12
SYNC/ASYNC FIBER OPTIC MODEM
1. Specifications
Electrical Interface
Transmission Rates
—Asynchronous: 19.2, 28.8, 38.4, 57.6, and 115.2 kbps;
Synchronous: 19.2, 32, 48, 56, 64, 72, 96, 112, 128, 144, 192, and 256 kbps
Connectors
—RS530 via DB25 female
Optical Interface
Operating Wavelength—
850 nm for multimode fiber; 1300 nm for single-mode
fiber
Transmission Line
—Dual fiber optic cable
Budget (Maximum)
—- -18 dBm for 850 nm, 62.5/125 fiber; -18 dBm for
1300 nm; 9/125, 62.5/125 (LED) fiber
Receiver Sensitivity
— -48 dBm for 850 nm (LED); -50 dBm for 1300 and
1550 nm (laser diode)
Dynamic Range
—36 dB
NOTE
The ranges specified above were calculated according to the following
typical attenuation rates (with a 3-dBm margin):
3.5 dB/km for 850 multimode
0.4 dB/km for 1300 nm single mode
Connectors
—ST
®
Transmitter
—LED
Maximum Range
—850 nm (multimode) up to 7 km; 1300 nm (single mode)
up to 70 km
Diagnostics
Digital Loopback
—Local, activated by front-panel switch (DIG); Remote,
activated by front-panel switch (REM) or by the DTE interface signals (RS-530)
Analog Loopback
—Local, activated by front-panel switch (ANA) or by DTE
interface signal
