LA2QAA POCKET BEAM.
I needed a small aerial that was rather less conspicuous than the infamous Arrow.
The two pictures should be self explanatory.
'INGREDIENTS' ... (parts required).
270mm length of thin walled aluminium tube ... (my other! crutch).
2 x BNC chassis connectors ... shorted together.
20cm thin-walled fibreglass tube ... MUST BE BLACK ... (GM1SXX will explain why).
30cm RG-58 terminated in a BNC connector.
2 x transistor radio telescopic whips.
2 x 100mm x 2mm silver plated copper wire. (Tinned copper wire will work as an alternative.)
2 x hose-clamps.
2 x ferrite tubes.
File handle ... (optional).
For the driven element, the coax is connected to two of the whips in a split boom
configuration with a hairpin match. A hose-clamp is slid along the boom for shorting
the hairpin. The other hose-clamp is glued to the optional file handle for holding the
beam.
'Nominal' measurements are ...
Driven element = 940mm.
Reflector = 1040mm.
Spacing = 260mm.
Hairpin match = 60mm.
NOTE THE TWO FERRITE TUBES 1/4 WAVE FROM THE FEED-POINT.
The measurements are 'interactive'.
Mini-beam (folded)
Mini-beam (Assembled)
73 LA2QAA. <la2qaa@amsat.org>