M2 Antenna Systems 20M6-125 Manual - 20M6-125 Assembly Manual
NOTE: THE “DIMENSION SHEET” AND THE “HARDWARE ARRANGEMENT” DRAWINGS ARE
QUITE COMPLETE WITH ASSEMBLY INFORMATION. EXPERIENCED BUILDERS MAY NOT
REQUIRE THE WRITTEN INSTRUCTIONS. WHEN IN DOUBT, USE THE WRITTEN WORD. ANTI-
SEIZE PASTE (PENETROX OR NOALOX) IS RECOMMENDED ON ALL HARDWARE THREADS
AND ALUMINUM JOINTS. TOOLS REQUIRED: Electric drill, screw driver, 11/32" nut driver or
socket, 7/16" end wrench, 7/16", 1/2", and 9/16" socket set, measuring tape.
1. Pair up 1/2” element tip sections by length. Insert 1/2” sections into the swaged end of the 3/4” x
53” sections secure with 5/8” Compression Clamps (SEE COMPRESSION CLAMP & TIP ASSEMBLY
DETAIL). Set the proper exposed tip length (SEE DIMENSION SHEET). Install all tip sections. Use a
felt pen and masking tape to identify each element set by position as it is completed.
2. Slide a 7/8” X 23” EXTERNAL SLEEVE over the butt end of a 3/4" x 53” & 1/2” tip assembly and
align holes. Install this assembly into the end of a 1" x 48” element section with holes at 1/2” and 1-
1/2” from end. Use 8-32 x 1-1/4" screws and locknuts at the joint. Tighten securely. Slide a 7/8” x 32”
SLEEVE SECTION into the butt end of the 1” section and align holes. Attach a 1-1/4” x 48” ELEMENT
SECTION to 1” ELEMENT SECTION using 8-32 x 1-1/2” screws and locknuts. Repeat for all
elements.
3. PARASITIC ELEMENT ASSEMBLY: Slide a 1-1/2” x 30” INNER ELEMENT SECTION onto each
end of a 1-3/8” x 51” CENTER SLEEVE, align holes, and secure with a 1/4-20 x 2” bolt and locknut.
Slide on the second 1-1/2 x 30” section. Align the holes and secure with the second 1/4-20 x 2” bolt
and locknut. Place a clamp plate one either side at the center of this element assembly and rotate so
the bolt heads are up. Add the 1/4-20 x 2-3/4” bolts trough the 6 holes and add the locknuts. Check
the element centering again and then tighten the clamp block bolts evenly to keep the plates parallel.
Repeat for the other two PARASITIC ELEMENTS.
4. DRIVEN ELEMENT ASSEMBLY: Refer to the HARDWARE ARRANGEMENT drawing and
assemble THE LAST pair of ELEMENT CLAMP PLATES including the “L” BRACKET for mounting the
balun. Slide in the 1-1/4” x 24” fiberglass rod, center it, align holes up and down and tighten the clamp
bolts evenly. Now add the white poly rings to each side of the fiberglass rod and push them up against
the clamp plates. Insert the 1-/38” x 26” sleeves into the last two 1-1/2 x 30” SOE tubes. Align the
holes and carefully slide these assemblies over the fiberglass rod ends. Align all the holes and, FROM
THE BOTTOM, insert two 1/4-20 x 2-1/2” bolts. Drop on two HAIRPIN CLAMP BLOCKS and add a
locknut finger tight to each bolt.
5. BOOM ASSEMBLY: Inspect the CENTER BOOM SPLICE for any nicks or scratches. File smooth
if any found. Lightly oil or lubricate the COUPLING RINGS and insert the splice onto one plain end of
a 3” x 180” swaged boom section. Add the two 1/4-20 x 3-1/2 bolts and locknuts, but do not tighten.
Now slide the second boom section on and align the holes. Add the bolts and tighten. Next add the
3” x 180” plain ends. Add the 1/4-20 x 3-1/2 bolts and locknuts and tighten.
6. Orient the eyebolt eyes to the top of the boom. Place the boom on bucks or equivalent to get it to a
convenient working height. Position one PARASITIC CENTER SECTION one inch from the end of the
boom, add the saddle clamps and the four 1/4-20 x 3” bolts (a dab of Noalox on the threads make
insertion easy). Align the top of the clamp to the eyebolt and tighten the saddle clamps evenly. Next,
refer to the DIMENSION SHEET and using a tape measure and a marking pen or piece of tape, mark
the ELEMENT LOCATIONS on the boom. Mount the center element assemblies on the boom the
same as the reflector. Align each with the reflector and tighten.