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INTRODUCING OPAR- The One Person Antenna Raiser
by John Reisenauer,
Jr., KL7JR (Updated with newer compact version
01-08-09) See end of article
Like to
operate portable? Do you have trouble finding help for antenna raising at
your QTH? This may just be the answer for you.
You can drive a
vehicle on the base for portable operations or mount permanently at your
QTH by bolting base to concrete inserts. Slip the mast in the base of OPAR
(short pipe section tilts), mount your antenna and hoist up all alone.
Mast easily secures in place with moveable locking bolt and large spanner
nut. Guying methods should also be employed for heavier antennas. I've
used OPAR to lift small beams, verticals, rigid dipoles and various wire
antennas to heights of 20-30 feet with minimal effort all by
myself!
 OPAR shown above set up ready to accept antenna
mast. Simply insert mast end in to OPAR pipe stub, install antenna and
raise.
 OPAR shown
above with antenna raised and mast locked in
place.
Although OPAR is
designed for "one-person operation" using small to medium sized antennas,
it's always good safety practice to have help on hand. OPAR as pictured is
considered "medium-duty" use. Several variations (use your imagination for
your own particular use!) exist (ie-length of vertical or horizontal
members, etc.) depending on your specific use. A flexible design is what
makes OPAR more "user friendly" compared to the commercially made models.
For larger antennas or operating in the Arctic, I'd recommend adding a
second vertical brace higher up on the vertical section and adding at
least another 12 inches or more to the overall height (36 to 48 inches
plus). If you are not an experienced welder, it's best to have a
professional welder do the welding (the number of "good welds" is directly
proportional to the length of time the antenna and mast stays in the
air!). My OPAR cost about $340 to make locally. Raising a tri-bander alone
is not easy especially for the inexperienced Ham, but it is possible if
done correctly. Remember to have help on hand if at all possible. I wished
I had OPAR many years ago! Good luck with your antenna projects.
MATERIALS LIST (medium duty
OPAR)
- vertical
support 36 inches tall by 9 inches wide w/support braces every 6 to 8
inches.
- horizontal support (drive-on) same as above.
- 1
inch OD square tube steel used (approx. 20 feet total required) for
strength vs. round stock.
- 1/2 inch x 3 inch long bolt with welded
spanner nut
- mast hinge is ½" pipe by 6 inches long inside two ¾'
pipe sections.
- 3/8 inch by 2" wide plate used to secure mast to
top of vertical support.
Some economical mast materials used by KL7JR:
1. Light-duty use: Chain link fence "top
rail" pipe or EMTconduit for smaller light weight antennas.
2.
Medium to Heavy-duty use: IMC threaded conduit
or galvanized threaded water pipe (1 ¼" size works great).
New Updated Compact Version!


I've been kicking this simple design
above around for some time. It's smaller and lighter than my
original
OPAR (one person antenna raiser) seen
above, and only cost $50 (2009 prices), for a welding shop to
make for me.
Quarter-inch plate and 1/4"x4"x3"
angle. Modify it to your own design as you wish! CQ DX here we
come! ENJOY!
DISCLAIMER Feel free to copy or modify
this design at your own risk. Neither USI, NCDXA nor KL7JR claim any
responsibility.
73 de Yukon John,
KL7JR
KL7JR@arrl.net
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