Tower - Antenna - Transmitter

This page tells about important items located at the tower site to make transmission of the KYFC-TV signal possible along with some stories about some of the issues faced while doing the installation.

Tower Assembly

Tall television towers are not shipped to the site in one piece. In fact, KYFC-TV’s tower came in thousands of pieces consisting of legs made out of 6 inch diameter steel pipe and steel rods for cross members. The tower that was purchased was fabricated by Stainless, Inc., a reputable tower manufacturer. In case you are wondering, the tower is not made of stainless steel. It is made of galvanized steel. The galvanizing prevents rust. It was shipped to Kansas City in a gondola type rail car and sat at a rail siding to be unloaded and brought to the tower site by a tower crew experienced in tower unloading, assembling the pieces and stacking it into a tall structure. The photo to the right shows the assembled tower sections. These sections are painted on the ground with the color required by the FAA for aeronautical navigation marking. Once painted and dry these 30 foot sections are ready to be stacked to make up the 1000 foot tower.

Dr. Al’s granddaughter, Liane Lewis is shown climbing on one of the sections prior to lifting.

Tower Foundation

The physical construction of a tall tower supported by guy wires begins with a solid foundation. For the new KYFC-TV tower the foundation consisted of a concrete column extending to bedrock. This would bear the weight of the antenna, tower steel and the pull down force due to the pulling of the guy wires that hold tower up. There would be 6 guy wire levels somewhat evenly spaced in height on the 1000 foot tower. The guy wires would be connected to anchors placed in the ground. These anchors would resist the pulling up of the guy wires on the tower. The tower had a total of 6 concrete anchor points where the guy wires were attached. The satellite image below shows the tower location, marked with a red X and each anchor point A thru C.

The anchor holes were all dug by hand with the exception of B-1. These excavations were holes about 12 feet long  x 12 feet wide and 12 feet deep. They were dug by KCYFC staff using a backhoe, picks and shovels. Anchor B-1 and the tower center, marked by the red X, were drilled columns about 3 foot in diameter.

I will relate one story about the drilled anchor B-1. We had originally planned on digging a hole similar to the other anchors. We, however, hit a shelf of very hard rock and were unable to dig down more than a few feet. Borings showed the rock being fairly massive and wide spread. After consultation with a geotechnical engineer it was decided boring through the rock and anchoring the concrete to the bedrock would work. We had a large rock boring machine come in and drill a hole 3 feet in diameter. After placing the necessary reinforcement rods we began to fill the hole with concrete. I can’t recall how many trucks of concrete came, but there were a lot. The superintendent for the job was Bob Armstrong who was hired by KCYFC to oversee the construction of studio and transmitter site. Bob was a super nice guy and a well experienced contractor. After a long day of pouring concrete Bob reached up to his ear only to discover his hearing aid was gone! He then figured out what happened to it. Many years from now someone will excavate in that area and dig out the old anchor foundation only to find this strange electronic device encased in the concrete near the bottom. :)

Tower Stacking

September 25, 1978 was an exciting day for KYFC-TV. It was a day that the first section of tower was stood up. The photo on the right shows a crane setting that first section on the concrete pier that goes about 30 feet down to bedrock. The first one hundred feet of tower can be set with a crane. After that the reach is too far for a crane. The tower erectors will then switch to a gin pole. A gin pole is a steel lattice structure that is around 50 feet high with a pulley on top (called a rooster head). It is temporarily attached to the tower and extends above the top. The illustration to the far right shows a gin pole attached to a tower lifting a tower section (in blue).

A heavy cable from the rooster head will pick up another tower section and the workers will bolt it onto the tower. This continues in a leap frog fashion until they arrive at the point where a guy wire is to be placed. They then attach 3 guy cables spaced by 120 degrees and stretch each out to its respective anchor point. They must do this, otherwise the tower would topple without the guy wires providing the rigidity needed. After the guy wires are attached and tensioned stacking continues until they reach the next point where guy wires need to be attached or until the tower is at its full height.

Of course, weather can impact the ability to work on the tower. I recall being at the tower site one day when a thunderstorm began to roll in. Needless to say, the tower workers will typically evacuate the tower to avoid being on it should it get struck by lightning. I could hear thunder and our crew was scrambling to get off the tower. They were just about off the tower when I noticed the hair on one of the workers standing straight up. That meant there was a lot of static electricity present with a possible lightning strike eminent. Thankfully, all of the crew was able to get off the tower in time.

There was another time that I was working in the transmitter room when a T-Storm rolled through. I was working with our in-house electrician Richard Volts (yes that was his name. He was the nicest person you would ever want to meet and a very talented electrician). All of a sudden lightning struck the tower. It caused a rather bright blue flash and a loud snap at the wall where the lines come through the building from the tower. Needless to say, Richard and I stayed away from that part of the building until the storm blew by.

