Anywhere you need...
- To Switch to a Secondary Video Source
- To Detect Loss of Video
- Automatic Switch over
- Detection of NTSC or PAL Signals
- Operation from AC or DC Power
The TX-AVX is part of the group of versatile TX series from Radio Design Labs. TX series feature the advanced circuitry and high quality connectors for which RDL products are known. The ultra-compact TX series can be mounted in limited space using the adhesive methods popularized by RDL's STICK-ON™ series. The TX-AVX may be mounted directly to a backboard using optional mounting brackets available from RDL.
APPLICATION: The TX-AVX is the ideal choice in installations where automatic switch over to an alternate video source is needed when the primary signal is lost. The unique power supply input allows the TX-AVX to be powered from a wide variety of existing ac or dc power sources.
The TX-AVX has two video inputs and a single output. The detection circuit bridges the INPUT line. When a valid NTSC or PAL video signal is detected, the INPUT jack is connected to the OUTPUT jack. The output is designed to connect to a 75 ohm terminated load. In the absence of video input at the INPUT jack, the AUX INPUT jack is connected to the OUTPUT jack. The switching is accomplished by means of a high quality RF relay. If power to the TX-AVX is interrupted, then the AUX INPUT jack is connected to the OUTPUT jack. The INPUT jack is 75 ohm terminated. The AUX INPUT is terminated when it is connected to the OUTPUT and is unterminated when it is not in use.
Video detection is based on valid sync signals. The TX-AVX responds to valid NTSC or PAL sync while ignoring 50 Hz and 60 Hz hum and related induction artifacts. The TX-AVX is able to detect signals as weak as ½ volt. When a valid signal is detected, the relay connects the INPUT to the OUTPUT, and provides a ground connection to the SLAVE terminal, permitting the module to be connected as a video presence detector.
The TX-AVX power supply input accepts an ac or dc voltage from 12 to 24 volts. 12 Vdc batteries may power the TX-AVX in broadcast applications; a common low-voltage ac supply may power the module together with the camera in security installations provided the camera is internally ground-referenced. The TX-AVX is a negative ground-referenced product. In the unlikely event it is connected on a common ac supply together with a camera which is positive Ground-referenced and not transformer isolated, a ground fault may occur. The TX-AVX automatically detects such a fault, disconnects itself from the power input, and illuminates the FAULT LED This alerts the installer to transformer isolate the TX-AVX power source from the camera power source. This unique circuit protects both the camera and TX-AVX from damage. RDL's available PS-24 power supply may be used to power the module when isolation is required, or in any other installation.
Use the TX-AVX individually in NTSC or PAL systems, or combine it with other RDL Rack-Up®, STICK-ON, TX series and various mounting accessories as part of a complete audio/video system.
Power supply is separate.
