The Lectrosonics ALP690 is a high-performance active/passive 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 a passive antenna, the ALP690 is capable of operating in the 450 to 850 MHz bandwidth. As an active antenna, it operates with a broad bandwidth to accommodate multi-channel systems. This bandwidth is switchable between 470 to 608 MHz for the US or 470 to 700 MHz for worldwide use.
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 mounting block or an optional mounting adapter kit (available separately).
Features and Functions
- Skeletal frame reduces wind load
- Active gain from -6 to +12 dB, adjustable in 1-dB steps
- Passive directional gain of +4 dB
- Negative gain for offset and close-proximity transmitters
- Adjustable bandwidth from 470 to 608 or 700 MHz for worldwide 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
- Mounting block with 1/4"-20, 3/8"-16 tripods, and 5/8"-27 threaded openings (mounting block can be rotated 90°)