M2 Antenna Systems 248CP22A User Manual

M2 Antenna Systems, Inc.

Model No: 248CP22A

SPECIFICATIONS:

Model ......................................... 248CP22A

Frequency Range ....................... 235 To 260 mHz

*Gain .......................................... 13.8 dBi

Front to back .............................. 20 dB Typical

Beamwidth ............................... E=36° H=40°

Feed type ................................... “T” Match

Feed Impedance. ....................... 50 Ohms Unbalanced

Maximum VSWR ........................ 1.5:1 Typical

Input Connector .......................... “N” Female

*Subtract 2.14 from dBi for dBd

Power Handling .......................... 1 kW

Boom Length / Dia ...................... 139-1/2” / 1”

Maximum Element Length .......... 25”

Turning Radius: .......................... 84”

Stacking Distance ....................... 68” High & 71” Wide

Mast Size .................................... 1-1/2” to 2” Nom.

Wind area / Survival ................... 0.93 Sq. Ft. / 100 MPH

Weight / Ship Wt. ........................ 5 Lbs. / 8 Lbs.

FEATURES:

The 248CP22A is high 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 work but is also excellent for terrestrial uses like ATV, repeater operation, and long haul tropo DX.
The CNC machined driven element module is O-ring sealed and weather tight for low maintenance and long-term
peak performance. Internal connections 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 for the boom length: that’s the M

2

248CP22A!

M2 Antenna Systems, Inc. 4402 N. Selland Ave. Fresno, CA 93722

Tel: [phone] Fax: [phone] Web: www.m2inc.com

©2015 M2 Antenna Systems Incorporated

9/15/15
Rev.00

248CP22A DIMENSION SHEET

248CP22A ASSEMBLY MANUAL

TOOL REQUIRED FOR ASSEMBLY: screwdriver, 11/32 nut driver or wrench, 7/16” and 1/2” socket or end

wrenches, measuring tape.

1. Assemble the boom using 8-32 X 1-1/4 screws and locknuts to join sections. (SEE DIMENSION SHEET).

ASSEMBLING THE HORIZONTAL ELEMENTS

2. Lay out the elements by “Horizontal” length and position as shown the DIMENSION SHEET. Start with the
reflector (longest) element. Balance it on your finger to find rough center and push on a black button
insulator to about 1/2” off center. Push the element through the holes 1.937” from the rear of the boom and
install the second button, snugging it up into boom. DO NOT BOTHER CENTERING the element at this time
and DO NOT INSTALL the stainless steel shaft retainers yet. It is easier to do it after all the horizontal
elements are installed in the boom.

3. Install the 3/16” rod DRIVEN ELEMENT as you did the reflector. Then continue with the installation of the
DIRECTORS. Note : the D irector E leme nts do not consistently diminish in le ngth from rea r to front, so pa y

close attention to length and position.

4. Now begin centering the elements. Use a tape measure to EQUALIZE the amount the element sticking out
on each side of the boom. 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.

5. Stainless steel SHAFT RETAINERS lock the
elements in place. They should always be
used for permanent and long term antenna
installations. For portable or temporary use,
the button insulators are adequate for holding
the elements and the retainers may be left
off. To install the stainless steel SHAFT
RETAINERS, use thumb and forefinger to
hold the retainer over the end of the PUSH
TUBE ( 3/8" x 3" tube, supplied in the kit),
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 retainer completely off the
element, and start over). Install another retainer to the opposite side of the element. Continue installing
retainers until all elements are secured.

6. Mount the HORIZONTAL P.S. DRIVEN ELEMENT ASSEMBLY to the TOP of the boom using a single

8-32 X 1-1/4" screw (SEE PICTURE).

7. Install the 8-32 x 1/4” set screws (internal Allen head - tool supplied) into the SHORTING BARS. Slide the
bars onto the 1/4" Driven Element Block Rods and the 3/16" driven element rod. Position the S horting Bars
as shown on dimension sheet.