Lectrosonics ALP650H Specifications

ALP Series

TECHNICAL DATA

LPDA Antennas

ALP500 ALP620 ALP650 Series

Economical design ideal for

fixed applications

Skeletal design for decreased

wind loading

Onboard amplifier ideal for

long cable runs, phantom

powered from Venue,

UMC16 or Bias T

The ALP Series antennas are a Log Periodic Dipole

Array (LPDA) design that provides a useful directional
pattern over a broad frequency bandwidth. Many “gain
antennas” (those designs with a directional pattern) are

limited in bandwidth, making them awkward for use in

multi-channel wireless systems and with frequency agile
wireless systems. With VSWR below 2:1 from 450 to 862
MHz, the broad bandwidth of the ALP Series covers a

broad section of the band used for Lectrosonics wireless

microphone and IFB systems, yet still provides the direc­tional pattern needed to cover long distances.

All ALP Series antennas are constructed of 1/8” FR4
fiberglass circuit board material and are extremely rug­ged. The ALP620 and ALP650 Series antennas include
a protective cover over the BNC connector, making them
suited for field production, while the more economi­cal ALP500 is better suited for indoor installation. The
perforated body of the ALP620 makes it resistant to wind
loading outdoors. The ALP650 models are “receive only”
models, featuring a built-in amplier with adjustable gain
for use with long coaxial cable runs and/or RF splitters.

The antennas can be mounted horizontally or vertically
by removing four screws and repositioning the mount-

ing block. This helps to position the antenna away from

nearby reective surfaces to preserve more of the natu-

ral pattern of the LPDA design.

Versatile Mounting Block

The mounting block on all ALP Series antennas can
accept three common sizes of threads:

• 1/4”-20 (tripod

mount)

• 3/8”-16 (pro

tripod mount)

• 5/8”-27 (mic

stand)

A 3/8”-16 stud (Part
#28769) is included

with all ALP Series
antennas.

The mounting
block can be
rotated to allow
horizontal
or vertical
mounting

Rio Rancho, NM, USA
www.lectrosonics.com

ALP650

Powering the ALP650

DC power is supplied to the

amplifier through the connected

coaxial cable from a BIAS T,

UMC16B or VENUE receiver.

DC POWER TO ALP650

RF OUT

ALP650

The BIAS T connects external

DC power to the antenna, blocks

the DC from its output to pre-

vent it from entering the receiver

antenna ports and passes the

RF output of the antenna to the

receiver.

9 to 16 VDC

RF OUT

BIAS T

ANT AANT B

Antenna Power Jumpers

VENUE RECEIVER

The VENUE receiver also includes

a DC power pass-through to operate

the ALP650 antenna amplier. Jump-

ers on the circuit board enable and

disable the DC power.

NOTE: The three examples shown above are
mutually exclusive. Only one of them should be

used in each installation.

OR

BIAS T

RF OUT

9 to 16 VDC

ANT A

Antenna Power Jumpers

ANT B

UMC16B MULTICOUPLER

The UMC16B multicoupler passes DC

power from its supply to the antenna

input ports to power the ALP650

through the coaxial cable. Jumpers on

the circuit board enable or disable the

DC power.

Active jumper

Adjusting Gain on the ALP650 Amplifier

In cases where the antenna is feeding a long coaxial

cable run and/or a splitter, additional gain is generally

needed. The goal is to compensate for the loss through

the cabling and deliver a signal level equivalent to con­necting the antenna directly to the receiver. Too much
gain adds unnecessary noise and some risk of increas­ing IM (intermodulation) in the receiver. Too little gain

runs the risk of dropouts in the reception.

Three jumpers are provided to adjust the gain from the
built-in amplier:

Jumper Value Attenuation Resulting Gain

0 0 dB 12 dB

-4 4 dB 8 dB

-7 7 dB 5 dB

Add up the loss caused by long coaxial cable runs,
antenna splitters, etc. and set the gain as closely as

possible to the total loss. For example, consider a 4-way
passive splitter such as the ZFSC41 with 6 db of loss
at each output and a coaxial cable such as the ARG15
with 2 db of loss, for a total loss of 8 dB. In this case,
the amplier should be used with the 4 dB attenuator to
produce the needed 8 dB of gain (12 - 4 = 8). One of the
jumpers must be in the active position at all times.

Store other jumpers here

Optional Mounting Adapter Kit

Threaded adapter

for standard lighting
clamps. 1/2” diameter
x 6 inch long. 3/8”-16

thread - both ends.

