ETS-Lindgren 3142C User Manual

Model 3142C

Archived 01/19/11

BiConiLog™ Antenna

User Manual

ETS-Lindgren L.P. reserves the right to make changes to any products herein to improve

Archived 01/19/11

functioning or design. Although the information in this document has been carefully reviewed and
is believed to be reliable, ETS-Lindgren does not assume any liability arising out of the
application or use of any product or circuit described herein; nor does it convey any license under
its patent rights nor the rights of others. All trademarks are the property of their respective
owners.

©Copyright 2000–2006 by ETS-Lindgren L.P. All Rights Reserved. No part of this
document may be copied by any means without written permission from
ETS-Lindgren L.P.

Trademarks used in this document: The ETS-Lindgren logo and BiConiLog are trademarks of

ETS-Lindgren L.P.

Revision Record | MANUAL MODEL 3142, Part # 399229, Rev. E

Revision Description Date

A Initial Release November, 2000

B Update to new format, add Model 3141

information

C Edit/update February, 2003

D Edit/update June, 2003

E Update bowtie/antenna knob information November, 2006

Internet Address

http://www.ETS-Lindgren.com

USA

1301 Arrow Point Drive
Cedar Park, TX 78613 USA
Tel: [phone]
Fax: [phone]
Email: [e-mail]

Japan

4-2-6, Kohinata
Bunkyo-ku, Tokyo 112-0006 Japan
Tel: [phone]
Fax: [phone]
Email: [e-mail]

Finland

Mekaanikontie 1, 27510
Eura, Finland
Tel: [phone]
Fax: [phone]
Email: [e-mail]

China

B507A Technology Fortune Center
No. 8 Xue Qing Road
Haidian District
Beijing Postcode: 100083 China
Tel: [phone]
Fax: [phone]
Email: [e-mail]

January, 2001

ii |

Table of Contents

Archived 01/19/11

Safety Symbol Definitions ................................................................................................................. v

General Safety Considerations ......................................................................................................... v

1.0 Introduction ................................................................................................................................ 7

2.0 Receiving Your Order ................................................................................................................ 9

2.1 Unpacking and Acceptance ................................................................................................... 9

2.2 Return Procedures ................................................................................................................. 9

3.0 Maintenance ............................................................................................................................ 11

4.0 Mounting Instructions .............................................................................................................. 13

4.1 Model 3142C Components .................................................................................................. 13

4.2 Mount the Bow-tie Elements ................................................................................................ 13

4.3 Connect the Optional End Plates to Create the T Bow-ties ................................................. 14

5.0 Application ............................................................................................................................... 17

5.1 Without Optional End Plates ................................................................................................ 17

5.2 With Optional End Plates ..................................................................................................... 18

6.0 Typical Data Without Optional End Plates .............................................................................. 19

6.1 Model 3142C Typical 26-3000 MHz VSWR ......................................................................... 19

6.2 Model 3142C Typical 26-3000 MHz Antenna Factor ........................................................... 19

6.3 Model 3142C Typical 26-3000 MHz Gain ............................................................................ 20

7.0 Typical Data with Optional End Plates .................................................................................... 21

7.1 Model 3142C Typical 26-3000 VSWR ................................................................................. 21

7.2 Model 3142C Typical 26-3000 MHz Antenna Factor ........................................................... 22

7.3 Model 3142C Typical 26-3000 MHz 1M Forward Power ..................................................... 23

7.4 Model 3142C Typical 26-3000 MHz 3M Forward Power ..................................................... 24

8.0 Specifications .......................................................................................................................... 25

8.1 Electrical Specifications ....................................................................................................... 25

8.2 Physical Specifications ........................................................................................................ 25

9.0 Warranty Policy for Standard EMCO Brand Products ............................................................. 27

9.1 Scope and Duration of Warranties ....................................................................................... 27

9.2 Warranty Exclusions ............................................................................................................ 27

9.3 Buyer’s Remedies ................................................................................................................ 28

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iv |

Safety Symbol Definitions

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This product and related documentation must be reviewed for familiarization with
safety markings and instructions prior to operation of the product.

Safety Symbol Definition

REFER TO MANUAL—When the product is marked with this symbol

refer to the instruction manual for additional information. If the

!

OR

instruction manual has been misplaced, go to www.ets-lindgren.com
downloadable files or contact ETS-Lindgren customer service.

General Safety Considerations

Safety Symbol Definition

BEFORE SERVICING: CONTACT ETS-LINDGREN
(+1.512.531.6400)—Servicing or modifying the unit without

WARRAN TY

ETS-Lindgren authorization may void your warranty. If an attempt to
service the unit must be made, disconnect all electrical power prior to
beginning. Voltages exist at many points within the instrument that
could, if contacted, cause personal injury. Only trained service
personnel should perform adjustments and/or service procedures upon

this instrument. Capacitors inside this instrument may still be charged

even when the instrument is disconnected from the power source.

for

ONLY QUALIFIED PERSONNEL should operate or service this

equipment.

