Data Broadcast Switch

8 to 32 Port Data Broadcast Switch for RS-232 async data transfer

  • 8 to 32 ports
  • Up to 9600 bps port speeds
  • 1 control port, 1 data download port
  • Ideal for paging transmitter, SCADA, and machine control applications
  • Connects to any other async devices
  • Optional 48V power supply


Input Control Port
Output Ports
Port Specifications
Indicators and switches (front panel)
Control Port Commands




The DCB Data Broadcast Switch is a 8 to 32 port data broadcast device that allows all output ports to become reverse channels upon command. It was designed for use with paging systems, where paging data must be replicated to many remote paging terminals. Built upon the proven DCB Access Switch platform, it includes a control port, allowing reverse channel communication from any of the selected downstream paging terminals. The reverse channel selection is typically used for remote management of the remote devices such as paging transmitters.

The Broadcast firmware is available for 8, 16, 24 or 32 ports. Ports are async 9600 bps, 8 data bits, no parity, one stop bit. Data to be broadcast enters the Switch on the "Network Composite Port". Data is replicated on the output ports 1 through 8, 1 through 16, 1 through 24 or 1 through 32. The "Network Management Port" is a control port used to select reverse channel input. Reverse channel input can come from none or only one of the output ports, and goes out the "Network Composite Port". The reverse channel often carries reports and transmitter information back to the head-end computer.



DB-08 - 8 port model
DB-16 - 16 port model
DB-24 - 4 port model
DB-32 - 32 port model

Output Ports

Each Switch contains from 8 to 32 output ports. These ports are RS-232 implemented on RJ-45 connectors. Data entering the Switch on the input port is sent to all output ports. Optionally, one output port at a time can be used as a source for data transmitted back to the input port (see Operation).

DB-08 - 8 ports
DB-16 - 16 ports
DB-24 - 24 ports
DB-32 - 32 ports

Port Specifications

Data Format:

1 Start bit
8 Data bits including parity if used
1 Stop bit
10 Bits total

Data Rate:

Fixed: All ports (input and output) fixed at 9,600 bps

Interface: CCITT V.24, RS-232D
Connectors: RJ-45 (8-wire)

Indicators and Switches (front panel)

Power Indicator
Reset Switch


Data is normally passed one way from the input port to all output ports. This is the default state, and this state can entered by entering the characters"00 " at the control port. A second mode, "reverse channel", is enteredwhen a two character port number is received at the control port. Allowable control port entries are "00" through "32" (followed by or ). "00" returns to the default one-way transmitting state. Any other acceptable entry (numbers between 1 and the highest port number present) places the Switch in reverse channel mode. When in reverse channel mode data received on the reverse channel port is passed out the input port. There is a full duplex communications channel between that reverse channel port and the input port during this mode. This operation continues until a "00" is received on the command port to switch back to normal mode.

Control Port Commands

The command port accepts only two characters followed by a carriage return or carriage return/line feed pair . The two characters are a number between 00 and 32 (the ASCII characters "00", "01", ... "32").

"00" returns the Switch to normal broadcast operation mode. "01" through "32" puts the Switch in reverse channel mode with the number being the port number to accept data through.


Temperature -40 to +75 C, non-condensing
Power requirements: 120 VAC, 30-43 watts, .25-.36 amps
48 VDC Power supply optional
10 1/4" x 9 3/4" x 2 1/4" (AS-04, AS-08 and AS-16)
10 1/4" x 9 3/4" x 4 1/2" (AS-24, AS-24M and AS-32S)

Rear view of Data Broadcast Switch DB-32 (32 port)


Applications Notes Covering DCB Access Switch Products

Saving Time and Money... The DCB Access Switch and Remote Maintenance
Ways to save money and time by using the DCB Access Switch.


DB-08 8 Output Ports $ 995
DB-16 16 Output Ports $ 1,495
DB-24 24 Output Ports $ 1,995
DB-32 32 Output Ports $ 2,495
PS-48 48 Volt Power Supply Option $ 75
PS-48 48 Volt Power Supply (Replacement) $ 125
All Data Broadcast Switchs use RJ-45 connectors.

Data Comm for Business Inc.
2949 County Road 1000 E
Dewey, Il 61840
Voice: 217-897-6600
Toll Free: 800-4-DCB-NET
Toll Free: 800-432-2638
Email: Contact Page
Fax: 217-897-8023
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