FM STATION WMIT IS BACK AGAIN

With Interference-free, Solid Coverage of 100,000 Square Miles,
This is the World's Most Powerful Broadcast Station

FLYING down to Charlotte, N. C., last June, an elderly farmer-lady boarded the plane at Washington and took the seat next to me. She held forth on various subjects until: “I suppose you have television up north. We don’t get television where we live, but we have FM. We sure enjoy it too, but we miss WMIT since it quit.”

To that lady, and many thousands of FM listeners in the six-state area that was served by Gordon Gray’s station on Clingman’s Peak, the news that WMIT has gone on the air again has been welcome indeed. The station was closed down in the spring of 1950 for the reason, as Gordon Gray explained then. that he had not had the time to develop it as a commercial enterprise.

Early this year, the property was purchased by a newly-formed group, organized as Mt. Mitchell Broadcasters. Inc.. With headquarters in Charlotte. W. Olin Nesbet, Jr.. a local investment banker, is the president. Vice president is John Erwin, who is also vice president of Allison-Erwin Company, a Charlotte wholesale hardware firm and distributors of Zenith radio sets. W. H. B. Simpson, the secretary and treasurer, operates the Belk-Simpson department store at Greenville, S. C., as well as 17 other Belk stores in the area.

In preparation for getting WMIT back on the air, one of the first steps taken by the new management was to add a 50-kw stage to the original I0-kw transmitter, and to replace the 4-bay antenna with a new one of 8 bays. Now, WMIT has an effective radiated power of 325 kw.

Coverage Area:

As a result, this FM station has a solid coverage area, day and night, of about 100,000 square miles. The most powerful AM station in the coverage area is WBT, Charlotte. Actaually, WBT’s night time pattern is not circular, since the station must go directional to limit interference with KFAB in Lincoln, Nebraska. Listeners in the important industrial city of Gastonia, 18 miles from the transmitter, do not get WBT at night for that reason.

WMIT, by way of contrast, puts an excellent signal into Atlanta, 190 miles away. Experience gained from actual surveys of FM coverage indicates that WMIT is delivering an interference-free signal that will provide full limiting on a well-designed FM receiver with an outdoor antenna at a radius of about 200 miles, reaching an area of some 125,000 square miles. This compares with about 56 square miles for a 250-watt AM station, or 1,200 square miles for a 50-kw. AM station at night.

Thus, a network comprised of AM stations in 70 cities within WMIT’s 50-microvolt contour would cover only a small part of the area served by this single FM station. Total population served by WMIT is over 6,500,000, in the most prosperous part of the south-east, where profits from agriculture have increased greatly in the postwar years, and new industries are continuing to move in steadily. In this section, many people have no local AM program service at all, particularly in the summer, when static is severe. Fort Worth, Texas, for example often fades in and out, but such signals afford little entertainment, and are of no value to listeners who want to know about tomorrow’s weather!

Programs from WMIT:

Operating as a regional station on 106.9 mc., WMIT's programs are tailored strictly to the needs and preferences of the people it serves. The station goes on the air at 6:00 A. M., and closes down at 11:45 P. M. during the week, and at midnight on Saturdays and Sundays. Part of the programs are taken from the Liberty Network, but it is planned to draw on sources in Asheville, Knoxville, Winston-Salem, High Point, Spartanburg, Greenville, and Columbia to maintain a strong local flavor.

The studio at Charlotte is connected to the transmitter by an S-T link. This is a distance of 90 miles. Some programs are recorded from the link for delayed transmission. More than half of the local programs originate at the transmitter, including music on tape and discs, weather reports, announcements, and station breaks. WMIT makes a special feaure of pro-viding the farmers with weather information gathered at Charlotte and Atlanta.

There is a great popular demand for hill-billy music. Very little of it is available from the AM networks and the small independent AM stations have limited libraries. WMIT, however, gearing its program strictly to the needs and preferences of its audience, is carrying about 3 hours of hill-billy songs every day. Also, a substantial amount of time is devoted to excellent programs of a classical and semi-classical nature for the benefit of those who prefer such music.

