Oscillator; I/O Connectors; Timing Connector - Spectracom VelaSync 1232 User Manual

1.4 Technical Specifications
1.4.1.3

Oscillator

Table 1-1:
Accuracy to UTC
GPS)
Holdover Accuracy
After 4 hours
After 24 hours
Notes:
• Accuracy to UTC is measured by comparing the internal 1PPS with the GPS ontime point.
• When ordering a VelaSync unit, either an OCXO or Rubidium oscillator must be specified.
• The specifications are subject to a steady environment temperature.
1.4.2

I/O Connectors

1.4.2.1

Timing Connector

The pre-installed TSync-model 25-pin Micro D-Sub Connector, when combined with the
adaptor cable and breakout cable (both included), provides the following I/O options:
Inputs:
1 PPS Input
IRIG AM Input
6
Oscillator accuracies
(1 sigma locked to
(loss of GPS signal after 2 weeks locked, constant temperature)
1 Hz pulse, rising edge or falling edge active (selectable); 100 ns minimum
pulse width
Amplitude: 0 V to +5.5 V input range, +0.8 V
Input impedance: <150 pF capacitive
Accepts IRIG formats A, B, G; NASA36; IEEE 1344
Amplitude: 500 mV
p-p
Modulation ratio: 2:1 minimum, 6:1 maximum
Input impedance: 10 kΩ minimum
DC Common Mode Voltage: ±150 V
Input Stability: Better than 100 ppm
OCXO
50 ns
1μs
25 μs
, +2.0 V
VIL
to 10 V
p-p
maximum
DC
CHAPTER 1 • VelaSync User's Manual Rev. 3
Rb
25 ns
0.2 μs
1μs
VIH