TECHNICAL HISTORICAL, AIR, LAND, AND SEA EXPEDITION INFORMATION

My experience indicates very few people collect or are familiar with radio insulators. Like Lightning Balls and Vanes, more people are inquiring, collecting; therefore I share the following information:

Many thanks to Mr. Walter E. Lehnert of 5209 Minnehaha Boulevard, Minneapolis, Minnesota 55424 for providing me with the information from original QST Amateur's or Ham's magazine issue November 1928 p7l, December 1929 p96, September 1930 p67, February 1930 p69, and May 1931 p96. This information is needed by all who want or have a collection lying around of these large and small radio insulators as shown per sketch 1. They were first illustrated on page 9, 10, and 11 of Insulator Magazine November 1972 issue.

Corning Glass Works Dept. 64 Industrial and Laboratory Divisions, Corning, New York published a booklet in 1928 titled PYREX RADIO INSULATORS. As quoted, "Over 300 broadcasting stations, leading radio telegraph systems, the United States Army, Navy, Air Mail, Coast Guard, and Ice Patrol Services, Explorers like Commander Byrd, and Amateurs everywhere have utilized PYREX insulators in many spectacular achievements." "Regardless of whether you are sending or receiving--on Land, Sea, or Airplane, you should be thoroughly familiar with the Pyrex Antenna, Strain, Entering, Standoff and Busbar insulators that are helping make these leaders radio history."

Technical information researched and quoted from the Pyrex ads, QST magazine 1928 and 1929 as follows: "Semi-tropical rains and moist salty atmosphere do not impair the protection because PYREX insulators have a dense impervious surface that sheds water and collects no deposits." "Likewise in dust and smoke-laden atmosphere, particles that settle on PYREX insulators are blown off by wind and washed off by rain, in any location there is no deterioration in insulating value."

"The mechanical strength of PYREX insulators is equally permanent, so that once they are placed they assure continuous operation." "In a number of instances, storms that wreck wiring and towers did not break the Pyrex insulators." "Their exceptionally low coefficient of expansion makes them indifferent to sudden temperature changes." "Their dielectric strength is from 15% to 35% greater than Porcelain." "Their power lost is lower than any substance except pure fuzed quartz."

The Pyrex insulators illustrated per sketch 1 and page 10 of Insulator magazine November issue 1972 were used in the radio room of the ship and antenna system of "CITY OF NEW YORK" during the FIRST 1928 ANTARCTIC EXPEDITION led by Commander Byrd. They were also used on his first PRE-TRANS-ATLANTIC FLIGHT by air over the same pole. Mr. M. P. Hanson, Byrd's Chief Engineer, writes as quoted, "We have every confidence that your product will render good service under extreme conditions to be met, as they have done in the past." THE REST IS HISTORY*****

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TYPES OF PYREX RADIO INSULATORS SOLD IN LATE 20's, Reprinted from Radio Magazine, Original Prices

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The long white porcelain antenna insulators Numbers 38-200 to 202 above are used on the antenna tension lines in radio stations, on land or sea stations. Each end has brass fixtures (NOT SHOWN) which enables insulator to be connected in series or attached side by side with hooks. Any quantity of them can be used.

Sketch 2. Small Pyrex Radio Antenna Insulators

In 1929 Broadcasting Station WQAM, Miami, Florida used the Antenna Installation system as illustrated in sketch 1 with the Pyrex Radio Entering Bowls and Strain Type. The PYREX Navy Type Entering Bowl coupled direct to the end of the antenna carries the lead-in squarely through the center of an opening in the wall, and two PYREX Strain Insulators in series on each anchorage and tension line keep the radio energy IN and the disturbing stray secondary currents OUT of the antenna. The large view-type is used in radio stations also by hams as illustrated in sketch 1. These bowls can be used as individual insulators and placed not only on the wall, but the ceiling. Small Pyrex radio antenna insulators were also used in these systems and are shown in sketch 2, along with their original prices and numbers as taken from the 1920 radio magazines. I'm quite sure most collectors have this type in their collection. These insulators or ones similar are still made for present day radio antenna systems, but mostly made of porcelain instead of glass.