Setup on the Mountain:

Station WMIT is located on the summit of Clingman's Peak, within easy walking distance of the top of Mt. Mitchell. The latter point is slightly higher, but the 180-ft. tower, added to Clingman’s altitude of 6,557 ft., makes the top beacon light the highest point east of the Mississippi. For FCC purposes, the antenna is calculated to be 3,800 ft. above average terrain.

On pleasant days, several hundred people are likely to visit the station. Starting at Marion, there is a fine state road winding upward to a National Park at the top. Only the last mile is rough going, over a road first cut in 1941 when the station was built.

The first floor of the station is built into solid rock which drops off sharply. It provides living quarters for the staff, and a kitchen and dining room. Getting food up the mountain is not a serious problem for the road is open nearly all the time. Considerable space on the second floor is occupied by the generator room and an adacent drive-in shop. There are additional quarters for the staff, usually totalling 12 in number. The remainder of the second floor is taken up by the transmitter room and studio, both of which open on a broad porch that faces down the valley. Altogether the station has the pleasant. comfortable atmosphere of a mountain-top hotel, and an invitation to be the guest is one, to be accepted with the anticipation of a most pleasant and interesting experience.

Not recommended, however, is a trip down from the summit to Charlotte in the Crosley driven by Chuck Erexson, the photographer who took these pictures. At speeds upward of 60 miles an hour, it can be compared to diving a Piper Cub from an altitude of 20,000 feet!

Transmitter Installation:

The addition of a 50-kw stage to the original 10-kw FM transmitter created two new problems. The diesel engines had been adequate previously, because it was not necessary to step up the 220-volt, 3-phase generators to their full rated power of 75 kva. When that was attempted, it was found impossible because of the high altitude of the installation. While a super-charger might remedy that situation, it was decided to run power lines up the mountain. These will probably be connected by the time this article appears in print.

Also, when the transmitter output was stepped up, trouble developed in the new 8-bay antenna, particularly as a result of rain and sleet. M. H. Sabeff, who is General Electric’s antenna expert, corrected this by replacing the flat plates on the doughnuts with short stubs, and by installing heating elements in the doughnuts. It appears that the WMIT antenna is now the last word as to its ability to handle high power under extreme weather conditions.

The transmitter and studio installation follow conventional practice. For emergency use, a 1-kw REL transmitter is connected to the original 4-bay antenna.

Contrary to some engineering opinion, the REL S-T link from Charlotte to the station has proved highly dependable. It works over a 90-mile hop on 948 mc, with 15 watts output from the transmitter. This equipment, incidentally, has been in use since 1942.

Standard mobile radio units, operating on 26 mc are used as an order circuit between Charlotte and the station. The present antenna, will he changed to a Yagi in order to increase the gain.

According to the operators, everyone wants to know: “How is FM reception on Clingman’s Peak?” Well, that is probably the No. 1 spot for people who like to fish for distant FM stations. Using a standard Zenith receiver and an indoor antenna, it is possible to get a station at practically every channel on the dial. Surprisingly, there seemed to be neither co-channel nor adjacent-channel interference. And there, perhaps, is the answer to people who complain that they can’t get satisfactory FM reception: first, a sensitive receiver, and then enough antenna height to pick up reasonably strong signals. Considering the steady interference-free night-and-day service provided by FM stations, as more and more good FM sets are installed with adequate outdoor antennas, there will be less and less need for short-range AM broadcasting.

The new WMIT installation will be watched closely by FM and AM operators to see whether or not such a project can succeed financially. Certainly, it has many factors in its favor: it is ideally located for an FM station, it has wise programming and enthusiastic management personnel, and last but far from least.. it is FM-only.

If it does meet with success, it may very well provide incentive to others who have been contemplating going into FM but have been disheartened by unfounded stories of FM’s pending demise.

FM-TV, The Journal of Radio Communications/ August 1951, Milton B. Sleeper/Publisher, FM-TV