CERA

COLUMBIA EMERGENCY REPEATER ASSOCIATION

The desire of a repeater on the WUND-TV tower began with Mike Cohoon, KB4TOH, and other interested hams from throughout eastern North Carolina. After several years of seeking permission, the repeater was installed and went on air the weekend of July 4, 1989. The first meeting of the Columbia Emergency Repeater Association was held at the Columbia Fire House on February 10, 1990. The first officers elected were: President, Mike Cohoon, KB4TOH; Vice President, Albert Onley, K4VHV; Secretary-Treasurer, Greg Terranova, N4QLD. The group voted to air the Albemarle Emergency Repeater Net, now named the Coastal Emergency Linking Net, at 9:00 on Wednesday nights on the Columbia Repeater. The net covered a wide area of northeastern North Carolina and into southeastern Virginia. A linking backbone with Columbia UHF and Williamston UHF created a linking network of Columbia; Williamston; Manteo; Rocky Mount; Ahoskie; Rich Square; Elizabeth City; Hatteras; Franklin, VA; Farmville; Delco; Greenville; and Hertford. It took several years for the linking process to take place and several of the repeaters have since dropped out of the system. Seven repeaters, linked together in a UHF circuit, currently remain in the system and provide valuable communication when the usual means of communication fail. Several unlinked repeaters are also considered part of the Eastern Carolina emergency network.

OFFICERS FOR 2021

KD4CEB

Kerry Krauss

President

E-mail

(252) 336-4418

KB4TOH

Mike Cohoon

Vice President

E-mail

(252) 793-3009

KC4PTA

Jo Ann Tetterton

Secretary/Treasurer

E-mail

(252) 926-9944

AK4TW

Dean Patsel

Director at Large

E-mail

(252) 333-7402

WB1CZX

Tom Ponte

Director at Large

E-mail

(252) 426-7145

N4ACT

Jim Bailey

Director at Large

E-mail

(252) 480-3065

MEETING SCHEDULE
Quarterly meetings are held in February, May, August, and November on the second Saturday starting at 10:30 AM at the Golden Skillet Restaurant in Plymouth, NC, unless otherwise announced. ARES occupies the first half of the meeting, which is followed by lunch. CERA business will be conducted after lunch. For current information or changes, check for announcements on the Coastal Emergency Linking Net on Wednesday at 9:00 PM, or call Kerry Krauss or Jo Ann Tetterton at the numbers above.

TOWER INFO

The original KB4TOH (now KX4NC) repeater went on the air July 4th weekend, 1989, on a frequency of 145.110 MHz. The original repeater was a GE Mastr Pro, later upgraded to ICOM in August 1991. After years of upgrades and work we finally moved to our new location on the tower. On November 1, 2008, the repeater call was changed from KB4TOH to KX4NC to reflect CERA's ownership of the repeater system. The repeater trustee is Mike Cohoon, KB4TOH.

The VHF and UHF repeaters and an APRS node are located at 1,200 feet in a weatherproof enclosure on a platform on the WUND tower in Columbia.

Repeater coordinates are Lat 35°53'59" Lon -76°20'52"

REPEATER INFO

VHF Repeater: Kenwood TKR 750 (Second unit down)

Transmit: 146.835 MHz

Antenna: Sinclair 210 @ 1150' fed with 75' of 7/8" hard line

ERP: 200W

Receive: 146.235 MHz

Antenna: Sinclair 210 @ 1280' fed with 95' of 7/8" hard line

Controller: Linkcom RLC3 located in ground shelter

Mobile Coverage: 60 to 80 miles, including Hatteras, New Bern, Farmville, Tarboro, Gates County, Elizabeth City, Currituck County, Southern Virginia and Dare County, and Okrakoke.

UHF Repeater: Kenwood TKR 820 (Third unit down)

Transmit/Recieve 443.300/ 448.300 MHz

Feed line: 15' of RG-214 from duplexer

Antenna: Andrew DB420

ERP: 80W

Controller: Same as VHF above

Mobile Coverage: about 65 miles and serves the same areas as the VHF repeater.