Antenna

The antenna is mounted on top of the tower and transmits the KYFC-TV signal out to the viewers. This antenna is large and weighs almost 3,000 pounds! It is large because it must handle the power fed into it to transmit the 1 million Watts of power. The combination of height and power makes it possible for the signal to reach out about 55 miles. The sales brochure at the right shows the antenna specifications. For those that are technically inclined you can click the brochure to see an enlargement on a separate page.

Note that the antenna photo in the picture is the KYFC-TV antenna being set in place. The manufacturer asked if they could use a photo of the tower for the brochure to be sent out to all broadcasters interested in this type of antenna. The company hired a helicopter and photographer to take the photo.

The photo below the sales brochure is an enlargement of the photo. You will notice that there are 3 workers in the air. One is standing on the top plate of the tower to line up the holes for the bolts to attach the antenna pole to the tower. One worker is on the antenna while the third worker is on the gin pole to the top and left of the antenna. This is definitely not work for the faint of heart. It is dangerous work and requires skill in maneuvering massive items weighing thousands of pounds while strapped to a tower with a belt.

After the antenna is set in place the next task for the tower workers is the installation of the transmission line. This line connects between the the transmitter and the antenna. It looks like a 6 inch copper water line. This line carries the high power radio frequency energy on channel 50 from the output of the transmitter to the antenna and broadcasts it to the viewers at home. This line comes in 20 foot sections and must be bolted together. It is then pressurized with dry nitrogen gas to keep moisture from getting into the line. Moisture could cause arcing and resulting in the line burning up. The author has seen this happen and it is not only messy but it is time consuming to replace as well as expensive.  

Topping Off

The topping off (i.e. antenna mounted on top of the tower) is a joyous occasion for any TV station. The photo below on the right was taken by same helicopter photographer that did the photo for the antenna manufacture. In the photo the tower crew is close to finishing up the mounting. This photo was taken looking to the northeast. Old Arrowhead stadium can be seen in the upper right corner.

The photo below on the right is a ground view looking up at the completed tower. The guy wires are visible going out from the tower. You can also see the microwave antenna in this photo. It is shown as the small dark dot on the left towards the top of the tower. This antenna receives the audio and video signals from the KYFC-TV studio and sends them into the high power transmitter.

Above is top view looking down the tower. The tower worker that took this photo is standing on climbing rungs near the top of the antenna. The white rectangle to the right is the roof of the building. The road entering from 56th Street is at the top.  

This is a photo of the base of the tower. The tower is 50 feet from the building.

Return to the KYFC-TV home page

© 2023 Joe Snelson

Transmitter Building

The building at the transmitter served multiple purposes. First, its primary purpose was to house the KFYC-TV transmitter. However, that took up only a very small part at the west end of the building nearest the tower. At the same end of the building was living quarters. This “apartment” was constructed to provide lodging for a security person. This individual might be a student of the Christ Unlimited Bible Institute or a single full time staff member. Their presence would provide security at night to thwart off burglars and vandals.

The remainder of this large building was used as storage for scenery, props and other large items used for rallies and other KCYFC activities.

This building, similar to the studio building, was made of pre-cast concrete walls and roof. Staff members along with volunteers dug and poured the concrete footings to support the pre-cast structure. Even Dr. Al got into the activities. He came out many times to operate the backhoe, set rebar and help pour concrete. He knew how to roll up his sleeves and go to work which served as an inspiration to all that were there. An outside contractor was contracted to do the setting of the pre-cast concrete since this was highly specialized work and required the use of a large industrial construction crane.

I remember riding with Dr. Al out to the transmitter site one evening. We stopped at Winstead’s along the way and grabbed a hamburger. When we got to the tower site I mapped out a path that needed to be cleared to accommodate Kansas City Power and Light setting poles between a power pole on 56th Street to where the building would be. Dr. Al hopped up on a bulldozer and began to clear the brush and trees for the path. We worked till dark.

Overall KCYFC was able to save significant dollars by doing a lot of the work with staff and volunteers.

Transmitter

Audio and video signals emanating from the studio are transported to the transmitter site over a private microwave radio link. When the signals arrive at the transmitter they are sent into a high powered transmitter where they are converted to a radio frequency on channel 50 and amplified to a very high power using a tube called a klystron. Then transmitter requires a high voltage, 25,000 Volts, to amplify the signal. This generates a lot of heat and uses water circulating through the tubes to keep them cool. The amplified signal is sent up the tower using coax line. This is not your typical coax cable that connects to your TV set. Due to the high power involved the coax line is made of 6 inch copper. It looks like a “gi-huge-ee” (a term Dr. Al sometimes used to describe big) water pipe.

The author will relate a story regarding the transmitter. It was mentioned that the Klystron tubes required 25,000 Volts. This was obtained from a large power supply unit that set outside the building. The components in the supply are submerged in mineral oil. I got a call one morning that the station was off the air. I went to the transmitter site and determined that a component inside the supply was defective and needed to be replaced. What hasn’t yet been mentioned is that it was winter time. So, I proceeded to go outside and unbolt the access cover so I could remove the component. I had to reach into the supply with oil up to up to my elbows with a temperature of about 32 degrees Fahrenheit! That was an invigorating experience to say the least.