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1.0 Introduction

The ETS-Lindgren Model 3142C BiConiLog™ Antenna is designed as a dual­purpose antenna that can be used for both emissions and immunity applications.
The Model 3142C is a hybrid linearly polarized EMC antenna consisting of a
log-periodic dipole array (LPDA) and a single bow-tie antenna. Historically,
bow-ties have been used for all elements on log-periodic antennas, and in EMC
applications the advantage is an extension of the useful low frequency range of
the typical LPDAs from 100 MHz to 30 MHz. At 30 MHz, an efficient single dipole
type antenna must be five meters long, but a suitable performance is obtained
with a bow-tie that is 1.7-meter long.

A simple wire outline bow-tie antenna is narrowband compared to a sheet
bow-tie or biconical, so struts are added to the Model 3142C bow-ties to better
simulate the broadband sheet bow-tie. The standard self-balun feed of the
log-periodic also provides a matched, balanced feed to the bow-tie elements.
Below 150 MHz, bow-tie radiation dominates with a dipole-like pattern, and
above 150 MHz the radiation in the plane of the elements is directional.

To prevent cable pickup below 100 MHz, the Model 3142C contains a balun that
acts as a common-mode choke to keep unbalanced current off the coaxial feed
cable outer shield. Though the Model 3142C is highly balanced, 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 one
meter before any vertical drop.

The antenna has a mounting bracket and ¼-20 UNC thread knob to attach to an
ETS-Lindgren tripod or tower adapter. Individual antenna factors and gain
calibration data is included with each antenna.

The Model 3142C optional end plates (part #106572) are available to improve
gain for immunity testing. This option consists of two end plates that are easily
attached and detached by hand using captive screw knobs. When the end plates
are attached it creates a T-shaped bow-tie element.

For any dipole-type antenna to transmit or receive energy most efficiently, its
length must be nearly a half wavelength, which is about 4.6 meters long at
30 MHz, and 2.8 meters long at 50 MHz. Unfortunately, this is too unwieldy for
many anechoic chambers and test sites. The optional end plates of the Model
3142C make it appear like an antenna twice as long as its 1.4 meter length. The
result is approximately a 10 dB improvement in low frequency transmit gain and
receive antenna factor compared to a same length regular bow-tie.

Introduction | 7

Archived 01/19/11

With the end plates attached to the Model 3142C bow-tie elements, the
equivalent dipole electrical length is increased, which decreases resonant
frequency and increases efficiency in the 20 to 60 MHz range. Similarly, the
regular bow-tie has a lower resonant frequency than an equal length single-wire
dipole. The T end plate option has its first resonance at a frequency where its
length is about 0.22 λ, a regular bow-tie at a length of 0.3 λ, and a tuned dipole at
about a length of 0.48 λ. Thus, at 50 MHz the 1.4-meter long end plate option
behaves as if a 2.8 meter tuned dipole. Cross-polar radiation is minimized
because current flow on one of the T end frames is almost completely cancelled
by the opposite-phased current on the other T end.

8 | Introduction

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2.0 Receiving Your Order

2.1 Unpacking and Acceptance

Step 1. Upon delivery of your order, inspect the shipping container(s) for

evidence of damage. Record any damage on the delivery receipt before signing
it. In case of concealed damage or loss, retain the packing materials for
inspection by the carrier.

Step 2. Remove the product from its shipping container(s). Save the container(s)

and any protective packing materials for future use.

Step 3. Check all materials against the packing list to verify that the equipment

you received matches what was ordered. If you find any discrepancies, note
them and call ETS-Lindgren Customer Service for further instructions.

Ensure that you are satisfied with the contents and condition of your order prior
to placing the product into service.

2.2 Return Procedures

To return a system or system component:

Step 1. Contact ETS-Lindgren Customer Service to obtain an SRO, Service

Request Order.

Step 2. Briefly describe the problem in writing. Give details regarding the

observed symptom(s) or error codes, and whether the problem is constant or
intermittent in nature. Please include the date(s), the service representative you
spoke with, and the nature of the conversation. Include the serial number of the
item being returned.

Step 3. Package the system or component carefully. If possible, use the original

packing materials to return a system or system component to ETS-Lindgren at
the following address:

ETS-Lindgren

Attn. Service Department

301 Arrow Point Drive

Cedar Park, TX, USA 78613

Phone: [phone]

Receiving Your Order | 9