LINKING MAP & INFORMATION

[To the left] is the most recently approved linking map and a table containing the same information as seen on the map. Below that table is a description of how the system works and an example of how to use it. Any licensed amateur may use the system but please be courteous and give priority to the net if it is active, especially during emergency operation.

Callsign

Location

Frequencies

DTMF Up

DTMF Down

KX4NC

Columbia

146.835 / 443.300

11

10

WA4VTX

Hertford

147.330 / 444.300

331

330

WB4YNF

Ahoskie

145.130 / 444.200

131

130

K4OBX

Engelhard

146.715

71

70

K4OBX

Hatteras

145.150

151

150

K4BCH

Bath

146.955

951

950

K4SER

Williamston

145.410

41

40

W4GDF

Greenville

147.090

91

90

The linking system is rather straightforward in how it operates. The KX4NC Columbia UHF (443.300) repeater and antenna live on the WUND-TV tower at 1,200 feet. This provides an effective range of ~65 miles from the tower site and by itself is a great repeater but is also the backbone for the linking system. Repeaters that are in the system can be linked to the backbone with the appropriate DTMF codes. All repeaters that are linked to the backbone essentially become one large network that passes traffic from any one of the linked repeaters through the backbone and out to all other linked repeaters.

The details of what is going on behind the scenes are each repeater has a dedicated link radio that is on the Columbia UHF frequency. When we, for example, are using the K4OBX Hatteras repeater we can enter DTMF 151 and this will cause the Hatteras repeater to activate its link radio and respond with some audio confirmation after you unkey. Hatteras is now patched into the Columbia UHF backbone. Any transmissions on the Hatteras repeater will also be heard on Columbia UHF and vice-versa. Now let's say we want to contact someone who may be listening to the Greenville repeater. We can enter DTMF code 91 and this code will be heard by the Hatteras repeater, be sent out by its link radio, go through the Columbia UHF backbone, and be heard by the Greenville link radio which will cause the Greenville repeater to activate and join the fun. Now any traffic that goes into Greenville, Columbia UHF, or Hatteras will go through the Columbia backbone and in turn be heard on all three repeaters.

As mentioned before any licensed amateur radio operator is welcome to use the system. Just please be courteous and bring any links down that you have brought up. The way to do this is by entering the DTMF down codes for each repeater you brought up but in reverse order. For our Hatteras example above, best practice would be to announce your callsign followed by "bringing down the links" followed by DTMF 90 and unkey your radio. Listen for Greenville to confirm it has come down and key up to enter DTMF 150 to bring down the Hatteras link which after unkeying you should hear Hatteras confirm its link is down.

Linking to Columbia VHF (146.835) works in the same way as other repeaters on the system, if we wanted to include Columbia VHF in our Hatteras example above, we would enter DTMF 11 after Hatteras is linked to the backbone. The Columbia UHF backbone would hear this and link in the Columbia VHF repeater. Just be sure to bring this down as you would with any other link before your local repeater is disconnected from the backbone.

APRS NODE

APRS Node Link

BECOMING A MEMBER

 Joining CERA is pretty easy! You have the option of either attending a quarterly meeting to fill out an application form and pay the dues there or you can print the form linked below, fill it out, and mail it in with a check or money order. The dues are $25.00 yearly for the member and immediate family.

Both of the following forms are identical as far as content. the PDF version can only be viewed and printed while the Microsoft Word Document version can be edited with your information before printing. If you are unsure which to download just get the PDF version.

[Webmaster's Note: The files were no longer available at the time of this writing.  Please contact Jo Ann KC4PTA for information on joining CERA]

NET SCRIPT

Two versions of the net script are provided for your convenience. One is in the form of a PDF document that cannot be edited, only viewed and printed out. The second is in the form of a Microsoft Word document (.docx) both are identical as far as content. You can edit the word document to insert information such as your callsign, name, location, etc. before printing. Any place in the script you see square brackets [Like This] with bold text is an indication of an instruction or for you to fill in the blank with your own information. If you are unsure which to download just get the PDF version.

[Webmaster's Note: Only the PDF version was available at the time of this writing.  Please contact Jo Ann KC4PTA if you need the Microsoft Word (.docx) version]

CERA Net Script (PDF)