MITS Janus Time Engine
Page 11 of 39
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1.2
Photo-Sonics Interface (PSI/O)
Controls and data received from the JTE Master Controller I/O Interface ensure properly
synchronized timing and frequency outputs.
The PSI/O also receives differential 1PPS and B00x signals and delivers them to the JTE Master
Controller for time master synchronization.
1.2.1
Time code and frequency output ports
The PSI/O provides multiple time outputs that are to be simultaneously available each aligned to
the time master.
The time code and frequency outputs are as follows.
Output
Characteristics
Notes
1PPS
10 Ω, TTL buffered output capable of
driving 10 TTL loads. Short circuit
protected.
SE output termination 50 Ω
DE output termination 120 Ω
Programmable phase as rising edge
aligned to 1-second tick or falling
edge to 1-second tick.
This is a dual output where a set of
pins is TTL and the other is
differential. Both outputs are
active.
Clock A
10 Ω, TTL buffered output capable of
driving 10 TTL loads. Short circuit
protected.
SE output termination 50 Ω
Frequency is programmable from
1Hz to 10 MHz in decade steps.
Programmable phase as rising edge
aligned to 1 second tick or falling
edge to 1 second tick.
Clock B
10 Ω, TTL buffered output capable of
driving 10 TTL loads. Short circuit
protected.
SE output termination 50 Ω
Frequency programmable from 1Hz
to 999 Hz in 1 Hz steps.
Programmable phase as rising edge
aligned to 1 second tick or falling
edge to 1 second tick.
IRIG B007
10 Ω, TTL buffered output capable of
driving 10 TTL loads. Short circuit
protected.
SE output termination 50 Ω
DE output termination 120 Ω
This is a dual output where a set of
pins is TTL and the other is
differential. Both outputs are
active.
IRIG B127
75 Ω, transformer isolated.
Programmable carrier output from
1 Vp-p to 9.9 Vp-p.
The disciplined drive frequency (NCO output) and fractional second roll over are used to phase
lock and accurately synchronize all the above outputs.
