INTERNATIONAL MARCONI DAY SPECIAL EVENT
Saturday April 21, 2018
The International Marconi Day is held yearly on the Saturday closest to Guglielmo Marconi’s birthday. This special day celebrates Marconi’s important ground breaking contributions to wireless transmission. Over 60 amateur radio stations around the world that have some special Marconi connection will be on the air. Our special event station has been selected to be one of these official International Marconi Day stations and will be operating from San Diego, CA. We will be setting up our station on Fiesta Island, in the middle of the San Diego Mission Bay, in order to contact as many of these “official” stations as possible using the special event call N6M. We will also be making contacts with the general amateur radio population and will be operating both CW and SSB. To commemorate Marconi’s 1901 transatlantic transmission, which used a kite to support his aerial, we will also be flying a Marconi replica kite that will be supporting our antenna in an attempt to duplicate his historic results. The details of this special event station are as follows:
The International Marconi Day event will be held Saturday, April 21, 2018.
We will be setting up our special event station on the North West tip of Fiesta Island. This sea level location is within line-of-sight of both the original Point Loma and Chollas Heights wireless broadcast station sites. This operating location has the advantage of an unobstructed view toward the U.S. East coast and Europe over the salt water bay.
We will be operating on 20 meter SSB (near 14.245 MHz) and CW (near 14.027 MHz) using the Special Event call sign N6M.
Our Special Event Station has been selected by the event organizers as an “Official” International Marconi Day station. Amateur radio stations from around the world can contact us to earn points toward Marconi Day awards.
Our station will also be making contacts with as many of the other International Marconi Day stations as we can.
The International Marconi Day organizing group is the Cornish ARC. Their site provides additional information about this event at www.GX4CRC.com
This Special Event will be hosted by Bob (W6SDO), Mert (AF6HF), Dave (WB6SQA), Bob (KJ6EJW), Bill (K1CT) and Baron (K6VWL).
For additional information contact Bob at W6SDO@aol.com
This summary of the first “wireless” operations in San Diego and their connection to Marconi is based on information provided by Navy records, numerous published reports and documents in addition to newspaper accounts from the period.
At the turn of the century, wireless telegraphy hit the world with a dramatic impact. Immediately the U.S. Navy invited Gugleilmo Marconi to conduct experiments in America to see if this new technology could be successfully applied to Navy ship-to-shore communications. As a result of this program, a 5 kilowatt spark-gap transmitter was installed in a small wood framed building along a rutted dirt road on a hilltop near the tip of Point Loma peninsula. The transmitter was delivered to the facility by a horse drawn wagon.
This location overlooked the San Diego Bay and Pacific Ocean and provided an excellent location for testing, evaluating and improving the reliability of the new ship-to-shore technology. The nearness of this San Diego location to the Pacific Fleet also meant that this facility could readily support the fleet needs. This station was given the call letters NPL. Immediately the distance record for Navy wireless communication was extended from 125 miles to over 500 miles. Even with limited equipment and facilities, in excess of 3,000 messages were handled during the first year of operation. This facility continued operating until June 1949 when it was decommissioned.
The Navy soon realized that a much larger and more powerful facility was needed in order to advance the ship to shore communications research. Therefore a new component was planned for the U.S. Naval Communications Station San Diego that would be located on a 73 acre site 476 feet above sea level and overlooking the San Diego Bay and Pacific Ocean. This new station would be called the Chollas Heights Naval Radio Transmitting Facility and was commissioned in 1917 and was operational in 1919. At this time the call sign NPL and transmitting duties were reassigned from the original smaller Point Loma facility to this new Chollas Heights facility.
The Chollas Heights station had three 600 foot high Marconi towers that were arranged with a triangular footprint. The collective weight of these towers was over one million pounds. A phosphorous bronze aerial, weighing over 1,000 pounds, was supported from the top of these towers. Since the base of the towers at 476 feet above sea level, the aerial was at more than 1,000 feet above the San Diego Bay and Pacific Ocean below.
The aerial was fed by a 200 kilowatt arc transmitter operating on 30.6 kilocycles. At the time of commissioning, this San Diego facility was the most powerful in North America with an unprecedented range of 12,000 miles.
With this improved range and reliability of communication, Chollas Heights station was used to conduct worldwide testing with ships at sea, many of which were using Marconi transmitters. The Chollas Heights facility also played a vital role in communications during the latter half of World War 1 as well as during World War 2 when the Chollas Heights facility provided the only direct and reliable communication between Pearl Harbor Hawaii and the Navy’s headquarters in Arlington Virginia. It was this radio link that broadcasted the first report of the Japanese attack on Pearl Harbor on December 7, 1941 which read:
“Japanese attacking Pearl Harbor. This is not, repeat not, a drill”
The Chollas Heights facility was decommission September 1992 and the towers were demolished by controlled explosive demolition in in November 1995. A museum now exists on the site and contains many artifacts from this historic and world class station
Last updated April 28, 2018
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