BUTTONHOOK

Standard "buttonhook"-style feeds are available for a wide range of line-of-sight microwave antennas. Feeds consist of a high efficiency scalar feedhorn. An ortho-mode transducer (OMT) is included when dual polarization is required. Formed rectangular waveguide(s) support the feed system and route signals to the rear of the parabolic reflector.

All Seavey Engineering line-of-sight feeds are designed to meet the stringent gain and sidelobe envelope requirements of FCC Parts 21 and 94 for Standards A or B as specified. Our feeds have also been qualified for compliance with Canadian DOC and British DTI specifications. Extensive sets of test data are available showing Radiation Pattern Envelopes of complete antennas with these feed systems.In general, line-of-sight feed mounting is customized to a particular reflector. Modification of any of the standard mounting designs can be done to your specifications. Standard mounting provides for full polarization rotation capability from the rear of the reflector. All feeds are rated for 2 psig internal pressure.To order a particular feed, specify Seavey Engineering part number "FL" followed by the reflector size in inches and the Frequency Designation listed below. Add a "D" for dual polarized operation.For example: a feed for a 30 inch reflector with a standard 10 inch focal length operating with dual polarization in 21.2 - 23.6 GHz band is FL30-212D.
pg102a
SPECIFICATIONS
Standard Frequency
Band, GHz		 Frequency
Designation		 Waveguide
Port
10.5 - 10.7
-105
WR-90
10.7 - 11.7
-107
WR-75
12.5 - 15.5
-125
WR-62
14.4 - 15.35
-144
WR-62
16.9 - 17.2
-169
WR-62
17.7 - 19.7
-177
WR-42
17.7 - 23.6
-177B
WR-42
21.2 - 23.6
-212
WR-42
27.5 - 29.5
-275
WR-28
37.0 - 39.5
-370
WR-28
Feeds are provided for reflector diameters ranging from
12 inches to 120 inches. The following are standard reflector diameters
and corresponding focal lengths.

OPTIONS:
  • Pressurization to 10 psig

  • Additional suport struts on larger reflectors

  • Dual polarization (two ports)

  • Special Focal Lengths
STANDARD FOCAL LENGTHS
Reflector Diameter
Inches		 Focal Length
Inches
12
4
18
6
24
8
27
9
30
10
48
16
72
24
96
32
120
40