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I OBTAINED THIS QUALITY PORTABLE MULTI-BAND TOP LOADING ANTENNA SYSTEM WITH A GROUP OF HAM RADIO EQUIPMENT, SOME OF WHICH I PLAN TO KEEP BUT ALREADY HAVE A GOOD DIPOLE SO DECIDED TO LET SOMEONE ELSE HAVE THE PORTABLE. JUST DON'T THINK I'LL USE IT. THIS IS OBVIOUSLY A WELL CRAFTED ANTENNA USING STAINLESS STEEL AND BRASS FITTINGS ALONG WITH VERY HEAVY SHRINK-WRAP PLASTIC AROUND THE LOAD COILS. THE ONLY LABEL I SEE ON IT HOWEVER IS A TAG ON THE 20 METER TOP SECTION "CUSTOM ENTERPRISES BARRY W9UCW & JOYCE WB9NUL RT #6 BOX 748A HARLINGTON TX 78552. BARRY ALSO WROTE HIS NAME AND CALL SIGN ON A COUPLE OF THE SECTIONS. ONE OF THE PICTURES SHOWS HOW ALL OF THE TOP BAND ELEMENTS CAN BE ATTACHED TO FITTINGS AROUND ON OF THE MAST SECTIONS FOR STORAGE. EACH OF THE BOTTOM SECTIONS IS ABOUT 48 INCHES. HERE ARE THE DIMENSIONS OF THE BAND-SPECIFIC TOP SECTIONS (APPROXIMATE MEASUREMENTS): 10 METER: COIL 2.5 INCHES - SHAFT 3 INCHES - WIRE 9 INCHES - OVERALL 16.5 INCHES 15 METER: COIL 4.25 INCHES - SHAFT 3 INCHES - WIRE 11.5 INCHES - OVERALL 20.5 INCHES 20 METER: COIL 8.5 INCHES - SHAFT 3.5 INCHES - WIRE 14.5 INCHES.- OVERLL 29 INCHES 40 METER: COIL 10 INCHES - SHAFT 12 INCHES - WIRE 12.5 INCHES - OVERALL 37 INCHES 80- METER: COIL 8.5 INCHES - SHAFT 12 INCHES - WIRE NEGLIGIBLE - OVERALL 25 INCHES - 3 LOBE HAT EACH LOBE 9.5 INCHES OUT I AM GUESSING THAT THE TOP WIRES ARE ADJUSTABLE FOR PURPOSE OF FINDING BEST SWR. WHETHER OR NOT ONE MAST SECTION SHOULD BE USED INSTEAD 2 FOR THE HIGHER FREQUENCIES (SAY 10 METER) IS A POSSIBILITY BUT I DON'T KNOW. GUESS WHAT KIND OF SWR YOU GET MIGHT DETERMINE THAT OR YOU MIGHT BE ABLE TO GET MORE INFO FROM W9UCW I DON'T KNOW . HAVEN'T BEEN ABLE TO FIND ANY DOCUMENTATION ON THIS ANTENNA. I'LL NEED TO REMOVE THE "HAT" (3 OVAL WIRES) ON THE 80 METER BEFORE MAILING. IS VERY EASY TO PUT BACK TOGETHER. FOR WHAT ITS WORTH HAVE BEEN DOING SOME BOOK-LEARNIN ON SHORT ANTENNAS. THE ARRL HANDBOOK INDICATES THAT A SHORT TOP LOADED ANTENNA LIKE THIS WOULD REQUIRE SOME SORT OF MATCHING CIRCUIT BETWEEN THE TRANSMITTER AND IT. "A parallel Tuned Circuit indepenently resonant at the operating frequency is required for coupling to the transmitter when the top loading is adjusted to bring the current node at the lower in of the antenna". IE MOST LIKELY DON'T HOOK THIS ANTENNA DIRECTLY TO YOUR TRANCEIVER WITHOUT THE SUGGESTED COUPLING CIRCUIT. ( ham vertical mult-band radio antenna 10 15 20 40 80 was posted and is owned by: Elnora Steele) |
Elnora_steele@chicagopartsnetwork.com (Elnora Steele) for more information.
