The 137CP14HD is a mid-sized, performance circular polarized antenna with a remarkably clean pattern. The pattern is
important in order to match the antenna’s noise temperature with modern low noise preamps. This antenna is ideal for
satellite communications. The CNC machined driven element module is O-ring sealed and weather tight for low maintenance and long-term peak performance. Internal connected are encapsulated in a space-age silicone gel that seals out
moisture and improves power handling. The 3/16” 6061-T6 rod elements are centered to minimize interaction and maintain good ellipticity. Insulators are UV stabilized and locked in place with stainless keepers. Rugged construction, uncompromising performance: that's the M
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137CP14HD
M2 Antenna Systems, Inc. 4402 N. Selland Ave. Fresno, CA 93722
TOOL REQUIRED FOR ASSEMBLY: Screwdriv er, 11/32 nut driver or wrench, 7/16” and 1/2” end
wrenches, pliers, measuring tape.
1. Start by laying out the boom sections, noting hole positions and matching to the DIMENSION
SHEET.
2. If you are also using the M
right. Loosely install an 8-32 x 1-1/2" screw and locknut into
the clamp fingers. Then slide the clamp on the rear boom
section (1"). Do not tighten clamp at this time.
3. Separate elements by length into two sets, “H” (rear) and
“V" (forward). Offset between the two element sets is 1/4
wavelength. Follow the DIMENSION SHEET lengths carefully because SETS ARE NOT IDENTICAL. Lay out the “H”
element set by length and position as shown on the DIMENSION SHEET. Begin with the reflector
(longest) element. Balance it across your finger to find rough center and push on a black button
insulator to about 1/2” off center.
INSTALLATION TIP FROM MIKE: Because of tolerance in rod diameter, use pliers or equivalent
to deform the hole in both button insulators until the rod fits through each tight. This will help
hold the elements firmly in place and make it easier to hold the element on center during
KEEPER installation.
Insert the element through the hole and install the second button, snugging it up into boom. DO NOT
BOTHER TO ACCURATELY CENTER the elements at this time and DO NOT INSTALL the stainless
steel shaft retainers. This is easier to do after ALL the horizontal elements are installed in the boom.
4. Install the 3/8” tube DRIVEN ELEMENT as you did the reflector. Then continue with the installation
of the DIRECTORS. Note that the Director Elements do not consistently diminish in length from rear to
front, so pay close attention to length and position.
5. Now begin centering the elements. Use a tape measure to EQUALIZE the length of rod showing
on each side of the boom within 1/16 inch. Once you have all the elements centered, sight down the
element tips from the rear comparing each side. Look for any obvious discrepancies and correct, if
found.
6. INSTALLING THE SHAFT RETAINERS: Deburr or champher the inside edges of the PUSH
TUBE (3/8" x 3" tube, supplied in the kit) to allow the retainer fingers to flex into the tube during
installation. Use thumb and forefinger to hold the retainer over the end of the Push Tube with the
internal fingers on retainer dished into tube. HOLD THE ELEMENT FIRMLY TO PREVENT IT FROM
SLIDING OFF CENTER and press the retainer onto the element end and continue until retainer butts
on insulator button. Locking pliers, lightly clamped up against opposite button insulator will help
maintain center reference (if you push the first retainer too far, remove element from boom, push it
completely off the element, and start over). Install another retainer to the opposite side of the element.
Continue installing retainers until all elements are locked in place.
NOTE: The SHAFT RETAINERS (used in securing the elements) should always be used for
permanent and long term antenna installations. For portable or temporary use, or whenever it is
anticipated that the antenna will be disassembled within a short time, the retainers may be left off. The
button insulators, normally a tight fit, hold the elements quite securely.
2
H-frame Kit, open that kit and find one of the 'T' brace clamps shown at
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137CP14HD ASSEMBLY MANUAL
7. Mount the HORIZONTAL DRIVEN ELEMENT BLOCK / ROD ASSEMBLY to the TOP of the boom
using a single 8-32 x 1-3/4" screw. Orient the block with the two Balun connectors facing to rear.
Install the 8-32 x 1/4” set screws (internal Allen head – tool supplied) into the SHORTING BARS.
Slide the bars onto the 1/8”" driven element tubes and the 1/4" Driven Element Block Rods. Position
the Shorting Bars as specified on the DIMENSION SHEET. The given dimension is between the outer
face of the driven element block and the inner face of the shorting bar. Align the bars with each other
and tighten the set screws. (SEE PHOTO BELOW)
8. ASSEMBLING THE VERTICAL ELEMENTS: Repeat steps #2 through #5 for the Vertical
(forward) elements, using the DIMENSION SHEET as your guide to lengths and spacing.
