Carol of the Bell

Through the 70s and 80s AM and FM stations were constantly looking for new ways to maximize their signal on the dial - making your station stand out above the rest of the stations on the dial. The most common competition among stations and their processing was to be the loudest on the dial.

For some stations, there was also something behind the scenes that slightly affected the loudness of the main FM signal. That's the use of FM subcarriers for subscription services.

How the FM bandwidth of one radio station can be used.

At KWWR, we not only tried to maximize the sound of Country 96, but we were also using the FM subcarriers for subscription services. That made being loud a challenge, since each subcarrier used a portion of the total modulation allowed by the FCC.

Background music, piped in music, elevator music or Muzak were common names for one use of the first FM subcarrier at 67 khz. Using special receivers, that service could be sold to retailers, businesses, industry and restaurants for background music.

Not every market had someone utilizing the FM subcarriers but quite a few did.  In Mexico we used 67 khz for background music and 92 khz for contemporary music. When the 1000' tower was constructed, a 3rd subcarrrier was used to transmit control data from the studios to the transmitter building using 110 khz. While the first two produced revenue, the third was just for our private use.

In our part of Missouri, FM subcarriers were being used for subscription services on KJFF in Jefferson City (which later became KTXY), KWWR in Mexico, KRXL in Kirksville and WIL in St. Louis. Public Radio stations, like KBIA, at colleges and universities frequently used 67 khz to transmit reading services for the blind.

In Jefferson City, the subcarrier of KJFF was tested for use as a way to distribute The Missouri Network (instead of phone lines). But that didn't prove viable and The Missouri Network eventually went to satellite delivery. We had a test receiver for a while in the basement. It was very interesting to hear Bob Priddy and his unique voice in full clarity on the FM subcarrier, while the feed on the phone lines sounded tinny by comparison.

In Mexico, the original 67 khz subcarrier was fed by a cabinet filled with cartridge tape machines and timers that sat in the central office area on the main floor. The timers would rotate the tapes so the same songs wouldn't play at the same time or in the same order all the time.

On one excursion into First National Bank in Mexico, several of the tellers asked me if I could get the background music guy to change a particular tape. There was a song that played every day around 2 PM that the tellers eventually found annoying, and in the bank that day, they pointed to the speakers in the ceiling and said, "That song!". So when I got back to the station I said something to the guy who handled the background music and he said he had forgotten to rotate the tapes in recent weeks. He made some changes, so hopefully that one song quit playing at 2 PM every day.

That particular guy was eventually replaced by the owner's son and the owner's son grew the company from those two music subscription services and expanded into drive-thru systems for fast food restaurants and security video for businesses. Quite a few years back, the background music company separated from the radio station - and with small satellite dishes becoming common - the FM subcarriers were no longer used for subscription services.

To show how the background music company grew - subcarriers were also leased by us in Kirksville, Eldon, Boonville and Carrollton  for subscription music services beginning in the 80s. As the engineer for the station, I was involved in setting up not only the first 11 foot dish for receiving the background music feeds in Mexico, but also installed a satellite dish at KRXL and involved in upgrading some equipment in Eldon for the subscription channels there. At Boonville, KWWR was used as the distribution path to get the subscription music services to the station for their subcarriers.

For stations that used subcarriers for subscription services - you had to be careful when you took the FM station down for maintenance - since that also affected all of the background music service customers. In Mexico the background music company would get some service calls for the subscription service going to static late at night a few times in the 80s as we experimented with different processing to maximize Country 96.

And now I come to the title of this post - Carol of the Bell.

In the 80s, we did an on air auction every February called Bids for Bargains. It ran from 5-6 PM weekdays all during February.  Businesses would give the station merchandise and in return get an advertising schedule for the value of the merchandise. The station would then auction off the merchandise on the air to the highest bidder and it helped make February a profitable month - where in the past the FM advertising part of the business got extremely slow that time of year.

The entire staff participated in Bids for Bargains - some of the on air staff, the sales staff and office staff all joined forces for the daily broadcast and to man the phones for bidders calling in. We tried to make Bids for Bargains entertaining, while trying to make money for the station, so at times it sounded like a morning radio show. There were also a couple of things used as a special audio signal for listeners. A bicycle type horn was honked every time an item sold. And we had "instant bargains" - like restaurant dining out certificates - that we signaled for listeneers by ringing a small silver bell.

It wasn't long before the background music company was getting phone calls about a bell sound on the background music every day between 5 and 6 PM, as the main channel was bleeding over into the 67 khz subcarrier every time we rang the bell.

We worked with McMartin Industries, who manufactured the receivers for the background music feed to find  out how to keep the bell out of the background music channel.

Not only was I involved in my regular daily duties at the station, I also became a key part of the daily Bids for Bargains broadcast - AND had to work with the background music company to keep the bell from interfering with their customers.

So working at KWWR during the 80s was far from just being a disc jockey. We had our hands full for a while.

Man, that WAS radio!

So it goes.