Hello this is what I bought the DATALM from B&B Electronics to alert maintenance to downed communications. Know when you've got incoming data. Simply place the Data Alarm in the data line you want to monitor. It has DB25 female and male connectors with all 25 lines passing straight through so it can easily be added to any existing system. It can be set to detect data or absence of data on TD or RD on RS-232 communication lines, or the strobe on parallel communications. When the alarm condition is met, an LED turns on and a relay is tripped. Three Relay Terminals are provided - Common, Normally Closed or Normally Open positions. An audio alarm can be enabled to sound at the same time. The relay and alarm can be set to sound for a minimum period of time ranging from 1 second to indefinitely. A reset button is used to turn off the alarm. Measuring only 1.32"H x 2.40"W x 4.60"L, it fits easily next to your computer or printer. Requires 11 to 16 VDC at 80 mA. Power supply not included. Recommended Power Supply: 232PS 120VAC/60Hz to 12VDC @ 100mA,
2=2E5 mm plug, (+) Tip (UL/CSA approved).B&B Electronics
707 Dayton Road =B7 PO Box 1040 =B7 Ottawa, IL 61350 T 815-433-5100 F 815-433-5109this unit is no longer available from B&B i got the last one my question is where can i get more or the schematic to make it or have it made=20 any help would be greatly apprenticed thanks=20
grove