9. INSTALLATION OF THE VERTICAL DRIVEN ELEMENT BLOCK: Refer to the DIMENSION
SHEET for block orientation and Balun direction. All driven element blocks in the final array must
be mounted in the same position – such as all horizontal driven element blocks up with Balun to
the rear and all vertical blocks on the same side with the Balun going to the rear. Install the
shorting bars as specified on the DIMENSION SHEET. (SEE PHOTO BELOW)
D.E. BLOCK
SCREW, 8-32 X 1-1/4”,SS
PHAS LINE
1/4 WAVE
D.E. BALUN
D.E. BALUN
JUNCTION BLOCK
SCREW, 8-32 X 1-1/4”
D.E. BLOCK
SCREW, 8-32 X 1-1/4”,SS
10. Before installing the Baluns, thread 3/8” SEAL NUTS fully onto all connectors, with the black
Neoprene side facing out. Attach Baluns to the Driven Element Blocks connectors as shown on the
drawing. Coil rear Balun once to keep length on boom. Tighten the connectors gently using a 7/16"
end wrench. Once the connectors are tight, back the Seal Nuts out and finger-tighten firmly up against
the face of the connectors (or tighten gently with 1/2” end wrench). A lot of torque is unnecessary.
The Vertical Balun may loop around a horizontal element. This is normal. Form Balun coax close to
the boom and secure with nylon cable ties. Ties should be snug, but not crushing or kinking the coax.
11. Use top quality coax and “N” connector for your phasing / matching lines. If using with the M
-frame Kit, secure coax near feed connectors on driven element blocks, to provide stress relief, route
to 'T' brace clamp, and down 'T' brace tube to power divider. Secure at regular intervals. Refer to HFrame Manual for important details on orientation of antennas: driven elements must be correctly
phased. In homebrew arrays, phasing / matching lines should at least exit from the boom behind, and
parallel to, the forward reflector and at right angles to, and slightly forward of, the rear-most driven
element. Another alternative is to have both lines exit at the rear of the boom. Do not route lines
forward to boom-to-mast plate as exiting antenna, in any plane, here will adversely affect
pattern.
PHASE LINE
3/4 WAVE
2
XP H
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137CP14HD ASSEMBLY MANUAL
12. The boom to mast plate. (SEE DIMENSION SHEET). The plate on each antenna should be
mounted at the identical location. When used in an array, the rear 'T' brace, coax, and power dividers
add considerable weight to the rear of the antenna. When used with an M
elements are aligned with the boom to mast plate. Secure plate with two 2" U-bolts and the stainless
nuts and lock washers provided. DO NOT OVER TIGHTEN. 2” and U-bolts and stainless hardware
are provided for mounting the antenna to a NON-CONDUCTIVE mast or crossboom.
13. The 137CP14HD ANTENNA creates a field in all planes or polarities. PERFORMANCE
DETERIORATES SIGNIFICANTLY if it is mounted to a metal (conductive) mast / cross boom or if the
feedline exits the boom anywhere but at the rear. A 2” mast of any NON-CONDUCTIVE material can
be used. Fiberglass is the prime choice for its strength and weather resistance. Array hardware that
does not intersect or intrude on the element planes may be of conductive material; for instance, the
main crossboom in a 4- or 8-bay array or the center 5-6 feet of the vertical support masts.
14. Orientation of multiple antennas in an array is critical to optimum performance. If using with See
the attached array harnessing, spacing, and hardware arrangement drawing if using with the M
frame Kit. (PLEASE SEE H-FRAME MANUAL FOR MORE INFORMATION)
M2 ANTENNA SYSTEMS, INC.
4402 N. SELLAND AVE.
FRESNO, CA 93722
(559) 432-8873 FAX: 432-3059
www.m2inc.com Email: sales@m2inc.com
2
H-frame Kit, vertical
2
H-
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137CP14HD PARTS & HARDWARE
DESCRIPTION QTY
#1 BOOM SECTION, 1-1/2 X .058 X 60” SOE .................. 1
#2 BOOM SECTION, 1-1/2 X .058 X 56” SOE ................... 1
#3 BOOM SECTION, 1-1/2 X .058 X 32” STR ................... 1
ELEMENTS, 3/8 Tube X Dimension Sheet ...................... 14
DRIVEN ELEMENT BLOCK ASSEMBLY .......................... 2