DAI-2 by Sine Systems, Inc.

The DAI-2 allows station personnel to perform a remote broadcast from an ordinary telephone with no assistance at the studio. But with the array of features included, its uses are unlimited! The DAI-2 combines a telephone autocoupler, a DTMF tone operated controller, audio switching, alarm sensing and output relays into an extraordinarily flexible system.

The DAI-2 consists of our Dial-up Audio Interface controller and an integrated relay panel. Our experience with this product has shown that engineers are not interested in building a custom relay panel when a simple alternative is available. We’ve designed the relay panel to be as easy as possible to install while still maintaining the full flexibility of the system. Then, we combined it with the DAI control unit into a single space rack panel. The result is a small, elegant package with more functionality than the original!

The DAI combines these functions as necessary to perform complex actions at the press of a single button on an ordinary telephone. The system is fully programmable. You specify what should happen for each different key.

At the press of a button the DAI can:

Open or close any or all of the audio/control relays
Route audio from one or more external sources to the telephone line
Route audio from the telephone line to one or more destinations
Report the status of logic inputs

Without user intervention, the DAI can monitor the logic inputs and perform tasks based on a status change of the input signals. Logic inputs can cause the DAI to:

Call up to four telephone numbers to report an alarm condition
Open or close any or all of the audio switching/control relays

The DAI can even connect to the telephone line under the command of an external device. This allows the DAI to be ‘keyed’ from an RPU or connected to a leased telephone circuit. This opens up even more possibilities for remote use. The DAI can send audio to, or receive audio from, the telephone line but it is not a telephone “hybrid” device and cannot do both at the same time.

Optional Accessories

In installations where audio from the DAI will be put on air the optional DB-1 Delay Board is useful. The DAI mutes the audio output whenever a DTMF tone is present. However, since it takes about 40 milliseconds to detect and validate the tone, the first 40 milliseconds of the tone appear at the audio output. With the DB-1 option installed, the audio output is delayed 50 milliseconds so the output is muted 10 milliseconds before the tone arrives. This allows unlimited use of DTMF control tones without ever hearing them on the air. If an announcer is monitoring off the air there will be delay of 50 milliseconds. Some announcers can handle this as little more than a minor annoyance but others will find it highly offensive. To allow for professional personality variations, the delay can be bypassed.

Another option that is useful in some installations is the CI-1 Composite Insertion module. A composite FM signal is routed through the CI-1. When the CI-1 is activated by the DAI, an external audio signal is inserted into the air chain. The CI-1 also contains an internal soft-clipper and an insertion level control so that downstream equipment is not overloaded. Connections to this device are made through BNC connectors and screw terminals. It is housed in a small, metal chassis. When the CI-1 is not active, it appears to be a shielded, straight wire.

The DAI has a logic level input that can be used to force the telephone line off hook. This is useful when the DAI needs to share a telephone line with another piece of dial-up equipment, such as the RFC-1/B Remote Facilities Controller. Using this arrangement, it is easy to call the RFC-1 and then switch over to the DAI.

Any of the commonly used bandwidth extenders (such as Comrex) can be used with the DAI. In fact, the control capabilities of the DAI can be used to enable and disable the bandwidth extender. The DTMF control tones must be inserted in the system so they will arrive at the DAI at the correct frequencies.

The DAI-2 is an inexpensive and practical way to improve efficiency and lower operating costs at your facility. Keep in mind that the uses we have discussed are only examples. You may come up with entirely different applications.








		Perform remote broadcasts from an ordinary telephone The DAI-2 allows station personnel to perform a remote broadcast from an ordinary telephone with no assistance at the studio. But with the array of features included, its uses are unlimited! The DAI-2 combines a telephone autocoupler, a DTMF tone operated controller, audio switching, alarm sensing and output relays into an extraordinarily flexible system. The DAI-2 consists of our Dial-up Audio Interface controller and an integrated relay panel. Our experience with this product has shown that engineers are not interested in building a custom relay panel when a simple alternative is available. We’ve designed the relay panel to be as easy as possible to install while still maintaining the full flexibility of the system. Then, we combined it with the DAI control unit into a single space rack panel. The result is a small, elegant package with more functionality than the original! Here are some of the features of the DAI-2: Integrated relay panel and single space rack unit chassis Relay status indicators on the front panel 1 ganged DPDT relay for stereo audio switching 7 DPDT relays for audio switching and control 3 factory-programmed command sets 1 fully user-programmable command set Momentary or latched relay outputs 4 logic level inputs DTMF tone decoder Balanced audio input and output Automatic level control for telephone line audio Cue tone generator External connections made through screw terminals The DAI combines these functions as necessary to perform complex actions at the press of a single button on an ordinary telephone. The system is fully programmable. You specify what should happen for each different key. But wait, there’s more... At the press of a button the DAI can: Open or close any or all of the audio/control relays Route audio from one or more external sources to the telephone line Route audio from the telephone line to one or more destinations Report the status of logic inputs Without user intervention, the DAI can monitor the logic inputs and perform tasks based on a status change of the input signals. Logic inputs can cause the DAI to: Call up to four telephone numbers to report an alarm condition Open or close any or all of the audio switching/control relays The DAI can even connect to the telephone line under the command of an external device. This allows the DAI to be ‘keyed’ from an RPU or connected to a leased telephone circuit. This opens up even more possibilities for remote use. The DAI can send audio to, or receive audio from, the telephone line but it is not a telephone “hybrid” device and cannot do both at the same time. Optional Accessories In installations where audio from the DAI will be put on air the optional DB-1 Delay Board is useful. The DAI mutes the audio output whenever a DTMF tone is present. However, since it takes about 40 milliseconds to detect and validate the tone, the first 40 milliseconds of the tone appear at the audio output. With the DB-1 option installed, the audio output is delayed 50 milliseconds so the output is muted 10 milliseconds before the tone arrives. This allows unlimited use of DTMF control tones without ever hearing them on the air. If an announcer is monitoring off the air there will be delay of 50 milliseconds. Some announcers can handle this as little more than a minor annoyance but others will find it highly offensive. To allow for professional personality variations, the delay can be bypassed. Another option that is useful in some installations is the CI-1 Composite Insertion module. A composite FM signal is routed through the CI-1. When the CI-1 is activated by the DAI, an external audio signal is inserted into the air chain. The CI-1 also contains an internal soft-clipper and an insertion level control so that downstream equipment is not overloaded. Connections to this device are made through BNC connectors and screw terminals. It is housed in a small, metal chassis. When the CI-1 is not active, it appears to be a shielded, straight wire. The DAI has a logic level input that can be used to force the telephone line off hook. This is useful when the DAI needs to share a telephone line with another piece of dial-up equipment, such as the RFC-1/B Remote Facilities Controller. Using this arrangement, it is easy to call the RFC-1 and then switch over to the DAI. Any of the commonly used bandwidth extenders (such as Comrex) can be used with the DAI. In fact, the control capabilities of the DAI can be used to enable and disable the bandwidth extender. The DTMF control tones must be inserted in the system so they will arrive at the DAI at the correct frequencies. The DAI-2 is an inexpensive and practical way to improve efficiency and lower operating costs at your facility. Keep in mind that the uses we have discussed are only examples. You may come up with entirely different applications.