M2 Antenna Systems 418CP30 User manual

M2 Antenna Systems, Inc. 4402 N. Selland Ave. Fresno, CA 93722
Tel: [phone] Fax: [phone] Web: www.m2inc.com
©2018 M2 Antenna Systems Incorporated 5/14/19
REV B
M2 Antenna Systems, Inc.
Model No: 418CP30
FEATURES:
The 418CP30 is a practical sized, yet high performance circular polarized antenna with a remarkably
clean pattern. The versatile pattern is important in order to match the antenna’s noise temperature with modern
low noise preamps. This antenna is ideal for commercial LEO satellite work and was designed with a second res-
onance band at amateur frequencies of 335-338 MHz, with a peak gain of 16 dBi. The CNC machined driven
element module is O-ring sealed and weather tight for low maintenance and long-term peak performance. Inter-
nal connected are encapsulated in a space-age silicone gel that seals out moisture and improves power han-
dling. The 3/16” 6061-T6 rod elements are centered to minimize interaction and maintain good ellipticity. Insula-
tors are UV stabilized and locked in place with stainless keepers. Rugged construction, uncompromising perfor-
mance for the boom length: that's the M2 418CP30!
Model ................................. 418CP30
Frequency Ranges* ........... 414-427/435-438 MHz
Gain**.................................. 16.0 dBi
Front to back ....................... 21 dB Typical
Ellipticity .............................. 1.5 dB Typical
Beamwidth ........................ 35o circular
Feed Impedance. ................ 50  , Unbalanced
Maximum VSWR................. 1.7:1 Max
Input Connector .................. “N” Female
Power Handling ..........................600W
Boom Length / Dia......................128.5” / 1" Dia
Longest Element.........................13.75”, 3/16" Rod
Stacking Distance.......................50”
Mast Size....................................1-1/2”/ 2”
Wind area / Survival .....................1 ft.2/ 120 mph
Weight / Ship Wt.........................5 lbs. / 7 lbs. UPS
SPECIFICATIONS:
*Dual Band Resonance **Subtract 2.14 from dBi for dBd

TYPICAL TOOLS REQUIRED: measuring tape, phillips screwdriver, 5/16”, 11/32”, 7/16”, and 1/2
spin-tite, end wrenches and / or sockets. Heavy duty models may require larger sizes.
1. Lay out the boom sections and assemble using the
DIMENSION sheet as a guide for position and hardware.
2. Cut a strip of masking tape about 6” long. Fold the
ends under and stick the tape to a flat surface, sticky
side up. Lay out the elements by length and position as
shown the DIMENSION sheet. NOTE: THE ELEMENTS
IN THIS ANTENNA DO NOT ALL TAPER IN LENGTH.
Now lift off the REFLECTOR and find the rough center by
balancing it across finger. Push on a black button insulator
to about 1/2” from center. Insert the element through the
holes at the rear of the boom and install the second
button. IF THE ELEMENT IS LOOSE IN THE BUTTONS,
SQUEEZE THE SMALL END OF EACH BUTTON
SLIGHTLY WITH PLIERS UNTIL IT OFFERS
SIGNIFICANT RESISTANCE WHEN THE ELEMENT IS
INSERTED. THIS WILL HELP TO HOLD THE ELEMENT
IN POSITION DURING SUBSEQUENT OPERATIONS.
Install the 3/16” rod DRIVEN ELEMENT as you did the
reflector. Then continue with the installation of the
DIRECTORS. Note that the Director Elements may not
consistently diminish in length from rear to front, so
pay close attention to length and position.
3. Now begin centering the elements. Use a tape measure to EQUALIZE the amount the element
sticking out on each side of the boom. Once all are centered, sight down the antenna from the rear
and compare tip symmetry. Look for any
obvious discrepancies and correct if found.
4. Stainless steel SHAFT RETAINERS are used
for securing the elements and insulators.
Always use retainers for permanent and long
term antenna installations. For most portable or
temporary use, the button insulators are
satisfactory and the retainers may be left off.
5. Use thumb and index finger to hold a Shaft
Retainer over end of the 3/8” X 3” push tube
(internal fingers dished into tube). Hold the
element firmly and start the keeper onto the rod
by applying pressure with the push tube. Push
the Shaft Retainer down element until tight against the button insulator (Locking pliers, lightly
clamped up against opposite button insulator will help maintain center reference and keep you from
pushing the first Shaft Retainer too far). Repeat for the opposite side. Continue installing Shaft
Retainers until all elements are locked in place.
6. Mount the DRIVEN ELEMENT FEED BLOCKS to the boom using a single 8-32 screw 1-1/4" long.
Orient with feed and balun connectors as shown on the Dimension Sheet. The ‘T’ block mounts
behind the rear driven element.
MASKINGTAPE
OREQUIVALENT
FACEUP
ELEMENTPREPARATION
REFLECTOR
ELEPREP
M.STAAL
5-24-05
FRONTDIRECTOR
418CP30 ASSEMBLY MANUAL

