Wednesday, April 12, 2000

147.30+ Repeater, Wilson NC

147.300+ PL 88.5 HZ

TEARA's WA4UQC 147.30mhz Repeater in Wilson, NC (SK)

'Welcome to the WA4UQC repeater in Wilson, NC. PL 88.5' was the feminine voice of AC4QD heard on this repeater every 10 minutes for over 8 years. It was sponsored by the Triangle East Amateur Radio Association (TEARA). The repeater is now permanently offline, but was much fun for the many years that it was operational. This repeater was located atop the N.C.Special care center on the NorthEast side of Wilson, just off of Hwy 301N. The structure 
is about 130 feet tall, and the repeater/antenna occupied the penthouse area. The repeater's primary antenna was an ANLI A-1000 fed through about 50' of 7/8" Andrews heliax. Wilson is only about 75 feet above sea level, and we were on one of the tallest buildings in town. The repeater room was temperature controlled, and the repeater was powered by a full-time emergency power circuit. The NC Special Care Center rebuilt much of it's upstairs and penthouse area to house loads of new electronic equipment, and all radio operations were required to evacuate the facility to inhibit possible interference from RF exposure.

This picture on the right is the finished product, complete with homebrew duplexers on top. The brown duplexers were originally VHF cavities designed for 1.5 mhz commercial split, and were inappropriate for 2 meter amateur use. The "guts" were removed, new coupling loops and harness built, and away they went. The 3 silver cavities (two are behind the others) were scratch built from aluminum irrigation pipe, using copper pipe for the stubs and copper plate for the end caps. They were originally built as bandpass/band reject cavities from the ARRL handbook, but were later modified for notch only to minimize losses. The repeater was actually a telephone remoted RCA series 1000 transmitter used by the local power and light company to control hot water heaters.

The photo to the left is the repeater with it's cabinet open. Starting from the bottom, there's a Motorola Micor for a UHF remote link, a 30 amp DC supply for the remotes, power distribution panel, telephone remote interface, RCA 1000 RX module, ARR GaAsFet RX preamp, voltage regulation rack, exciter and force cooled PA, and a homebrew "brute force" force-cooled 13 vdc regulator rack. The controller is a MCC RC-1000 with customized firmware. The PA is from a 100 watt VHF GE Mastr II mobile.

Both the link and the primary rx's are tone decode for interference control using Selectone decoders. A pl of 88.5 is required for access, and this pl is also re-encoded on it's output signal during COS activity for linking purposes.

This repeater's primary coverage area was Wilson County, and it was linked full-time to 442.400+ KD4WJD in Zebulon, NC (about 30 miles W) and 147.39+ PL 88.5 WB4IUY in Clayton, NC (about 35 miles SSW).

This next photo is of my oldest son, Chris KF4DBX, installing a copy of the WA4UQC station license to the repeater cabinet. Along with several others, Chris has spent many hours at this repeater site helping with upgrades.

The photo below is a shot from the 147.300's link antenna perch at about 100 feet, looking at it's link antennas awaiting signals to relay. It was taken at nightfall looking into a beautiful NC sunset. In the daytime, the view is quite nice from this site. The large antenna on top is pointed to 147.39 in Clayton, while the smaller antenna below is pointed towards Zebulon. 

Here are a few more pictures of the Wilson repeater.... This picture on the right is the UHF link antenna, 
pointed back towards Zebulon. It provides a passage to the "backbone repeater on 442.400, which in turn provides a common point for other repeaters to "link in".

The photo to the left is the another of the repeater with it's cabinet open. In this  
  picture, Brandon (my younger son) and I were pulling a bit of _MAJOR_ maintenance on the repeater. Over the years, it has been hit by lightning 3 times... once destroying the controller, once blowing a large DC Power Supply, and lastly blowing the processor chip in the controller and the main VHF power amplifier. Since 1993, it has had 3 power amplifiers, and a variety of other little things replaced. The main antenna has been destroyed twice by lightning, as well as destroying the feedline on one ocasion. This type of maintenance isn't abnormal, and isn't too bad considering that it runs 24 hours a day, 7 days a week.

The next photo on the right is of the repeater when is was getting an overhaul
about a year ago. It was hit by lightning in a spring storm, and received a bit of damage to the VHF power amp, duplexers, antenna, phone patch, and controller. Steve KD4WIW, my son Brandon, and I spent a couple of days trying to sort through the wreckage, hihi!

The photo below is a shot from the 147.300's rooftop, as seen when looking eastward.