The JC Special...Mark II

... a limited-space antenna system for the 160 and 75 meter amateur bands requiring no tuning. This dipole antenna, approximately 162 feet in overall length, can be installed as an inverted vee, a sloper, a horizontal dipole, or a horizontal vee.

Center-fed with 52 ohm coax, this antenna is a full-sized half-wave dipole on the 75 meter band, having a bandwidth of 120 KHz, with VSWR less than 2:1. Bandwidth on 160 is 50 KHz.

The length for resonance on 75 meters is calculated by dividing the number 263 by the desired center frequency in megahertz. The frequency of resonance on the 160 meter band may be adjusted for your favorite portion of the band by trimming the extreme ends of the antenna, marked "X" below.

Close proximity to other antennas may affect resonance. Loading coils must be kept in the clear. An antenna tuner may be used if desired.

All components of this antenna system have been carefully selected for optimum electrical characteristics, physical strength, lightness, and resistance to corrosion. Eye-bolts and other fasteners are made of stainless steel.

This antenna can be used with maximum amateur legal power. A good grade of RG-8 or RG-58 coax cable is recommended. Use the heat-shrinkable tubing provided for weather-proofing your PL-259 coax plug.

After unpacking, attach the center insulator to a tree or building, then carefully uncoil each section. Pull hard to straighten. Since this wire has been annealed, it has a tendency to recoil. However, kinks must be avoided. The ends of this antenna must be suspended with non-conducting material such as polypropylene rope, as they contain HIGH R.F. VOLTAGES.

Approximate values for "X"
Freq. "X"
------------
1998 12' 0"
1970 12' 5"
1910 13' 5"
1850 14' 5"
1800 15' 3"

Approximate values for "Y"
Freq. "Y"
------------
3.950 66' 7"
3.900 67' 5"
3.850 68' 3"
3.800 69' 2"
3.750 70' 2"
3.700 71' 2"
3.650 72' 1"
3.600 73' 1"

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