Anyone ever heard of J-BEAM or SLOT-BEAM Yagi antenna's?
I have one here, it's quite an oldie. The one I've got is a 18 element
(including driver and reflector) for 70 cm. The driver looks lika a kind of
'stacked folded dipole':
2 Meter Skeleton Slot Antenna Booster
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Years ago, I had a home brew skeleton slot feeding 2 each 8-element 2-meter yagis that was built based on the designs in the RSGB VHF Handbook. That antenna worked very well. However, I have never tried a skeleton slot below 144 MHz. Incidentally, this is a great antenna for 2-meter repeaters, which require vertical polarization. The copper pipe loop portion of the skeleton-slot antenna is the equiva- lent of the solid plane in a classical slot antenna with the vertical space between the loops forming the slot. I believe this antenna is a result of the efforts of the Belgrad radio amateurs to create an improved antenna for working 2 m EME. With the K8AT skeleton slot driven double boom Yagi as a starting point. As the K8AT antenna.
The two 'dipoles' are not 180 degrees but slightly less:
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2 Meter Skeleton Slot Antenna Adapter
The reflector is similar shape as the driver, but both 'dipoles' are in a
straight line (180 degrees).
2 Meter Skeleton Slot Antenna Booster
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Strange things are: all the directors are of the same length and the width
is bigger than the dipole/reflector width. The dipoles seem a bit small
comparing to a ordinary folded 70 cm dipole. At first I thought it was an
antenna for higher frequencies, but the guy I bought it from ensures me he
used it several years for 70 cm (I believe him! He's a nice guy and I got
the stuff for 'an apple and an egg' so why should he lie?). I don't know
exactly what kind of balun I should provide this beauty with? It's got a
balun inside but it's a bit rosty so want to replace it by a new one.
Indian casino needles ca.
I cleaned the aluminum (it's nice and shiny now, like new). It's a very
impressive antenna. but does it WORK? Anyone got any info on it while I'm
working at the 3-meter-boom-beast?
2 Meter Skeleton Slot Antenna Receiver
Please reply ONLY via email to: PD1..@AMSAT.ORG
2 Meter Skeleton Slot Antenna Combo
73, Pleun
2 Meter Skeleton Slot Antenna Tuner
P.S. (Dutch): Dit bericht was in het Engels omdat ik het ook in andere
internationale newsgroepen heb gepost. Als iemand informatie heeft over de
J-beam of Slot-beam en het bericht niet helemaal begrijpt dan wil ik gerust
even een vertalingkje sturen.
