FM Nights

WUVT held a Stereothon (I think I might still have a poster that we sold to raise $$) and bought an Orban Optimod 8000, the first high performance integrated stereo generator/processor from this now premier audio processing company. I think the AM revenues also helped out. Dave got the thing installed at Lee Hall, and Jon got a pair of phone lines in. Graduation became Dave’s priority, so Jon asked me to help in FM engineering. Together, three or four of us pulled off the first stereophonic proof of performance for the FCC, something none of us had done before. I remember that things like crosstalk, separation, and pilot phasing were all so foreign and difficult the first time, and the phone company screwed us with noisy line equalizers to get the 15 KHz flat circuits. The 1976 engineering department included Jon Banks, Jeff Bevis, Joel Damiano, Bill Suffa, Tom Finn, Mark Stein, Howard Fleming, Walt Bailey, Steve Lokitis and myself. Mike Williams, Randy Hudson, and Bill Brideson were sort of freelance consultants hanging around WUVT.

The FM transmitter final amplifier was called a GNM69, the type acceptance number of this used homemade transmitter that we got from Georgia Tech. Funny thing about that number, I went to work with an engineer in Quincy, Illinois at Broadcast Electronics in 1980. His name was Geoffrey N. Mendenhall, and he built the Georgia Tech rig. Later I worked for him. He is now an executive at Harris Corporation in advanced developments. Geoff won the 1999 NAB engineering award for excellence in broadcast engineering. Anyway, the GNM69 delivered about 430 Watts from the single 4CX300A tetrode. Into our antenna, "770 Watts ERP from high atop Lee Hall on Washington Street on the Va. Tech campus." The antenna [below, left] was a BFI-2H horizontal polarized thing, with sash cord for guy wires. We used to have to go and smack the mast with a board during icing, to keep the transmitter from blowing a fuse due to high reflected power. It was no fun in the middle of the night, but anything was done to keep the Woove on the air then. We built a quick controller with remote control hooks for the studio to turn on and off the transmitter, raise the power, go stereo or mono, and handle the transmitter timing. The stereo overhaul was also happening with all studio wiring replaced for stereo. Jon did a wonderful job of this, all balanced circuitry with shielded cables. WUVT-FM was one of the first radio stations in this part of the state to have an Optimod on the air. It sounded really nice when the processing was backed off. A lot of folks worked to design, modify, or operate the 90.7 FM system, including Jon Banks, Dave Landers, Randy Hudson, Bill Brideson, and myself. We made the switch panel removable so that one could fire up the transmitter while standing a few feet away, just in case the GNM69 decided to belch out flames and sparks. It did this infrequently, but when it did, it was nice to not have to change your shorts. There's a photo of me [above, right] standing there in front of the rig in that tiny closet on top of Lee Hall. Later, we got a bigger space, when we went to higher power around 1979.

I remember Ernie K would tease the FM staff as the "FM bed-wetters", not in real radio like AM. I got indoctrinated into jazz on FM by Harrigan (was it Jim?) who left for the Peace Corps. I did a gig for 3 years, every Saturday from some ungodly hour til noon, sometimes following the Gospel George show. I plowed into the wonderful jazz LP collection at WUVT – it went back to the 1940’s, thoroughly covering the bop era. On some weekends I would sit through the afternoon at the Met (opera) and also run "Earplay", an LP of radio drama. It was a great time to clean the cart machines, fix things in engineering, and take a long shit. I did learn a lot about opera at the time, listening to the intermission programming. The studio repairs always ate my Saturdays. I was also the Jazz music director which was under the music director. I wrote our reviews for Sabins Jazz newspaper, and worked with the record companies to improve offerings to the station.

Jon Banks had dropped out of Tech and did local radio work in Pulaski, and the rules required a student to be engineer. So I took the task, and Jon became a contractor on the AM revamp project of the summer of ‘77. Jon and Tom Finn lived in a trailer home, and one night it burned down. I remember us searching the charred ruins looking for the WUVT keychain, that Dean Brown had issued to Jon. It had all of the steam tunnel door keys as well as the Lee Hall closet key and elevator room key. It was an important keychain for us! At the time, I think WUVT had more licensed Second and First Class Radiotelephone operators than most stations in the state, having a good supply of EE’s from Whittemore Hall. In addition to the list above, came Bob Crockett. He was a very capable and energetic engineer, now in charge of amplifier production at Harris Broadcast.

