LOG PERIODIC ANTENNAS

Seavey Engineering has developed specialty log-periodic antennas for use in the VHF through C-band frequency ranges. Both pyramidal and crossed structures are available. Several high power designs have been delivered.

All models are dual polarized with a minimum of 20 dB isolation and a maximum 2:1 VSWR. All models are available with a compatible quadrature hybrid for dual circular polarized operation. Those products designated with a Feed Option can be used as feeds for reflectors with F/D ratios in the 0.40 - 0.55 range.

The following are some typical designs:

pg55a
Model 9162-800-6
140 - 650 MHz
pg55b
Model 9783-800
200 - 500 MHz
SPECIFICATIONS
Model
Number		 Frequency
MHz		 Polarization Dimension
W		 Dimension
D		 Dimension
L		 RF
Port		 Power Handling
Watts, CW		 Feed
Option
9162-800-6
140 - 150
Dual Linear (*)
38
38
42
N
100
Yes
9783-800
200 - 500
Dual Linear (*)
38
38
42
N
1500
Yes
9783-820
500 - 2000
Dual Linear (*)
16
16
18
N
1000
Yes
9783-820
600 - 4000
Dual Linear (*)
13
13
13
TNC
50
YES
9421-850
790 - 1000
RHCP
5
5
8
TNC
50
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(*) Dual Circular with added quadrature hybrid option.

Model 9421-850 is a crossed LP design with a single feed point. It has an axial ratio less than 3 dB from 790 - 1000 MHz and is useful as an array element.

pg55c
Model 9783-810
500 - 2000 MHz
pg55d
Model 9421-850
790 - 1000 MHz