(PART # 26311-1)

Threaded adapter for

photo/video tripod

mounting. 1/2” diameter

x 1 3/4” long. 3/8”-16

thread on one end, 1/4”-

20 on the other.

(PART # 26312-1)

Microphone stand adapter, 1

1/2” long. 5/8”- 27 thread on one

end, with 3/8”-16 thread in other

1/4” - 20 threaded adapter

(PART # 28770)

(part # ALPKIT)

end. Knurled finish.

(PART # 26313-1)

Optional Accessories

Mini-Circuits passive splitters: Loss:

ZSC24 (2-way) 3.4 dB

ZSC41 (4-way) 6.8 dB

ZSC843 (8-way) 10.2 dB

Coaxial Cables: Loss:

ARG2 (2 ft. RG-8/X - Belden 9258) .25 dB

ARG2RT (2 ft. RG174/U - Belden 8216) .50 dB
(right angle connectors)

ARG15 (15 ft. RG-8/X - Belden 9258) 1.4 dB

ARG25 (25 ft. RG-8/U - Belden 9913F) 1.9 dB

ARG50 (50 ft. RG-8/U - Belden 9913F) 2.8 dB

ARG100 (100 ft. RG-8/U - Belden 9913F) 4.6 dB

ARX125 (125 ft. RG-8/X - Belden 9258) 12.5 dB

Orientation

A wireless transmitter antenna is generally oriented verti­cally, therefore, the ALP should also be oriented verti-

cally. The transmitter antenna should be parallel with the
plane of the ALP antenna as depicted below.

Typical Horizontal Pattern

Typical Vertical Pattern

Specifications

ALP500, ALP620

Pattern Gain: +7dBi (isotropic)
+4dBd (over dipole)

Range: 450-862 MHz
Weight: ALP500: 14.2 oz.

ALP620: 9.4 oz.
ALP650/E Series: 12 oz.

Connector: 50 Ohm BNC
Dimensions: 12” high x 10.5” deep x 1.5” wide

(ALP650 without mounting hardware)

ALP650 Series with RF Amplifier

Pattern Gain: +7dBi (isotropic)
+4dBd (over dipole

Passband:

ALP650L/E (RoHS compliant) 470.000 - 692.000 MHz
ALP650M/E (RoHS compliant) 537.000 - 768.000 MHz
ALP650H/E (RoHS compliant) 640.000 - 862.000 MHz

RF Gain: +12 dB with 0dB attenuator
+8 dB with 4dB attenuator
+5 dB with 7dB attenuator

Third Order Intercept: +27 dBm @ input (+41 dBm output)
Weight: 12 oz. (all versions)
Power Requirements: 8V to 16V DC at the input jack;

auto reset poly fuse protection circuit;

constant power switching supply

• 8V DC (125 to 145 mA)

• 12V DC (83 to 106 mA)

• 14.4V DC (69 to 89 mA)

• 16V DC (60 to 80 mA)
Phantom Powering: DC voltage supplied via coaxial cable by

UMC16B,
VRM input jack or BIAS-T power inserter
(70 to 80 mA)

Power Consumption: 1.2 Watt nominal (switching regulator)

The ALP650 Series antennas have been tested and
found to comply with the limits for a Class B digital de­vice, pursuant to Part 15 of the FCC Rules. These limits
are designed to provide reasonable protection against
harmful interference in a residential installation. However,

there is no guarantee that interference will not occur in a
particular installation. The antenna generates, uses and

can radiate radio frequency energy and, if not installed

and used in accordance with the instructions, may cause

interference to radio receivers. Changes or modications
to this equipment not expressly approved by Lectroson­ics, Inc. could void the user’s authority to operate it.

581 Laser Road NE • Rio Rancho, NM 87124 USA • www.lectrosonics.com
[phone] • [phone] • fax [phone] • [e-mail]

If this equipment does cause harmful interference to
radio or television reception, which can be determined by
turning the equipment off and on, the user is encouraged

to try to correct the interference by one or more of the
following measures:

• Reorient or relocate the receiving antenna

• Increase the separation between the equipment
and receiver

• Connect the equipment into an outlet on a circuit
different from that which the receiver is connected

• Consult the dealer or an experienced radio/TV

technician for help

Applies to:

ALP650L/E, ALP650M/E

and ALP650H/E

25 September 2012