THEY COME IN DIFFERENT SHAPES AND COLORS f
fààÜÜtt||ÇÇáá Another Insulator According to WEBSTER'S DICTIONARY . . . a Strain is a nonconducting substance or body, as porcelain or glass, used in insulating wires, etc. Cf. (compare) Conductor, nonconductor. Radio Antenna and Electrical ... STRAINS STRAIN INSULATORS were first used in tele- graph sys tems to isolate the signal wire from the ground while still supporting the radio antennas. A "typical" strain insulator is a piece of glass or porcelain that is shaped to accommodate two cables. The shape of the insulator maximizes the distance between the cables while also maximiz- ing the loading transfer capacity of the insula- tors. The total measurement of the ribs and the space between the ribs determines the electrical length of the insulator from eye to eye. A short, compact in sulator with more ribs and deeper val- leys has more electrical length than a longer one with less or no ribs. Some strains are smooth ­ some have ribs. They were used to break the electrical path in any wire link, such as in guy wires used to sup- port utility poles, dead-ending the ends of elec- trical power lines, and overhead power lines. Note that the interlocking connection wires on all strain insulators (except radio an tenna strains) prevent the wire from falling should the insulator become broken. Several older styles of high volt- age strain insulators intended to dead-end feed- er wires were mounted vertically between two cross-arms by means of a wooden or metal rod or pipe. The large styles were composed of a smaller porcelain part cemented inside the larger diameter por - celain sleeve. Radio antenna strains were used in homes, on military antennas, aircrafts, commercial re peaters, TV and Radio Broad cast antennas, and boats. Electrical strains were used on power lines. They were made by various glass, bot- tle, and insulator manufacturers; porcelain man- ufacturers; and marble manufacturing compa- nies.There are hundreds of different names of strains from various places. A few names are Pyrex (NY), Fleron (NJ), Brilliant (OH), Sensory (PA), A.G.K. (NY), Locke (MD), Ohio Brass (OH), Knox (TN), Zicme (Columbia), L.S. Brach (NJ), Birnbach (NY), and Lapp (NY). Strains were made of porcelain, glass, Steatite, plastic, metal, resin, fiberglass, com - posite, wood, etc. Where can you find old strains today? . . . You can find them on/in barns, houses, old poles, sales, flea markets, antique shops, and on the in ternet. Anatomy of a Strain drawing from A Collectors Guide for Radio Antenna Insulators (CD) Glass Radio Antenna Strains in Various Colors ... Sharp Ribs - and - Round Ribs m
e
a
s
u
r
e
d

e
y
e

t
o

e
y
e 2'' 1½'' 1-5/8'' 1½'' 1-5/8'' 1¾'' 1-5/8'' 1¼'' This strain is embossed FLERON and was made by Star. The color Nu-Blac is a trademark dark gray color. Radio Antenna and Electrical ... STRAINS 1¾'' Artwork Courtesy of Old Familiar Strains. . . A great publication devoted to research on strains. STRAIN STRAIN Example of how a radio antenna strain worked LEAD-IN STRIP PORCELAIN NAIL KNOB SCREW EYE BRASS CONNECTOR ANTENNA LEAD-IN GROUND ROD GROUND CLAMP SPRING CONNECTOR LIGHTNING ARRESTER PORCELAIN STRAIN INSULATOR Notice the different shapes and number of ribs and no ribs of these strains E
Egggg aanndd JJoohhnnnnyy BBaallll SSttrraaiinnss compression style Folembray Egg (Aisne, France) Airplane Style ?Cook Pottery (Trenton, NJ) Probably made by Hemingray or Brookfield (NJ) Porcelain Strains tension style W
Wooooddeenn aanndd GGllaassss SSttrraaiinnss tension style ZICME Spiral Groove marked with backward (Columbia) JOHNNY BALLS (Guy Wire Strains) X äxÇ áàÜt|Çá zÉà ytÇvç4 This jeweled-looking strain was made by D.C. Jenkins Glass Co. (Kokomo, Indiana) L. S. BRACH (Newark, New Jersey) Wooden Trolley Strain 9½'' G 3'' 3'' 4'' 2½'' 2¼'' 2½'' 2½'' 1¾'' 1½'' 2½'' 2¼'' EGGS 2½'' 2'' 1½'' 1¾'' 2¼'' 2'' 2'' 2¼'' 1½'' NICKNAMED "Hand Grenade" Duquesne Light Co. / Embossed: D L Co P
Poonnttiill GGllaassss aanndd EErrrroorrss A Collectors Guide for Radio Antenna Insulators (CD) ­ Bob Alexander and Jim Dombrowski Old Familiar Strains ­ Dan Howard and Keith Roloson National Insulator Assoc. (NIA) · ICON ­ Bill Meier Lois and Steve Blair · Elton Gish · Caleb Thimell · Rick Soller David Sztramski · Bernie Warren "THANK YOU TO ALL" ... and a Special Thank You to Jim Dombrowski for his support and inspiration underpour overpour ­ in eye Notice at the ends where the strain was CUTfrom the pontil ... most are ground off at the ends AWNING RINGS ... They were NOTdesigned to be an insulator ... BUTwere sometimes used as radio strains What are they? We sincerely hope that those of you who have ever said "WHAT IS A STRAIN?" or "WHAT DOES A STRAIN DO?" ... will be able to answer that question now and be able to recognize a strain the next time you see one. T HANK Y OU!! Charles and Sandi Irons P
POONNTTIILL GGLLAASSSS ­­ Notice a piece of the eye of a strain still attached from when it was poured. 2'' 2¼'' CUT