AH-5A BOGEN COMMUNICATIONS, AH-5A Datasheet - Page 78

• Manufacturer Part Number: AH-5A
• Description: Amplified Speaker/horn
• Manufacturer: BOGEN COMMUNICATIONS

Specifications of AH-5A

• Peak Reflow Compatible (260 C): No
• Leaded Process Compatible: No
• Lead Free Status / RoHS Status: Contains lead / RoHS non-compliant

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TELEPHONE INTERFACES
The most common way to make announcements over a paging system is through the telephone system. It is a convenient
and readily available live input source. However, audio and telephone technologies are different. This sometimes makes
it necessary to use an adapter to link the two systems together.
There are many types of telephone ports possible in telephone switches. The four types presented here – Page Port, Loop
Start trunk, Ground Start trunk, and Analog ring-up station – are the only ones Bogen recommends as interfaces to
telephone systems. Other port types and specifically digital station ports are not suitable for connection to amplifiers and
interface devices.
Page Ports
Loop And Ground Start
Analog Station
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acknowledgment handshake for making the initial connection
than other methods
used — one limits the maximum length of the page to ensure disconnection,
of silence
control contact closure
control the muting of background music
equipment have voice-activated (VOX) functions such as background
music muting
(bi-directionality is necessary when including talk back capability in
the trunk and connects the amplifier to the trunk port through
signal conditioning electronics
and immediately disconnects the amplifier from the trunk
and loop current to the trunk port
in telephone line voltage between on- and off-hook conditions
a trunk port is available
which indicates to the interface that the caller has disconnected;
Dedicated audio output available standard on most telephone systems
Can be connected directly to the input of most amplifiers
Traditionally a 600-ohm dry audio signal and a normally open
Control contacts, if available, activate during a page and typically
Some page ports provide only an audio pair, which requires that audio
Paging ports are not always bi-directional like telephone lines
Not all paging ports will produce DTMF tones which are necessary
The Loop Start, or CO port, is the most popular type of paging interface
to use when a page port is not available or suitable
A Ground Start trunk uses loop current but employs a request and
An interface device is necessary when connecting a trunk to an amplifier
When paging, an interface adapter detects the off-hook condition of
When the trunk is released, the adapter detects the on-hook condition
Trunk interface adapters require a power supply to provide talk-battery
A pop at the end of a page is typically present due to the large change
An analog station allows interfacing when neither a paging port nor
Analog ring-up interfacing requires a more sophisticated interface
The interface must detect a high-voltage ring signal and answer the call
to start the page
To determine when to disconnect the page, typically two system timers are
the other senses audio activity and disconnects after a preset length
Many telephone switches now provide a calling party control (CPC) signal,
Bogen interfaces disconnect immediately upon detecting a CPC signal
when using zone paging equipment
a paging system)