- A center post with internal wiring protected from moisture and sun can be built using split PVC
conduit designed for conduit repair. After the terminals and coax connections are installed, the two
sides snap together or slide together for a weather proof center post. They can be taken apart later
for adding bands such as six meters.
- While it is not necessary, you can spray paint the center post and pvc cap. The cap has an eye bolt
installed as an anchor for the radial support cords.
- RG 213 coax is used for power capability at the legal limit
- The coax connector is located at the bottom but inside the center post it feeds the driver wires at
the top with the 20 meter band first and 10 meters last for best performance.
- You can still use an external feedline harness on a 1.25" diameter fiberglass tube if you prefer that
to the center post arrangement illustrated here.
Hexagonal Beam by K4KIO
Building the G3TXQ Broad Band Hexagonal Beam
Available for purchase
Buy or build a hex beam
Other Sites
Understanding the
Hexbeam byG3TXQ
Yahoo hexbeam user
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G3TXQ Broad Band Hex
Beam built by WY3A
Understanding the
Hexbeam byG3TXQ
Yahoo hexbeam user
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G3TXQ Broad Band Hex
Beam built by WY3A
Six Steps to build it - Center post
Parts needed
Tools needed
Hacksaw
Straight edge
Measuring tape or ruler
Drill and assorted bits
Screwdriver, med.
Wire cutter/stripper
Small wrench
Soldering iron
Solder
Felt tip marker
Straight edge
Measuring tape or ruler
Drill and assorted bits
Screwdriver, med.
Wire cutter/stripper
Small wrench
Soldering iron
Solder
Felt tip marker
|
Click these photos to enlarge
Finished product
Measure and mark 1 7/8
inches on one end and 1" on
the other and then with either
a jig saw or a hack saw, trim
off the overlaps on the two
pieces of split conduit. This
will allow the center post to
slip down into the flange on
the base plate and the cap to
slip on the top of the post.
If you want to paint the center
post, now is a good time to do
it.
inches on one end and 1" on
the other and then with either
a jig saw or a hack saw, trim
off the overlaps on the two
pieces of split conduit. This
will allow the center post to
slip down into the flange on
the base plate and the cap to
slip on the top of the post.
If you want to paint the center
post, now is a good time to do
it.
Measure and mark holes to
drill in one of the conduit
sides that will be the front. All
terminal holes and the coax
connector will be on the front.
There will be no hardware
installed on the back side as it
must be able to slip up and
down for disassembly.
Holes to be drilled are for 10
terminals, one SO239 and the
two mounting bolt holes for it.
drill in one of the conduit
sides that will be the front. All
terminal holes and the coax
connector will be on the front.
There will be no hardware
installed on the back side as it
must be able to slip up and
down for disassembly.
Holes to be drilled are for 10
terminals, one SO239 and the
two mounting bolt holes for it.
After drilling the holes, install
the SO239 with a lug on one
bolt for the coax braid and all
the terminals with lugs as
shown. Tighten with the lugs
lined up and down the post for
inserting the coax.
Install pieces of coax between
the terminals with all braid
connections on the same
side. Do not mix from terminal
to terminal as it will adversely
affect performance.
the SO239 with a lug on one
bolt for the coax braid and all
the terminals with lugs as
shown. Tighten with the lugs
lined up and down the post for
inserting the coax.
Install pieces of coax between
the terminals with all braid
connections on the same
side. Do not mix from terminal
to terminal as it will adversely
affect performance.
After all terminals are
interconnected, install a
single long coax piece from
the top terminal (20 meters)
down to the SO239 coax
connector. After soldering,
you will find that the terminal
bolts all need re-tightening as
they sink slightly into the pvc
because of the heat of the
solder gun.
Drill a hole in the pvc cap
and install the eye bolt.
interconnected, install a
single long coax piece from
the top terminal (20 meters)
down to the SO239 coax
connector. After soldering,
you will find that the terminal
bolts all need re-tightening as
they sink slightly into the pvc
because of the heat of the
solder gun.
Drill a hole in the pvc cap
and install the eye bolt.
Before sliding the sides
together, make a simple DC
short/continuity check to make
sure no unseen braid strands
are shorting across the coax at
the terminals.
The sides can be slid
together. No adhesive is
needed. Notice the
reinforcement piece glued in
the bottom where the flange
set screws will apply pressure.
together, make a simple DC
short/continuity check to make
sure no unseen braid strands
are shorting across the coax at
the terminals.
The sides can be slid
together. No adhesive is
needed. Notice the
reinforcement piece glued in
the bottom where the flange
set screws will apply pressure.
| Site publication date 12/2007 Page revision date 9/2009 Copyright 2009 |
Split conduit can be obtained from www.conduitrepair.com
but is fairly expensive. The other hardware is obtainable
from local hardware outlets.
A fine alternative is to use a 1 inch PVC Schedule 40 pipe
and mount external terminals on the sides at the
appropriate heights for each band and connect between
them with 50 ohm coax. See photos below for this.
but is fairly expensive. The other hardware is obtainable
from local hardware outlets.
A fine alternative is to use a 1 inch PVC Schedule 40 pipe
and mount external terminals on the sides at the
appropriate heights for each band and connect between
them with 50 ohm coax. See photos below for this.
Table of contents
General
Overall Description
Broadband vs Classic
Six Steps to Build It
The Parts
The Mast
Specs and FAQ's
SWR Results
General
Overall Description
Broadband vs Classic
Six Steps to Build It
The Parts
The Mast
Specs and FAQ's
SWR Results
If you don't want to pay the premium price for the split conduit used above, you can fashion a perfectly good center post using an external feedline. Just get a piece of
Schedule 40 pvc, 1 inch from Lowes and attach terminals as shown below. There are two ways I have used successfully to make terminals. One is to fish bolts down the
inside of the center post and through holes drilled. You can use a clothes hanger wire with the end bent back double to hold the bolt. Then, when you have this done,
just connect all the terminals with coax and seal it from rain so the coax doesn't soak in any moisture, a killer for performance.
Another approach for external terminals is to use Euro terminals that can be gotten at Radio Shack or Mouser.com. Just mount them to the post with a 1 1/2 inch #40
bolt and you are off to the races. See the photos below for illustrations on these two low tech approaches.
Schedule 40 pvc, 1 inch from Lowes and attach terminals as shown below. There are two ways I have used successfully to make terminals. One is to fish bolts down the
inside of the center post and through holes drilled. You can use a clothes hanger wire with the end bent back double to hold the bolt. Then, when you have this done,
just connect all the terminals with coax and seal it from rain so the coax doesn't soak in any moisture, a killer for performance.
Another approach for external terminals is to use Euro terminals that can be gotten at Radio Shack or Mouser.com. Just mount them to the post with a 1 1/2 inch #40
bolt and you are off to the races. See the photos below for illustrations on these two low tech approaches.
Click these photos to enlarge
Other approaches
Click these photos to enlarge