East side of the building. The large metal door to the right of the trailer allowed trucks to drive inside.

West side of the building. The metal grating going from the tower to the building enters the transmitter room. The 6” copper transmission line carrying the channel 50 signal to the antenna is seen going up near the center of the tower.

Framing the living quarters for the individual providing  security at the transmitter site .

I will digress for a moment and share an experience that occurred while stacking. First, I should mention that guy wires are not small. They can range from 3/4” to 1” or more depending on the load they will carry. They are shipped on huge wooden spools and weigh thousands of pounds. Each cable (we had a total of 18) are custom cut to the specific length needed. There is little room for measurement error. Being custom made it can take months to get a cable made and delivered.

I was working at the studio one day when I received a phone call from a tower worker telling me a set of cables were too short! I immediately got in my car and made a mad dash to the tower site. When I arrived the crew had stacked about half the tower. All guy wires were attached to anchor points A-1, B-1 and C-1 (see image above showing anchor points). The crew had stacked to the point where the fourth level of guy wires needed to be attached. The wires extending to anchors A-2 and A-3 where fine. However, the wire going to anchor B-2 was short. It was at the end of the attachment U-Bolt and the tower was slightly leaning towards the B-2 anchor because of the guy wire being short! Tower work had to stop until this issue could be resolved. It was Friday afternoon, so with heading into the weekend I was concerned there would be little we could do until Monday. I got on the phone and called the surveyor who did the ground work layout (i.e. the tower anchors and foundation). I told him about the problem. He was unavailable to come out that afternoon and do any measuring. Not accepting “No” for an answer I grabbed the yellow pages (how many of you reading this remember what those are) and “Let my fingers do the walking” under the heading of surveyors. I found a surveyor that could mobilize a crew on Saturday. I went for it. They arrived on Saturday morning and measured the angles and elevations of all anchor points. Their results were within an inch or so of the original surveyor except for the elevation of anchor B-2. They found that elevation to be about 3 feet lower than the original survey! When I called the original surveyor on Monday and told him what we found he pulled out his notes. Upon hearing the word “oops” on the other end of the phone my heart sank. He said he had made a miscalculation and asked if that was a major problem. Of course, I said it was.

I then called the tower fabricator, Stainless, Inc., and spoke to their Chief Engineer. He said what we were experiencing had happened before and suggested extension plates be fabricated to attach to the end of the guy cables to make up for the length shortage. My concern was how long it would take to get the extensions fabricated. It would cost a lot of precious time and money if the tower crew had to pull off the job for a week or so. The engineer sent me a drawing of the extension plates he proposed with the dimensions. I was hoping I could find a local fabricator.

Dr. Al was blessed to have another talented person on his Board of Directors. Tom Gaskell had a company that manufactured bolts and rivets. He had the equipment to fabricate the plates and get them galvanized for rust protection. Tom cranked them out within a few days. The plates worked great and we were now back on schedule for tower stacking with only a couple of days delay. When the stacking was completed the antenna was lifted up and mounted on top. Even under ideal conditions stacking is a slow process and can take weeks to stack a tower.

The kick-off event to begin stacking the sections of tower is the setting of the steel plate that the first section of tower will rest on. We had been sent a drawing showing the location where the bolts in the foundation needed to be set to line up with the steel plate. When we received the plate we noticed that the holes in the plate didn’t match up with the pattern that Stainless sent. Argh! I could see days of delay while waiting for another plate to be shipped. Thankfully, Dr. Al had a talented person on his Board of Directors, Gene Land, that owned a machine shop. After consulting with the Stainless Chief Engineer, I took the plate over to Gene’s shop which was not very far away. He was able to bore new holes in about an hour. We were now back in business and could proceed in getting the plate mounted and the first tower section erected so we could begin stacking the others.

The photo above on the left is the front of the Harris BT-55UI UHF television transmitter. To the right is what the rear of the transmitter looks like. As you can see this is not a small piece of equipment. The drawing to the far right is of a Klystron tube. This device takes a signal of a few Watts in and amplifies it to 55,000 Watts! This transmitter used two of those tubes. One for audio and the other for the video. Most stations keep a spare on-hand in case the one in service fails. This tube is about 5 feet tall and has to be loaded in the transmitter from a carriage assembly on wheels. The picture of the tube has been sized to show how it would align in one of the cabinets show on the back of the transmitter.

One other interesting item, notice on the rear view the round domes on the stop. This tube was cooled by water. It would boil the water into steam. The steam would be collected in the dome and condensed back into water with a huge coil and fan unit, called a heat exchanger, and sent back to the transmitter for another cooling cycle.

Klystron tubes were not cheap and could cost as much as $50,000! They might last for 3 to 5 years.

Front of the KYFC-TV Transmitter

Rear of the Transmitter

Klystron Tube