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Old 09-28-2012, 03:18 PM
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DavGoodlin DavGoodlin is offline
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Join Date: Aug 2011
Location: near Strasburg PA
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JFD - Frankenstein of Antennas part 1 of 2

Last week, I climbed up into the darkness of the garage attic and pulled out a rather interesting UHF helical I snagged off a 3-story roof several years ago. JFD Zig-a-log.jpgI had attempted to get one of these several times only to be turned away by the queasy, litigation-shy and just plain ignorant to the $20 spot I offered. Breaking out WD40 for frozen wingnuts and emery cloth shined up harness connections for maximum conduction. I then climbed the tower and hoisted my Zig-a-log (LPV-ZU20) into place, connecting through the CM7777 mast amp, expecting some record-breaking performance. I was not disappointed. It was a tad less effective than the Jerrold, but had a significantly narrower beam. Again, nothing beats a parabolic CM4251 for UHF.

Update 10/1/12: During changeable rainy weather yesterday, the ZigaLog seemed to perform better on the "difficult channel WPPX" as the weather worsened. All the while the parabolic, located 40 feet away and at a lower elevation was having trouble holding the channel as is the norm during such weather.

Few antenna manufacturers of the glory days made their products as easy to identify as JFD. Originally JFD of Brooklyn NY seemed to make only signal splitters, couplers and other TV accessories. I have a few examples of those items and the boxes they came in. I have a few catalogs (out on loan) that covered much of JFD's late 1950s product line.
Here is an example of JFD's top-value UHF antennas that most manufacturers made, the 4-bay bow tie and corner reflector plus a mid-60s advertisement for JFD expressing frustration over a 1965 government mandate for all-channel TV stopping short of addressing antennas. Sound familiar? JFD Ad 2.pdf

This ad proclaims a breakthrough VHF design noting 6 patents which would be a formidable competitor for the next 15 years! Many of these are still visible on rooftops due to rugged construction.JFD Ad 1.pdf

This ad includes the "trapezoid" or helical design UHF antenna in a set-top version. My next post will feature a home-made replica of this little UHF wonder based on a 1970 JFD antenna I am still using. as a VHF performer. Hopefully, you can read the paragraphs supporting the "fight" against CATV coming to your area JFD Ad 3.pdf

J F D Antennas were usually so well-constructed, many can still be seen today. The tell-tale mid-element capacitors optimized high-band performance. They also had the most bizarre lookwith Channel Master coming in a distant second in that category.

The antenna pictured JFD LP VU.jpgis one of the last LPV models JFD made before becoming history. A search of JFD turns up little more than a patent infringement suit with Channel Master and a superfund site in NC.

Last edited by DavGoodlin; 11-02-2012 at 02:04 PM. Reason: Add ads and
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