Shively Labs FM Antennas and Accessories
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Typical Data for
Model 6600 FM Antenna (half-wave-spaced)

  • Horizontal Polarization
  • Power Rating: 5 kW per Bay
  • Shively Standard Features:
    • Ring Stub Design
    • Low Weight and Windload
    • Consistently Predictable Patterns
    • Digital-Ready
    • Pattern Studies Available
    • No Factory Personnel Needed to Install
    • Adjustable Fine-Matching Transformer
    • Radomes and Deicers Available
    • Rugged Corrosion-Resistant Mounts
    • Works with Regular Towers; No Need for Special Frequency-Sensitive Tower Sections
    • Pressure Relief Valve for Easy Purging of the System
    • Special Spacing, Null Fill and Beam Tilt Available

Performance Specifications:

Polarization:
Horizontal only.
VSWR:
1.08 : 1 ± 100 kHz.
1.14 : 1 ± 200 kHz
Azimuth Pattern Circularity:
± 1.5 dB on pole.
Input Connection:
Female 3-1/8" EIA.

Electrical Specifications (half-wave-spaced):


No. of
Bays
Gain

Power
Rating
kW
No. of
Bays
Gain

Power
Rating
kW
Power dB Power dB


2
1.40
1.46
10
8
5.06
7.03
40
3
2.02
4.05
15
10
6.28
7.96
40
4
2.62
4.17
20
12
7.50
8.74
40
5
3.24
5.08
25
14
8.70
9.39
40
6
3.84
5.83
30
16
9.92
9.96
40

Notes:

Our gain figures are derived from the computed directivity and include the losses in the antenna feed system. Gain is computed for 98 MHz and will vary across the band.

Gain is provided for horizontal polarization only. Gain will be reduced if null fill, beam tilt, or special wavelength spacing is provided. Gain will increase in a directional array by the directivity of the azimuth pattern.

Size and Weight (half-wave-spaced):


No. of Bays Vertical Tower Space

Weight

Antenna radiation aperture

Physical
space used

Total tower space recommended

without
radomes

with
radomes

with radomes &
1/2"radial ice

ft m ft m ft m lb N lb N lb N

2
5
1.6
14
4.6
25
8.2
87
388
153
682
318
1418
3
10
3.3
19
6.2
30
9.8
127
566
226
1008
484
2159
4
15
4.9
24
7.9
35
11.5
168
749
300
1338
650
2899
5
20
6.6
29
9.5
40
13.1
208
928
373
1664
816
3639
6
25
8.2
34
11.2
45
14.8
249
1111
447
1994
982
4380
7
30
9.8
39
12.8
50
16.4
289
1289
520
2319
1148
5120
8
35
11.5
38
12.5
55
18.0
308
1374
572
2551
1271
5669
10
45
14.8
48
15.7
65
21.3
375
1673
705
3144
1578
7038
12
55
18.0
58
19.0
75
24.6
456
2034
852
3800
1910
8519
14
65
21.3
68
22.3
85
27.9
537
2395
999
4456
2242
9999
16
75
24.6
78
25.6
95
31.2
619
2761
1147
5116
2575
11485

Windload (full-wave-spaced):


No. of
Bays
Revision "C"

Revision "F"

without radomes

with radomes

with radomes & 1/2" radial ice

without radomes

with radomes

with radomes & 1/2" radial ice

lb N lb N lb N ft² ft² ft²

2
97
433
254
1133
316
1409
3.6
0.3
7.6
0.7
9.4
0.9
3
167
745
402
1793
501
2234
6.0
0.6
12.0
1.1
15.1
1.4
4
237
1057
550
2453
686
3060
8.5
0.8
16.4
1.5
20.7
1.9
5
307
1369
698
3113
871
3885
10.9
1.0
20.8
1.9
26.4
2.5
6
377
1681
846
3773
1056
4710
13.3
1.2
25.2
2.3
32.0
3.0
7
447
1994
994
4433
1241
5535
15.8
1.5
29.6
2.7
37.7
3.5
8
490
2185
1116
4977
1380
6155
17.3
1.6
33.1
3.1
41.8
3.9
10
587
2618
1369
6106
1693
7551
21.0
2.0
40.9
3.8
51.7
4.8
12
726
3238
1665
7426
2063
9201
25.9
2.4
49.7
4.6
63.0
5.9
14
866
3862
1961
8746
2434
10856
30.8
2.9
58.5
5.4
74.3
6.9
16
1006
4487
2257
10066
2803
12501
35.6
3.3
67.4
6.3
85.7
8.0

Notes:

  1. The mounting structure must not flex more than ± 1/2 in (± 1.2 cm) in any 10-ft (3-meter) section. Five feet (1.5 m) of mounting structure is required above and below the antenna bays for proper pattern formation.
  2. Antenna radiation aperture is the distance from the center of the top bay to the center of the bottom bay. Physical space used is from the top of the top bay to the input flange at the bottom of the array, or the bottom of the bottom bay in a center-fed array. Total tower space recommended allows ten feet (3 m) of clear tower space above and below the antenna to protect from pattern interference by other antennas. At frequencies lower than 98 MHz, each of these dimensions will increase by up to 1 ft (0.3 m) per bay.
  3. Seven bays or less are normally end-fed. All antennas supplied with beam tilt will be center-fed. Antennas with an odd number of bays are normally not available with center feed.
  4. Windload and weight tabulations are estimates and assume 98 MHz. They include the bay, interbay feedline, input connection, and a fine-matching transformer. No values have been included in these tabulations for mounts. Actual values vary with the specific installation. Contact us with details of your installation if more precise values are needed.
  5. Antenna windloads are calculated for 112 mph (180 kph), using 50 psf (2400 N/m²) for flats and 33 psf (1600 N/m²) for rounds] per EIA standard RS-222-C and CSA standard S37-94. The surface area is calculated per EIA standard RS-222-F (CaAc).
  6. Ask for technical assistance at Shively if you are planning to mount antennas on AM towers or install them at altitudes over 3,000 ft (915 m) above mean sea level.

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Last updated: 11/30/2007
Webmaster: Al Friend
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