VERSITRON FOM II Series Model F2238A/F2245A High Speed fiber optic modems provide synchronous or asynchronous data transmission at speeds up to 10Mbps, at distances up to 20Km with fully transparent operations. Supporting RS-530 or MIL-STD-188-114A(balanced) interfaces,these products multiplex clock and data signals. They operate as two-channel multiplexer/converters. For high-speed synchronous operation, the first channel is used for data and the second is used for the transmit clock. Both channels may be used for data in low-speed asynchronous operation, typically at less than 100Kbps.
Designed for a wide variety of applications, the F2238A and F2245A products can operate in one of three different modes: Automatic, Forced Asynchronous, or Forced Synchronous.
These products can currently be found in two unusual applications. The VERSITRON RS-530 F2245A FOM II Series singlemode devices are being used in the Arctic Circle. Other devices in this series are being used to transmit data for municipal water flow monitoring equipment that determines operation of water pump controls to ensure a constant flow from the water source to the treatment plant.
In the automatic mode the F2238A and F2245A products can operate at any asynchronous data rate from 20Kbps to 100Kbps and at any synchronous data rate from 56Kbps to 10Mbps. They will also operate with variable data rates that are sometimes found with high-speed telemetry systems. An internal clock monitor selects the source of the transmit clock. When no clock is present, the devices utilize an internal 10MHz reference signal as the clock. This assures a sufficiently large number of samples for minimum end-to-end timing jitter.
In the Forced Asynchronous mode the internal 10MHz reference is used. In the Forced Synchronous mode the internal reference is disabled and the transmit clock is used. The minimum data rate in this mode is 56Kbps.
Local and remote modems can be set to operate in different modes. For example, this permits operation in one direction at 10Mbps synchronous and 250Bps asynchronous in the other direction. After operating mode and interface options are selected, the units do not require further adjustments regardless of the data rate.
Both the F2238A and F2245A utilize SFP module technology and incorporate LC optical connectors. Color coded LEDs provide status indicators on the device's front panels. A convenient front panel switch selects loopback mode which connects the transmitter output to the receiver input. On the f.o. side of the device, the output of the f.o. receiver is connected to the transmitter. This allows for testing of nearly all of the circuits.