Intercoms For Access Control & Security

Applications include vehicle entry gates and healthcare providers like managed care facilities.

This client provided rehab and extended care to its clients. Weekends were particularly challenging because besides having to maintain their normal activities, the staff had to control a lobby door which remained locked at all times to prevent patients from wandering off and also to admit other staff, visitors and EMS workers.

A reliable video intercom was in order. The intercom station in the lobby was located adjacent to the controlled door. The intercom base unit was located at the primary nurse’s station. This particular nurse’s station was always staffed since the patients in this wing required a higher level of care than on other wings. Also being constantly staffed, this position was considered the after hours command post from which care meals and drugs were dispensed.

The Aiphone MK-1GD is used as the nurse base station, and an Aiphone MK-DV is used in the lobby.  This is a fixed-camera black and white video intercom which provides the cost-effective, reliable operation this facility requires.

Frequently nurses are out on the ward, so we added an IER-2 Chime Extension Speaker to the base unit so the nurses are sure to hear when a visitor presses the Call button. The IER-2 has its own volume control, so when the nurses are all near the intercom, they can turn the volume of the call button down, or when they are not close by they can turn the volume up.

The MK-1GD has and integral unlock button for controlling the locking mechanism at the door. In this application we are triggering an input on an access controller. If the intercom is going to control a locking device directly by switching voltage on and off, an optional slave relay is recommended. This spares the internal contacts on the Aiphone the wear and tear of the high current and surge associated with powering strike and maglocks, which would shorten the life of the unit, and also generate noise over the communications line.
For more information, contact Aiphone Corp., 1700 130th Ave. NE, Bellevue, WA 98005. Telephone: 425-455-0510 or 800-692-0200. Web Site:

Emergency communications is a priority for universities as well as other entities such as manufacturing complexes, commercial industrial parks, shopping malls, hospitals and mass transit. 

Responsibility for a student, employee, patient or customer’s well-being does not end at the door of the facility. Emergencies can be as mundane as a car which refuses to start or as critical as a medical crisis, or criminal act. The Security team needs to know there is a problem before they can take action, and emergency communications systems help to fulfill this need.

Talk-A-Phone Co.’s Wide-Area Emergency Broadcast System (WEBS®) is a family of mass notification devices that can be integrated into a comprehensive emergency communication system for a multitude of locations. WEBS units can be situated in a variety of mounts and locations, bringing security coverage to heretofore-neglected corners of a facility. Tone or voice messages can be delivered to specific units, regions, or to all units at once, allowing for flexible emergency response.

Analog and Native IP versions are available. WEBS models can also be made wireless with Model VOIP-RF, extending security’s footprint even further. The wide array of installation options makes WEBS a valuable security instrument at college and corporate campuses, mass transit locations, and parking facilities. WEBS installations can also be integrated with surveillance cameras and strobe lights for robust coverage. Tower, wall and pedestal mounts are available.

For more information, contact Talk-A-Phone Co., 5013 N. Kedzie Ave., Chicago, IL 60625. Telephone: 773-539-1100. Web Site:

Intercoms are essentially elements of the telecom system. Viking Electronics manufactures devices which combine intercoms, security and door control.

The Viking Electronics SRC-1 enables a standard touch-tone phone to securely operate a set of timed relay contacts to control a door strike or gate controller at a remote location.

The SRC-1 is fully user programmable and uses non-volatile memory. It eliminates the possibility of dialing the activation code through the entry phone using a hand held touch tone dialer.

The SRC-1 features a switchable 32V talk battery to allow use with any of Viking’s entry phones (E Series), door boxes (W Series) or hot-line/panel phones (K Series).

The SRC-1 is installed between the entry phone and the secure phone, and will reject touch tones from the entry phone and only operate the relay if the correct activation code (user programmable) is given from the secure phone. The SRC-1 also provides up to 32 keyless entry codes to operate the relay from the entry phone with 1 to 6 digits. This feature can be disabled in programming for increased security.
Locksmith Ledger interviewed Viking Electronics SRC-1 product manager James Catt about this product. Following are our questions and his answers.

Can you tell us about the SRC-1?
The SRC-1 is a new product for this year. It needs to be used with an entry phone (E-10A, E-30, E-60, K-1700-3, etc.) or doorbox (W-1000, W-2000A, W-3000) (sold separately) and adds remote touch tone control of a door strike to an existing or new installation.

What type of device is this dialer that can be used to trick telephone entry systems?
The handheld touchtone dialer is a product that is getting rarer to find, but can now be emulated by PDAs and cell phones. It is simply a device capable of producing DTMF tones through a speaker that is held up to the microphone of the entry phone.

What entry systems out there are vulnerable to this form of attack?
Any entry system that relies on touch tones to activate the door strike or gate controller that does not attempt to verify the direction of the detected tones. This allows either the caller or the operator to activate the device with the correct touch tones. The normal methods to prevent the caller from activating the door strike are either obfuscation by keeping the activation code secret, or not providing the caller with a keypad. However, the handheld dialer circumvents the no keypad protection method.

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