Advertisement
2M HO LOOP ASSEMBLY MANUAL
1.Insert the 1/4-20 x 1/4" set screws a few threads into the two connector blocks. Use the 1/8" Allen
wrench provided. Insert the 1/4-20 x 1/4" set screws a few threads into the ends of the shorting bar.
2. Refer to the HO-LOOP ASSEMBLY SHEET and insert the tubes into the two connector blocks as
shown. Slide on the shorting bar, align the loops and GENTLY tighten the 1/4-20 x 1/4" set screw onto
the tubes. Slight bending of the tubes will ensure that all tubes are straight and square to each other.
Be sure the blocks are set to the starting 'A' dimension. The 'A' dimensions controls the FREQUENCY.
3. Set the shorting bar to the 'B' dimension shown and tighten gently. When complete check match and
tighten . The 'B' dimension controls the MATCH
4. Once the loop is assembled either final tune it in its final position on your vehicle or if tower mounted,
simulate the mast size and other conditions to minimize final tuning in position.
4. That is about it. A 3/8-24 x 1" bolt and washer is provided to attach the HO LOOP to any standard
mobile mast or any M2 mast available as an option.
REMEMBER, HORIZONTALLY POLARIZED ANTENNAS ARE AFFECTED BY THE GROUND SO
THE HIGHER YOU AND GET YOUR HOOP LOOP THE BETTER. The ground can be your friend as
well providing as much as 6 dB additional ground gain at some angle above the horizon. That angle is
defined by the frequency and height above ground. At one wavelength, 80" at two meters, the typical
angle of maximum radiation will be about 14 degrees. At two wavelengths, the angle is 7 degrees and
at 4 wavelengths ( 27 ft.), the angle is 3.5 degrees. Net gain improves with height because the pattern
hits the ground at a more grazing angle giving up less energy to the ground.
In most mobile installations 10 to 11 feet is about the practical limit for most driving conditions. The HO
LOOP works at just 18" above a vehicle roof and contacts out 200 miles are quite common. However
you will find more people to talk to and longer if you can get the HO LOOP up at the 10 foot level.
POWER CONSIDERATIONS : 10 Watts into the HO LOOP will do well out to about 80 miles. 150
Watts gets you into that 200 mile category and 350 to 400 Watts get to the 300-400 and you will enjoy
much longer QSO's on a regular basis. From a hill top location 600-800 mile QSO's have been reported
several times. We hope you enjoy your new HO LOOP and please keep an ear out for those rare but
wonderful skip openings to other parts of the country!
Contact M2 for optional items available for your HO LOOP!
2
M
ANTENNA SYSTEMS, INC.
4402 N. Selland Ave.
Fresno, CA 93722
(559) 432-8873 Fax: 432-3059
www.m2inc.com
Email:
sales@m2inc.com
Advertisement
