WADE Antenna, Inc. J-283X User manual

INSTRUCTION BOOKLET
J-283X
RUGGEDIZED VHF-UHF-FM
J-SERIES ANTENNA
BY
Please Note: A qualified structural engineer should be
consulted prior to mounting an antenna
on a tower or support structure.
www.wadeantenna.com
30332-001 Rev. J

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6-ANTENNA MOUNTING
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Assemble the mast clamp plate and U-bolts to the insulated crossarm separator
as shown in Figure 4. U-bolts will accommodate masts up to 2” in diameter.
Slip the U-bolts over the mast, orient antenna towards desired stations and
tighten U-bolts securely.
7-CABLE ROUTING
Connect cable at rear of bottom crossarm. Bring cable back to the mast at an
angle so that it is kept away from the crossarm. Leave enough slack to
remove strain from the cable and secure to the mast.
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1-GENERAL DESCRIPTION
The TACO Model J-283X VHF-UHF-FM antenna is of rugged design and
will operate through the CH2 to CH83 television channels
(55-108 MHz and 470-890 MHz). It is of the log periodic design principle and
exhibits medium gain across the frequency band.
2-THEORY OF OPERATION
The antenna is comprised of 8 VHF and 7 UHF elements connected to a
parallel pair of 1¼” aluminum crossarms that form the antenna transmission
line. To accomplish end fire log periodic operation, the elements are tapered
from the front of the antenna to the back and successive dipole halves are
transposed along the antenna transmission line. An internal cable must be fed
through the lower aluminum crossarm which functions as a balun which
converts the balanced 75 ohms input at the front of the antenna to a 75 ohm
unbalanced coaxial “F” fitting. This internal “balun” effectively chokes off
the surface currents normally associated with a balanced feed and eliminates
line radiation.
3-ELECTRICAL CHARACTERISTICS (TYPICAL)
FIGURE 4
(Mast Clamp and U-Bolt Assembly)

4-SPECIFICATIONS
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ELECTRICAL 
GAIN (dBic)* See Gain Curves
IMPEDANCE 75 ohm, 1.5:1 VSWR
FRONT-TO-BACK RATIO VHF: 18 dB; UHF: 20 dB
BEAMWIDTH (degrees) VHF: (Lo) 70°, (Hi) 45°; UHF: 55°
ELEMENTS 8 VHF, 7 UHF
TERMINAL: Type “F”
TERMINAL: Impedance 75-ohms
MECHANICAL
BOOM LENGTH 90.50 in. (229.87 cm)
WEIGHT 20 lbs (9.09 kg)
MOUNT (Mast diameter) 1.5 in. (3.81 cm`) to 2.5 in.
(6.35 cm)
WINDLOAD
85 mph
100 mph
Thrust
No Ice ¼” Ice
90 lbs 152 lbs
122 lbs 208 lbs
FIGURE 3
(UHF Driver Section Assembly)

5-ASSEMBLY
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Machine screws and hex nuts are provided for bolting on the double sections
of the “X” elements and the shorter straight elements. Lock washers should
be used with a spintite or wrench. Do not over tighten. Over tightening to the
point of element or crossarm distortion will weaken the antenna assembly.
 1. Assemble the two halves of the square reflector to the rear of the
crossarm. (Marked “1”) (See Figure 1)
2. Assemble the longest “X” element thirteen inches ahead of the
square reflector. Arrows on the crossarm indicate the polarity of
the long portion of the elements. (Marked “2”) (See Figure 1 &
Figure 2)
3. Assemble the remaining “X” elements using progressively shorter
elements towards the front of the antenna. Be sure to observe
element polarity as indicated by the arrows. Element halves with
stub extensions should be mounted on outside of crossarms.
(Marked “3” through “9”) (See Figure 1)
4. Use screws to assemble the two 14” UHF reflectors six inches in
front of the forward “X” element. (Marked “11”) (See Figure 1)
5. Assemble the two straight 36-1/2” VHF elements five inches ahead of
the UHF reflectors. Arrows indicate polarity of long portion of the
element. (Marked “12”) (See figure 1)
6. Connect the four UHF driver sections to the matching holes on the
crossarms. The sections with threaded nit inserts mount on the
inner sides of the crossarms. Shortest elements face towards the
front. Inner and outer sections on each crossarm should match with
inner and outer elements forming half of the “X” elements.
(Marked “13” & “14”) (See figure 3)
FIGURE 1
(Element Assembly Detail)
FIGURE 2
(Typical “X” Element Assembly)
Position 5
Position 5
Position 6
Position 6