The STA-III Plus provides a convenient interface between a telephone line and the user’s equipment. Features include auto-answer after a user programmed number of rings, user programmed numeric DTMF access code and relay and audio in/out control via numeric DTMF commands.

Main Features:
• Auto-answer and auto-disconnect via CPC (calling party control) and/or long dial tone hang up signals, allowing use behind analog
• PBX switches and POTS lines.
• Front panel, plus remote line seize and drop control for manual operation.
• Electronic telephone hybrid.
 • Remote controllable send and receive audio.
• Balanced bridging audio input with front panel level control.
• Balanced low Z audio output with front panel level control.
• Front panel LED’s display power, hook, ring and valid DTMF tone.
• Two remote controllable SPDT relays • SPDT End of Call relay.
• External SPDT hook relay activates when a valid access code is entered.
• Remote line busy input.
• User programmable number of rings before auto-answer.
• User programmable access code, up to 10 digits.
• Loop-thru phone jack.
• Plug-in euro-block screw terminals for audio and remote control connections, mating plugs supplied.
• Fully RFI proofed.
• Surge protected internal power supply, 12 VDC universal switching power supply with domestic connectors supplied. International AC connectors optional.
• Each unit may be set on a desktop, mounted on a wall or rack-mounted with the optional RA-1 rack shelf for mounting up to three units in 1-RU