Emco BICONILOG 3141 Скачать руководство пользователя

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0.5 dB), in vertically polarized measurements cable position can effect results, so it is

recommended that the cable be suspended horizontally back from the antenna at least 1

meter before any vertical drop. Below 150 MHz, bow-tie radiation dominates with a

dipole-like pattern, while above 150 MHz the radiation in the plane of the elements is

directional. The antenna has a mounting bracket and 1/4x20 UNC knob for attaching to

EMCO tripod and tower adaptors. Individual antenna factor calibration data is included

with each antenna. The Model 3141 can be used with or without the end frames of the T

bow-ties. However, calibration data is valid ONLY with the T bow-ties intact.

The unique feature of the Model 3141 is the T bow-tie elements. A T bow-tie

increases the equivalent dipole electrical length, thereby decreasing resonant frequency

and increasing efficiency in the 20-60 MHz range. Similarly, a regular bow-tie has a

lower resonant frequency than an equal length single-wire dipole. The T bow-tie has its

first resonance at a frequency where its length is about 0.22

, a regular bow-tie at a

length of 0.3

, and a tuned dipole at about a length of 0.48

. Thus at 50 MHz the 1.4 m

long T bow-tie of the Model 3141 behaves like a 2.8 m tuned dipole. Cross-polar

radiation is minimized because current flow on one of the T end frames is almost exactly

cancelled by the oppositely-phased current on the other T end.

Archived 3/18/10

Содержание BICONILOG 3141

Страница 1: ...USER MANUAL EMCO MODEL 3141 BICONILOGTM LOG PERIODIC T BOW TIE ANTENNA 399236 Rev A 01 97 Archived 3 18 10...

Страница 2: ...y transmit gain and receive antenna factor compared to a same length regular bow tie Although bow ties have been used for all elements on log periodic antennas in the past in EMC applications the adva...

Страница 3: ...er calibration data is valid ONLY with the T bow ties intact The unique feature of the Model 3141 is the T bow tie elements A T bow tie increases the equivalent dipole electrical length thereby decrea...

Страница 4: ...ropping vertically Both horizontal and vertical polarization is easily accomplished when the Model 3141 is mounted on a tower Vertical polarization on a tripod requires special consideration Since imm...

Страница 5: ...any other field strength not shown multiply the power in watts by the desired E field squared or P E E P V m V m 2 1 Actual transmitted field strength should be verified using an EMCO Model 7100 seri...

Страница 6: ...nd tip Figure 3 shows typical Model 3141 26 2000 MHz forward power required for 1 3 and 10 V m at 1 m from the tip of the antenna while Figure 4 is for 3 m from the antenna tip The power shown was mea...

Страница 7: ...7 10 100 1000 MHz 1 10 100 SWR Figure 1 EMCO Model 3141 typical SWR 10 100 1000 MHz 5 10 15 20 25 30 35 AF dB 1 m 1 m 3 m 10 m Figure 2 EMCO Model 3141 typical antenna factor Archived 3 18 10...

Страница 8: ...1 10 100 1000 W 1 V m 3 V m 10 V m 3 V m 80 AM Figure 3 EMCO Model 3141 typical 1 m forward power 20 30 40 50 60 70 80 MHz 0 1 1 10 100 1000 W 1 V m 3 V m 10 V m Figure 4 EMCO Model 3141 typical 3 m...

Страница 9: ...y range 26 2000 MHz Input impedance 50 VSWR 2 1 average CW power 1 kW above 60 MHz 500 W below 60 MHz Symmetry 0 5 dB Connector N female Mechanical Height T bow tie 75 cm Width T bow tie 136 cm Depth...

Страница 10: ...harged for our travel related costs This warranty does not apply to 1 Normal wear and tear of materials 2 Consumable items such as fuses batteries etc 3 Products which have been improperly installed m...