Tag Archives: Glenn (W7GSW)

Proper QRO: K4RLC Tours The Edward R. Murrow Transmitting Station

Many thank to Bob (K4RLC) who shares the following guest post:

Visiting VOA Site B: The Edward R. Murrow Transmitting Station

by Bob (K4RLC)

Two week sago, Dale (W4AUV) and I were treated to a “under the hood” visit to the last remaining Voice of America transmitting station in the United States. It is located in eastern North Carolina, and officially known as the “Edward R. Murrow Transmitting Station” part of the “Office of Cuba Broadcasting” in Grimesland, North Carolina. Also, known as “VOA Site B.” This type of shortwave broadcast station is only one of a few remaining worldwide.

[Note: Click on images to enlarge.]

VOA QSL Card showing some of the 38 antennas

This VOA site has been on the air continuously (24/7/365)  since the 1963 on-site dedication by President John Kennedy, broadcasting up 8 transmitters at a time on the short wave bands. There are three 250,000 watt and five 500,000 watt GE, Continental and Telefunken  transmitters feeding 38 possible antenna configurations, with an Effective Radiated Power of 2,000,000 watts. (There is also a 39th antenna, that is a Dummy Load that will handle 500,000 watts).

The antenna field covers over 6,000 acres of flat, costal plain wetlands, not far from the  Atlantic Ocean, so it has a minimal absorption factor and a salt water boost.

Front of VOA Edward R. Murrow Transmitting Station
Wall plaque in lobby explaining the legacy of Edward R. Murrow, who became known while a CBS Radio correspondent in London, broadcasting during the “Blitz” the infamous bombing of London by the Nazis during WW2 (click image to enlarge)
TCI “Curtain” antenna made of 4 dipoles wide & 6 dipoles high, pointed at Cuba. It is controllable in both vertical and horizontal azimuth, depending on the configuration has to up 23dB gain at a 4 degree take off angle

The antennas are fed by over 26 miles of 300 Ohm open line “ladder line” with a minimal SWR and minimal signal loss. The largest antennas are called “Curtain” antennas, given their configuration, of matched horizonal and vertical dipoles suspended between large towers, giving the visual impression of huge curtains.

There are also  rhombics, each 6 wave lengths long. The rhombics are not used as often, given their narrow bandwidth and narrow beamwidth. The Curtains can bathe a large geographic area (such as part of a continent) with a very strong signal. The primary broadcast areas for this station are Cuba, Central and South America, and Africa (although the antennas could reach out and touch Russia and eastern Europe, when needed).

Curtain and Rhombic antennas fed from the antenna switching center
Glenn showing Dale features of the GB-6 transmitter console in the large 8 transmitter control bay
GB-6 Transmitter Monitor & switches
The antennas are well constructed & fed with minimal-loss  open feed line. Note SWR of 1.1:1 at 75,000 watts !
Glenn & Dale studying the transmitter output in the main control room complex
Larger control panel for each transmitter. Note image of “Casper the Friendly Ghost” over the meters for GB-7: There are current problems with the transmitter and, in technical terms, “it’s spooked” !
Antenna switch controller for matching the 8 transmitters with 38 antenna configs.

Glenn & Dale examining the open feedline from Switching station to antenna field; 8 inch coax to Switching station

Many of the engineers are hams, including Macon (WB4PMQ), the chief engineer. Gary (N2AD) transferred to Greenville when the VOA in Bethany, Ohio closed. (The Bethany VOA site operated during WW2 into Germany, and was referred as the “Ohio Liars” by Hilter !)

Glenn (W7GSW), a US Navy communications vet, has been at the site many years and conducted much of the tour for Dale and I. Continue reading Proper QRO: K4RLC Tours The Edward R. Murrow Transmitting Station