In 1978, before I graduated, we applied to the FCC to raise power to about 3 kW horizontal and vertical. We got good advice on how to do the paperwork from David Landis, FCC chief of the Broadcast Bureau, through contact with Carlos Roberts who had worked at WUVT earlier. He forwarded my request for help to the proper FCC channels. Jon and I did the paperwork, with help from incoming engineer Bill Suffa, Bob Crockett, and others. We found an ancient 3 KW RCA transmitter in Baltimore, with help from Floyd Daisy and Dwight Weller (who passed away 10/97). Here's Mark Stein [above, left] checking out this hulk. We hauled it down to Tech on a small trailer. I graduated before it made it down. It barely fit the elevator, and was installed atop Lee Hall, next to the elevator motor area. This was the beginning of WUVT's high-power FM operation. Steve Floyd also played a role in getting the higher power transmitter online. Here he is [at right] with the new antenna needed for higher power Steve continues doing RF engineering at an electronics company in Northern Virginia. His lastest work is engineering for the Haarp program in Alaska, beaming RF into the ionisphere. Bill Suffa is now one of the Washington broadcast consulting engineers. The RCA 3 kW transmitter looked pretty spiffy once the guys polished and rebuilt it.

In the first half of the 1980’s I designed FM transmitters for Broadcast Electronics, Inc. in Illinois. Dave Cowan, then CE of WUVT, worked with me to convince the company and VPI to swing a good deal for the college. I think the main thing was that I gave a free personal install visit to Blacksburg. I was proud to have my own baby, the FM-3.5A, on WUVT. We installed it overnight, and it worked I believe that it is still at WUVT. It uses a 4CX3500A tetrode, the first transmitter series on the market with that now common tube. The Optimod was still there the last time I was in Blacksburg (in 1992).

AM Days

I part-timed for Lew Bagwell doing engineering at WJJJ/WVVV – kept the Collins FM on the air during the ball games. My roomate at the time, Randy Hudson, helped me cover these part-time opportunities. Matt Eakle and others from WUVT worked at WVVV at the time. I also worked for Don Fleeger at WKEX, where a window fan blew air into the rear of a Sintronics/Singer 1KW transmitter that could barely make power. I remember finding half their guy wires were wrapped around cow turds for support. I tightened the turnbuckles, and the entire tower groaned and twisted into a crooked shape. Oops. I went back and loosened everything so it was straight again. At WUVT we faced many technical challenges, and solved them through a steady dribble of funds requested from dean of student services J. Gordon Brown. He convinced me to get a haircut when I graduated from Tech and was interviewing for work.

We had a 50 Watt commercial transmitter on 640 KHz in a stuffy janitor closet of the first floor of Lee Hall. I liked the beast, except for the inadequate power transformer that seemed to melt down every September, when Tech would reset the clocks by sending a thousand cycle tone over the powerlines. Interesting coincidence. The thing also ate tubes, so it became one of the major annual AM operating expenses, as did the FM transmitter final tube. The manufacturer would hit WUVT for about $150 a year, to replace the melted-down iron. Finally, we found some big boat anchor plate transformer in the basement of HC Baker Sales in Roanoke. I mounted it on a small outrigger chassis, and it spelled relief for the transmitter for years to come. The 50 Watt LPB had a pair of 6550 beam power tubes for RF, plate modulated with a pair of the same. We ran it hard, so that each fall we replaced the tubes. It would modulate well over positive 100% and sounded good for carrier current. A schematic of the LPB transmitter is attached as lpb50.pdf. Generally it was a nice transmitter. I wonder if it still works at WUVT?

The repair of the Radford College transmitter system, which we colloquially called WDUD. Randy Hudson built this nice 50 Watt transmitter that used 807s for the RF stage, modulated with a pair of 7591 hi-fi tubes. It had a VFO, so you could vary the frequency around 640 KHz, to try and set a zero beat note with the Akron, Ohio station at night. Hud’s transmitter fell into disrepair when no one paid attention and the Radford RF couplers were in a terrible state, with some coaxes in flooded steam tunnels. The Radford tunnels were horrible compared to VPI's. The WUVT mole squad of engineers loved to work at Radford, as it was mostly females, and they often used the rooftop of their high rise dorm for tanning. Luckily, one of our coupling boxes was in a closet upstairs. We did a renovation there, and I almost lost a finger on one of the steel gratings leading under a sidewalk into the tunnels. AM-64 was back on in Radford.

