Description
The ST-VOX1 is an audio-controlled relay module designed to switch external circuits in response to voice or other audio signals. It accepts unbalanced microphone or line-level inputs and provides DPDT relay contacts plus an open-collector slave output. This compact STICK-ON series unit is optimized for talkback and intercom environments where automated switching is required.
Key features include voice-activated switching, adjustable sensitivity for mic and line inputs, and precise threshold adjustment using an on-board control. The unit offers both relay contacts and an open-collector slave output rated at 25 mA for driving indicators or remote logic. An audio threshold LED simplifies setup by showing when the device is triggered.
Technically the ST-VOX1 supports mic input sensitivity adjustable from -80 dBu to -50 dBu and line input sensitivity adjustable from -45 dBu to -15 dBu. Relay contacts are double-pole-double-throw and the unit handles up to 60 W switching power. Activation and delay timings are configurable to suit short speech bursts and expected talkback cadence.
Connectivity includes an unbalanced mic input and an unbalanced line input, plus a ground-referenced 24 Vdc power connection and an open-collector SLAVE output. The unbalanced outputs make it compatible with common preamps such as the STM-1 where the unbalanced STM-1 output can trigger the ST-VOX1 while balanced audio is carried separately. The unit is small and easy to mount in equipment racks or on surfaces.
Typical applications include intercom signaling, talkback control, LED indicator driving, and automated gating of external devices in broadcast or production environments. The ST-VOX1 is suitable for use in studios, control rooms, and fixed installations where voice-triggered switching improves workflow. It can be used to automate on-air lights, routing control, or to trigger recording equipment.
Installation is straightforward with clearly labeled inputs, outputs, and adjustments for sensitivity and release delay. The device operates from a ground-referenced 24 Vdc supply and functions reliably across a 0 C to 55 C ambient range. Rugged relay contacts, simple LED feedback, and compact dimensions make it an easy-to-integrate component in professional AV systems.