Lectrosonics Active/passive LPDA antenna with selectable RF gain and filtering
The Lectrosonics ALP690 is a high-performance active/passive UHF LPDA (Log Periodic Dipole Array) antenna with a built-in RF amplifier to extend the operating range of wireless microphone receivers or base station transmitters in location or studio productions. The unit delivers +4 dBd of passive gain, while the built-in RF amplifier can be engaged to supply -6 to +12 dB of gain in adjustable 1-dB steps for overcoming signal loss in long coaxial cable runs.
The antenna is powered via DC bias inserted on the coaxial cable connected to the 50-Ohm BNC jack. This power can be supplied by a Venue Series receiver, an active multicoupler, or an inline BIAS-T device. The unit automatically switches to passive mode when no DC power is present on the coaxial cable, allowing you to use it not only for receivers but for IFB or IEM transmission applications as well.
A membrane switch keypad and LED readout on the control panel allow for quickly adjusting RF amplifier gain, filter bandwidth, and display brightness—convenient when working in low-light environments. As an active antenna, the ALP690 operates with a broad bandwidth to accommodate multi-channel systems. The filter bandwidth is adjustable from 470 MHz at the lower end to either 608 or 700 MHz at the top end for use in the US market or abroad.
The skeletal frame reduces wind load and is constructed with copper traces on a .133" thick glass epoxy high-pressure thermoset plastic laminate material with a durable finish. The ALP690 can be mounted horizontally or vertically with the supplied mount or an optional mounting adapter kit (sold separately).
Features and Functions
- Skeletal frame reduces wind load
- Passive directional gain of +4 dB
- Active gain from -6 to +12 dB, adjustable in 1-dB steps
- Negative gain for offset and close proximity transmitters
- Adjustable bandwidth from 470 MHz to 608 or 700 MHz for world-wide use with multi-channel systems
- Control panel with membrane keypad and LED for low-light operation
- Requires 8 to 16 VDC bias power from Venue Series receiver, active coupler, or inline BIAS-T
- Vertical or horizontal mounting
Isotropic: +7 dBi
Over Dipole: +4 dBd
Passive: 450 - 850 MHz
Active: 470 - 608 or 470 to 700 MHz (Selectable)
Range: -6 to +12 dB in 1-dB Steps
Third Order Intercept
+27 dBm @ Input; +41 dBm Output
DC Bias on Center pin of Coaxial Cable
8 to 16 VDC
1.5 W Max
13 oz / 355 g
Not Specified by Manufacturer