7. Generally the balun is installed in one long loop. Attach balun to the block connectors and tighten
gently using a 7/16" end wrench. Form the balun coax close to the boom and secure with cable ties
(snug but not crushing or kinking the coax).
8. Install the 8-32 x 1/4” set screws (internal Allen head - tool supplied) into the SHORTING BARS.
Slide the bars onto the 3/16” rod driven element tips and the 1/8" Feed Block Rods. Position the
Shorting Bars as specified on the DIMENSION SHEET: the distance given is between the outer
face of the Feed Block and the inner face of the Shorting Bar. Align the bars and rods with each
other and tighten the sets crews. NOTE: the shorting bar dimensions are different on the
OPTIONAL circular switched driven element.
9. Now attach all the cables. The two medium length cables are the 1/2 wave baluns. The long coax
cable goes to the front driven element. And the short cable goes to the rear driven element. Tighten
the connectors lightly with a 7/16” end wrench.
REMEMBER CENTER MOUNTED ANTENNA MUST BE PLACE ON A FIBERGLASS OR OTHER
STRONG, NON CONDUCTIVE MAST AND THE FEEDLINES MUST RUN OFF THE REAR OF
THE ANTENNA. THIS PREVENTS THE CIRCULAR FIELD OF THE ANTENNA FROM BEING
DISTORTED BY A METALLIC MAST OR METALLIC FEEDLINE.
10. For center mounted antennas, the boom to mast plate is normally mounted as close as possible to
the balance point (with feedline or a temporary equivalent attached). For rear mounted antennas,
use the boom length provided behind the reflector element. Keep mounting plate at least 1" from
any element. Secure plate with two U-bolts and the stainless nuts and lock washers provided. DO
NOT OVER TIGHTEN. Additional U-bolts and stainless nuts / lock washers are provided for
mounting the antenna to your mast. THIS COMPLETES THE ANTENNA ASSEMBLY.
11. For optimum performance, mount antenna high and in the clear. Always use high quality coax and
connectors. Old, corroded, or poor quality materials can SERIOUSLY affect VSWR, gain, and
pattern. If possible, test the antenna, connectors and feedline BEFORE installation. At 6' in height,
the antenna will exhibit performance approaching the specifications. If it doesn't, check feedline
and connectors for continuity and shorts. Check antenna shorting bars, element placement and
length, against Dimension Sheet.
12. MOUNTING AND STACKING INFORMATION
Rear mounted antennas can generally be mounted in any polarization to any type of mast,
conductive or non-conductive.
Center mounted antennas can also be mounted in any polarity. However, a mast or cross boom
in-line (parallel) with the element plane must be non-conductive. Anything conductive in the
element plane will disrupt the pattern and reduce performance (even the feedline). When a non-
conductive mast or cross boom is in-line with elements, route feedline away at right angles to the
elements and reattach at least 6" beyond element tips. Fiberglass is the recommended material for
a non-conductive mast or cross boom because of it's strength and weather resistance.
Stacking: See the Dimension Sheet for stacking separation dimensions.
1. All driven element blocks MUST be oriented to the same side of boom.
2. All boom-to-mast plates MUST be mounted at the same point on the boom.
3. Feed / phasing lines MUST be of equal electrical length or, ideally, multiples of 1 wavelength in
order to maintain equal phasing in the array.
418CP30 ASSEMBLY MANUAL

418CP30 DIMENSION SHEET
NOTE: RIGHT HAND CIRCULARITY SHOWN

418CP30 DRIVEN ELEMENT CABLE ROUTES
PHASING LINE
3/4 WAVE
JUNCTION BLOCK
SCREW, 8-32 X 1-1/4”
D.E. BLOCK
SCREW, 8-32 X 1-1/4”
D.E. BALUN
D.E. BALUN
PHASING LINE
1/4 WAVE
D.E. BLOCK
SCREW, 8-32 X 1-1/4”
FIG. 4
CABLE ROUTING DIAGRAM

DESCRIPTION ................................................................…………………………..QTY
BOOM SECTION #1, 1” X .058” X 48" SOE (M2ASB418CP30-1) ..........................1
BOOM SECTION #2, 1” X .058” X 60” SOE (M2ASB418CP30-2) ..........................1
BOOM SECTION #3, 1” X .058” X 26.5” (M2ASB418CP30-3)................................1
BOOM-TO-MAST PLATE, 3” X 4” X .125”(M2APT0019) ........................................1
ELEMENT SET , 3/16” X SEE DIMENSION SHEET ...............................................1
DRIVEN ELEMENT ASSEMBLY (SADEA418CP30)...............................................2
JUNCTION BLOCK ASSEMBLY (SADE0065) ........................................................1
BALUN CABLE , 1/2 WAVE RG-6U, 13” .................................................................2
PHASING LINE, LONG, 3/4 WAVE RG-6U, 6”........................................................1
PHASING LINE, SHORT, 1/4 WAVE RG-6U, 9” .....................................................1
U-BOLT AND CRADLE, 2".......................................................................................2
U-BOLT, 1-1/2".........................................................................................................2
U-BOLT 1” ................................................................................................................2
ASSEMBLY MANUAL ..............................................................................................1
IN HARDWARE BAG:
SHORTING BAR, 1/8” AND 3/16” HOLES..............................................................4
BUTTON INSULATORS...........................................................................................60
SHAFT RETAINER, (KEEPER) SS..........................................................................60
NUT, 5/16-18 SS ......................................................................................................4
LOCK WASHER, 5/16 SS ........................................................................................4
NUT, 1/4-20, SS .......................................................................................................4
LOCK WASHER, 1/4” SPLIT RING , SS..................................................................4
SCREW, 8-32 X 1-1/4” SS .......................................................................................7
SET SCREW, 8-32 X 1/4, SS...................................................................................8
LOCKNUT, 8-32 SS .................................................................................................4
CABLE TIE, NYLON ................................................................................................4
ALLEN HEAD WRENCH, 5/64”................................................................................1
PUSH TUBE, 3/8” X 3” .............................................................................................1
M2 ANTENNA SYSTEMS, INC.
4402 N. SELLAND AVE.
FRESNO, CA 93722
[phone] FAX: [phone]
www.m2inc.com Email: [email protected]
418CP30 PARTS & HARDWARE