Rescue Electronics Surplus
Manufactured by Paul A. Cianciolo W1VLF Email PaulC@snet.net with inquiries
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FM Log-Periodic FM Antenna
Electrical Specifications:
- 8 Elements covering 88 MHz to 108 MHz with better than 8DBi gain across the band. This true free space gain, and does not include the additional 6 db of ground
gain included in some others antenna meadurements.
- Antenna Input Impedance 75 Ohms
- Front to Back Ratio is very high at 25 to 30 DB across the band.
- Return Loss commonly, referred to as SWR, is 1.5 to 1 across 88 MHz to 108 MHz
- These values were verified using both computer aided modeling and real world measurements made at my lab.
Physical Specifications:
- Antenna Weight 11 Lbs
- Wind survival greater than 80 MPH
- Boom Length is 8 feet
- Boom Material is 2 of 1" square .090" wall 6063 aluminum tubing in parallel.
- Elements are made from solid .25" 6061-T6 high strength aluminum
- Longest element 68.5"
- Shortest Element 38.0"
- Elements are bolted to the boom with stainless steel Nylock nuts to prevent them from ever loosening up.
- Mounting bracket is .5" high strength UV protected polycarbonate attached to the boom using 6 stainless countersunk bolts.
- The mount is fitted for a 2" diameter mast but on request can be customized for 1.5" mast
What's In The Box ?
- The antenna will be shipped to you in a 96"x 8" x 8" box. This is because the boom is completely assembled when you receive it.
- Your job will be to attach the elements, attach the feed line, and mount the antenna. Tools needed for the job will be a 7/16" wrench, 9/16" wrench and a common
pair of pliers. You will want to have some electrical tape handy to waterproof the F connector.
- The elements are clearly marked as to their location on the boom. Simply insert the element into the corresponding hole and tighten the NyLock.
- Total assembly time under 30 minutes.
Why Buy This Log Periodic Antenna?
- I build these Log Periodic antennas from the highest quality materials so they will work exceptionally well, and also tolerate the high winds, rain, ice loading that we
get here in New England.
- The log periodic really excels at front to back ratio and front to side ratio.
- This is very important in the FM band and allows for excellent rejection of unwanted stations, and, allows you to hear the station you want.
- When analyzed by computer software the antenna shows an ave of F/B ratio 25 DB to 30 DB My off air measurements with a spectrum analyzer have confirmed
these numbers.
For example at my house in Harwinton CT I can listen to either WGBH Boston MA, WTBR Pittsfield MA. or WFGB Kingston NY just by moving the antenna direction.
All these stations are on 89.7 MHz and range from 50 to 120 miles away from my house.
Final Comments:
This a great performing antenna that is ruggedly designed to withstand the snow, icing and winds, of New England winters.
Shipping costs restrict this antenna to be sold in the 48 contiguous states
8 Element FM Broadcast Heavy Duty Log-Periodic antenna
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For purposes of clarity some of the elements and various components have been removed in the following pictures
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Click on thumbnails for full sized pictures
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Antenna Polar Plots & SWR Curve
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Antenna Connector can be a female UHF upon request.
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