Earliest Notable Use of Part 15 AM Broadcasting

.. or perhaps it should be called the earliest specialized use of pat 15 AM (using 15.209 or 15.219) that I know of.. It took place in Vicksburg NMP...

Vicksburg National Military Park was established February 21, 1899 to preserve the site of the American Civil War Battle of Vicksburg, waged from March 29 to July 4, 1863. The park,

located in Vicksburg, Mississippi, includes 1,325 historic monuments, 20 miles of historic trenches, a 16-mile tour road, a 12.5-mile walking trail, a 116.28-acre National Cemetery, 144 cannons, the restored gunboat USS Cairo (also known as the "Hardluck Ironclad") which  on December 12, 1862 became the first U.S. ship in history to be sunk by a torpedo, and also  contains the canal ordered by Ulysses S. Grant to be built by the Union Army for their ships to bypass Confederate artillery fire.
https://www.nps.gov/vick/index.htm

Bet you didn't know part 15 AM broadcasting existed in the 1800s, huh? Well it just so happens the following quote by President Abraham Lincoln was very likely to have been heard on radio via a part 15 AM broadcast:

 "See what a lot of land these fellows hold, of which Vicksburg is the key! The war can never be brought to a close until that key is in our pocket... We can take all the northern ports of the Confederacy, and they can defy us from Vicksburg." 

 

Don't believe it? Its actually probably true --But of course that part 15 broadcast of Lincolns remarks occurred about a century later in the mid 1950s!..



McConaghie
circa 1940s

James McConaghie, (aka "Mac") was Superintendent of Vicksburg National Park from 1941 thru 1959. In the late 1940s he demonstrated a portable electric map that his staff took to schools. A decade later similar maps that would light by a visitors push a of a button became commonplace at historical parks around the US. He also noted the Washington Monument had a recorded message playing so he proposed to install coin-operated record players at Vicksburg tour stops, but his idea was shot down. Nevertheless, by the mid-1950s visitor-activated audiovisual devices came into wide use, and by 1963, 90 parks shared more than 100 audio stations and dozens of automatic movie and slide programs, and modern projection/sound equipment was installed in 46 amphitheaters and campfire circles. ~ INTERPRETATION IN THE NATIONAL PARK SERVICE: A HISTORICAL PERSPECTIVE

So needless to say, Mac had a tendency to know a good idea when he saw one, which brings us to the specialized broadcasting with part 15 AM in the 1950s. Something gave him the idea to use a 100mw hobby AM transmitter to lead caravan tours in the park. Such tours already existed but it involved tourist following and making frequent stops to exit their cars and hear the interpretation of every locale.. Mac saw that using radio would be a better option.. but there was a problem..

During the 1950s radio receivers in cars was still a bit of a luxury, they weren't a standard inclusion like they are today, it was often an extra which many opted out of paying, also the school field trips which arrived on buses, none of them had radios either.. But Mac took it upon himself to remedy that problem by buying inexpensive radios from junkyards, presumably then wired to be powered from the cigarette lighter, along with suction cup held roof antennas to provide as loners to those visiting the park which didn't have a radio already installed. So with that taken care of; all he had to do was transmit the messages to the moving vehicles

"Mac" explains how it was accomplished with only a $30 budget: A little over a third of the expense went towards

the purchase of a "Knight Wireless Broadcaster" kit which the 1956 Allied Corporation Catalog shows on page 64:
The Knight transmitter kit was $8.75 (tubes included).
It's instruction manual and diagrams was 10cents.
The crystal mic with a 5ft cable was an additional  $3.95,
On page 204:
A 96" stainless steel whip for $5.14 or a cadmium-plated one for $3.67.
Economy base body antenna mount for $5.07 or bumper mount for $4.09,

That's about $23 so far but I presume some kind of ATU would be required to use a whip with the Knight kit, but that alone showed to be $24 which blows the $30 budget, so maybe he constructed one from scratch for $7.00.
If you wanted to include a copy of the FCC part 15 rules from the Government Printing Office that would have been another $

The following article reporting this part 15 AM broadcast was written in 1957, but those broadcast had already been going on for some unspecified amount of time prior to publication and his interpretive radio caravan tours probably continued for years after.

There have been several similar audio tours since with part 15, but documented reports (other than this one from the mid 50s shown below) didn't begin showing up until the 70s and thereafter.



In the present day Vicksburg's NMP still provide similar audio tours, however they apparently have abandoned the part 15 AM way of doing it,  opting instead for other methods such as the “GPS Ranger” using your smart phone or purchasing their CD which you play in your car for the tours... Takes away the charm of it all I think, using traditional radio would be better. However other parks still utilize part 15 for their audio tours; one example is the Savannah Wildlife Reserve driving tour featured in a previous post:   
We part 15 broadcasters could produce similar type caravans today should some kind of group  mobile event occurs. Or maybe you can create a special mobile event of your own!