Jon Banks redesigned the entire AM distribution out on the lower quad. Jeff Bevis, Jon, Tom Finn and I spent a lot of time crawling through the steam tunnels in the summer of ’77, laying miles of new coax and installing new powerline coupling boxes with mica matching capacitors tuned for each building. Someone’s earlier method of building transistor linear amplifiers throughout the campus had failed due to the heat in the tunnels and the poor reliability of power transistors in the circuit. We went back to the old method of driving a long network, with several higher power transmitters. We worked hard to contain leakage from faulty connectors and coax, especially where it would cause our signal between transmitters to cause a beat note in weak areas. Every fall we would go out and tweak the oscillators to get them synchronized, before applying audio.

The upper quad was powered with a Vara-power transmitter at about 15 watts from an 807. It was in the steam plant machine shop. I remember marching in with our hard hats, while these burly machinists would watch us. We would go read our meters, and bang on the transmitter, up on a little shelf in the back. These transmitters were totally open, and one could get nailed by the high voltage if not careful. They were designed by H. L. Hopewell and Sam Straus, the chief engineer of 1959. They were modular with plug-in units for the oscillator and the final amplifier. These things would sit in the steam tunnels and play until the tubes finally got so weak. But they were old, and sort of dangerous. They also didn’t modulate well at the highest processed levels that WUVT was trying to reach at the time. We had learned that in overcoming powerline hum, it was important to have high density (>100% on positive peaks) modulation -- same thing real radio stations had to deal with. WUVT-AM was highly processed at the time, with both CBS Volumax and Audimax processors cranked up. The attached schematics, vara_power_xmtr.pdf, show the entire rig. Finally, we replaced them with one new 25 watt LPB transmitter that used a single Compactron tube for the RF. It worked well, and was lightweight. I think we may have bought a second one for a backup and troubleshooting transmitter.

The Gospel of Carrier Current at the time was Ludwell Sibley’s manual on Carrier-Current System Design. It was a collaborative effort by Sibley and engineers from KZSU (Stanford U), KALX (UC Berkeley), and KCSB (UC Santa Barbara). LPB, the transmitter company, also offered a series of free tech notes on limited area broadcasting. WUVT was responsible for an elaborate and complex carrier current network. Looking back, I am amazed that we kept it working. Nowadays, I suppose AM radios are scarce in dorm rooms.

After I Graduated

I helped when WUVT moved out of Squires during the renovation. We picked an STL system at 930 MHz to send the audio over to Lee Hall, finally eliminating dependence on Telco circuits once and for all. Later we installed an SCA subcarrier on FM to deliver the AM programming to the remote transmitters. This happened after I left BE, in the late 1980s. It used a BE SCA generator prototype that was donated. WUVT bought SCA receivers for each transmitter site. It sort of worked, as we fed the SCA subcarrier over the FM STL from the studio, and had to move the subcarrier frequency high enough (76 KHz) to prevent interference with the stereo signal for FM. I think we did observe some effects from being on the second harmonic of the stereo subcarrier, however. WUVT moved into the upstairs of a bank building down on Main Street. Here are some photos I took during that work; we brought a lot of ex-engineers back to use their professional skills to put the temporary studios in, all in one week.Leslie Plummer was pulling the alumni network together then, and we all had a great time in town, and at the Econo Lodge afterwards. I’m saddened that I have not been able to pay visits to WUVT anymore. I left Delaware and the East Coast in 1992, after working for E. I. Dupont de Nemours and Company for six years there. I am now RF engineer for a large particle accelerator at Los Alamos National Laboratory in New Mexico. I still work with high power RF, at megawatt levels - still using vacuum tubes, too. WUVT prepared me for an enjoyable career in doing what I like to do. But I did not stay in broadcasting. I got out before the 'digitization' of everything in radio. Randy Hudson (Hud), Jon Banks and I all live near the Rockies now, and we chat often.