140 Options List
C.12 Option 20: Fiber Optic Output, type ST 820nm
C.12.1 Purpose
When installed into the standard Model 1084A/B/C, Option 20 provides one selectable fiber-optic
output with Type ST connector and 820-nm transmitter compatible with multimode fiber.
C.12.2 Specifications
One fiber-optic output is jumper-configurable to each of the standard digital (CMOS) signal out-
puts: IPPS, IRIG-B unmodulated and IRIG-B Modified Manchester(IEEE P1344 High-Precision
Time Code). Analog signals, IRIG-B Modulated, and ±5 V Recorder are not selectable.
Option 20 provides an optical power output of -15 dBm minimum (-12 dBm typical) into 62.5/125-
µm fiber. The transmitter is also usable with 50/125µm, 100/140µm and 200µm PCS fiber.
The optical signal is ON whenever the selected logic signal is HI. Transmitter bandwidth is compat-
ible with all available logic signals. Fiber optic signal may be converted back to electrical format
using the Model 10881A Fiber Optic to Logic converter, available separately from Arbiter Systems.
C.12.3 Output Jumper Configuration (JMP2)
Select standard digital (CMOS) output signals for output via the fiber-optic output transmitter by
setting jumper JMP2 on the main board. The following table provides a list of digital available
and jumper locations for configuration to a fiber-optic output connector.
Position Signal
A IRIG-B Unmodulated
B IRIG-B Modified Manchester
C 1 PPS