WCARC
2 Meter
Slim Jim
PVC Pipe J-Pole
Antenna Project
2/4/2017 WCARC Club Projectd
Bill Sepulveda, K5LN
1
300 Ohm Feed Line Slim Jim J-Pole Antenna
Materials:
QTY
1
1
2
1
1
1
1
1
Description
12” Nylon Kite String
3/4” Schd 40 PVC Pipe (Thin Wall 5 FT long)
3/4” Square Ended PVC End Caps
3/4” PVC In-Line Splice
60” 300 Ohm Feed Line
3/8” dia., 1/2” long Heat Shrink tubing)
3-1/2” piece of RG-58 Coax
BNC Female Connector 1/2” Thread w/ground
2/4/2017 WCARC Club Projectd
Bill Sepulveda, K5LN
2
300 Ohm Feed Line Slim Jim J-Pole Antenna
Make PVC Parts first.
3/4” In-line splice
Cut slot in Splice
with Hack Saw
Inside center stop ring
must be removed
to slide over pipe
easily.
This In-Line splice is used
to support the mounting of
the antenna with the same
diameter as the End Cap.
Views are not to scale!
Reference only!
2/4/2017 WCARC Club Projectd
Bill Sepulveda, K5LN
3
300 Ohm Feed Line Slim Jim J-Pole Antenna
Make a small holes using an Exacto Knife. Cut 12” of Kite string and tie off.
Measure 58-9/16” from inside of bottom wire to the top of the Feed Line, and cut
off excess. Remove a 1/2” of insulation from the wires at the top of the Feed
Line. Fold wires over just like the bottom. Solder, and remove excess.
300 Ohm Feed Line cable.
5
2
34-3/4”
Make PVC parts first!
Dotted lines are wires inside Feed Line.
The dimensions
are based on the
antenna being
mounted in the
five foot length of
Sch. 40 PVC Pipe.
3
10
Cut out notch. Just enough to remove the wire. (34-3/4” & 15”) Remove the wire
between the cuts.
See Tuning section for Tuning and Final Assembly.
TO START, CUT THE FEED LINE TO A LENGTH OF 60.00”!
58-1/16”
4
Dimension is from Inside of wires at both ends.
Cut out small notches to expose both wires (DO NOT CUT WIRES).
15”
1/8”
1/4”
7
Assemble End Cap and solder Coax to BNC connector.
8
6
Solder coax leads to wires in center of notch. Important: attach the shield lead to
the antenna as shown!
Use heat shrink tubing or tape to hold coax flat against bottom of cable.
Do this before adjusting antenna SWR.
9
1-7/8”
1
View is not to scale!
Reference only!
6
1/4” 3/8”
2/4/2017 WCARC Club Project
Strip 1/2” from end of antenna, Fold wires over flat so they are side-by-side.
Solder and remove excess.
Use 3-1/2” of 50 Ohm RG-58 Coax. Antenna end outer sleeve is stripped to 3/8” w/center
stripped to 1/8”. 5/8” outer sleeve is stripped from the other (connector) end, with an 1/8”
cut off from the center lead, and an 1/8” center insulation removed. Form both ends to
match the drawing, twist, and tin all leads.
Bill Sepulveda, K5LN
4
300 Ohm Feed Line Slim Jim J-Pole Antenna
Step
7
View is not to scale!
Reference only!
Drill hole in
center of End
Cap for BNC
connector.
Apply small bead of
RTV around hole
before inserting BNC.
NOTE:
Tin both Leads on the
BNC connector prior to
assembling to End Cap.
2/4/2017 WCARC Club Projectd
Bill Sepulveda, K5LN
5
300 Ohm Feed Line Slim Jim J-Pole Antenna
String on end of Feed Line
Step
10
Testing:
Trim antenna to read best SWR at
146.000MHz +/- 100 KHz.
Long
Short
View is not to scale!
Reference only!
After the antenna assembly is completed, install
the antenna into the PVC pipe and secure the
End Cap with the BNC connector to the bottom
of the five foot pipe. Pull the string on the end
of the Feed Line over the edge of the top of the
PVC pipe. Install the other PVC End Cap over
the string, pinching the string between the pipe
and End Cap.
TUNING:
SWR and Frequency are adjusted by trimming at
this area. Important; make adjustment using a 3
to 1 ratio when material is removed. This means
adjustment
inthe
if a 1/16” is removedMake
from this
the Short
side of
smallthat
steps.
Not
greater
than 1/16”
Cuts!
“J”,
3/16”
must
be removed
from
the Long
side of the “J”. Do not remove more than 1/18”
at a time from the Short side.
After the antenna is tuned, the Top and Bottom
End Caps may be sealed by using Clear RTV
around the edges.
2/4/2017 WCARC Club Projectd
Bill Sepulveda, K5LN
6
2/4/2017 WCARC Club Projectd
Bill Sepulveda, K5LN
7
Alternative Mount for the Water Pipe J-Pole Project