Steren ANT-UHF 20 Manual De Instrucciones página 31

7.- There are two channels in the base, where you will attach the longest
element.
Remove the screw and nuts: first insert the part where there are two holes,
put the screws to adjust; then place on the other channel and install the screw.
8.- Attach the bracket for the mast
(not included) in the bottom for the
antenna.
9.- To finish the assembling,
insert the A-type and B-type
arms to the base.
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