed.

N2CKH/R 6 meter Repeater System Technical Specifications

Receiver Specfications

Sensitivity: 0.35 microvolts for 12 dB sinad
Selectivity: front end +/- 1 MHz, IF 12 kHz
Audio level and impedance: 8 Ohm spkr & 600 Ohm 1 V P-
Inter modulation: -80 dB
Squelch sensitivity: 0.2 microvolt open

Transmitter Specifications

Output power: 100 watts nominal.
Spurious & harmonic emission: 85 dBc minimum
Emission type: 16F3
Duty Cycle: continuous duty at rated output power
Maximum deviation: +/- 5 kHz

General Specfications

Frequency stability: +/- 5 PPM at -5 to +55C (+23 to +131F)
Size: 13.5" w x 12.1" d x 4.1" h
Power requirements: 13.8 VDC @ 20 amp max.
Panel: Squelch & Volume, indicators for power, COS, tone & PTT, speaker out, receiver and transmitter antennas, phone line.
Console PTT/Local use PTT Test. PTT Disable. No local mic.

Click here for Exciter/Amplifier details

Click here for Receiver details

Click here for System Duplexer/Antenna/Power Supply details

Click here for photo's and details on the PC Servers

Click here for future enhancement details

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This site is and will always be under construction, since there is always room for improvement.

Entire contents Copyright © 1999-2001 by Stephen B. Hajducek, N2CKH. All Rights Reserved Worldwide.