Telex ALP-450 User Manual 2

8601 East Cornhusker Highway, P.O. Box 5579, Lincoln NE 68505

INSTRUCTION MANUAL

General Description

UHF Log Periodic Antenna

Order No. 71147000 PN802573

The ALP-450 is a broadband directional log peri­odic antenna. It will receive any frequency from
450 to 900 MHz. The “gain” of this antenna en­ables it to receive signals from a greater distance
than a typical “whip” type antenna.

SPECIFICATIONS

(average)

Gain ..................................................................................................................4.6 dBd

1/2 Power Beam Width .........................................................................................120°

Front-to-Back Ratio...........................................................................................19.4 dB

SWR.......................................................................................................................1.5:1

Input Impedance ................................................................................................50 ohm

Input Connector ....................................................................................................TNC

Antenna Placement

The ALP-450 should be placed in a position that
has a clear view of the transmitter(s) for best re­sults. Obstructions such as walls, ceilings, and
metal objects will reduce range and performance.

Log Periodic Antennas are also directional (like a
TV antenna) and will have the best reception when
pointed at the transmitter. This yields the benefit of
less interference from unwanted signals coming
from the back or side of the antenna.

Antenna Mounting

The ALP-450 is supplied with a variety of mount­ing hardware. It should always be mounted verti­cally with the arrows pointing toward the
transmitter(s). See Figure 1.

Figure 1

Antenna Mounting

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Microphone Stand Adaptor

Attach the microphone stand adaptor using the
screws and spacers supplied with it. See Figure 2.

Figure 2

Microphone Stand Adaptor

Angle Bracket

Attach the angle bracket using the nuts,
lockwashers, and screws supplied with it. Self tap­ping screws are supplied for securing the bracket to
wood, metal, or other surfaces. See Figure 3.

Figure 3

Angle Bracket

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Clamps

Clamps are provided for mounting the ALP-450 on
pipes, scaffolds, tree limbs, etc.. Attach the clamps
with the hardware supplied. See Figure 4.

Figure 4

Clamps

Do not clamp the antenna to horizontal metal
objects that extend past the clamp. See Figure 5.
This will detune the antenna and cause loss of
range and performance.

GOOD

Figure 5

BAD

Clamp Mounting

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Coax Cable

For best results, itis recommended that cable losses
be kept under 4 dB. (Every 3 dB of signal loss re­sults in a system operating distance reduction of
25%).

MOUNTING SUGGESTIONS

See the accessories section of this manual for spe­cial low loss cable assemblies.

Mic Boom

Mic Stand

Wall

Top Surface

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Pipe or Scaffold

Tree Limb

Combination:

Bracket with Clamps

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Special Low Loss Antenna Cables with
TNC Connects

Length Part No.

10 Ft. (3 meters) 690419

25 Ft. (7.6 meters) 71151-025

50 Ft. (15 meters) 71151-050
75 Ft. (23 meters) 71151-075

100 Ft. (30 meters) 71151-100

ACCESSORIES

PRINTED IN U.S.A.
Copyright© 1995 by Telex
TELEX COMMUNICATIONS, INC.
All rights reserved.
20 Sept 1995

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