Comtech EF Data CST-5000 - Manual (Page 99)

Theory of Operation CST-5000 C-Band Satellite Terminal
5–10 Rev. 9
5.1.6 Test Points and LEDs
Refer to Section 6.1.
5.2 High Stability Oscillator
The high stability oscillator provides a low phase noise, frequency-stable 10 MHz source
for the up converter, down converter, synthesizers, and IFLO.
The internal oven, which is provided for additional stability, operates directly from the
12V power source. The electronic control circuitry is buffered by an active filter.
The sinewave output is converted to a CMOS square wave before being output to the
synthesizers.
Refer to Figure 5-4 for a block diagram of the high stability oscillator.
5.2.1 Specifications
Frequency 10 MHz
Frequency Stability -40 to +70 ° C (-40 to 158° F)
Output Level CMOS voltages (+5V)
Output Waveform Square Wave
Input Voltage 12.5V
Input Current 600 mA at turn-on, 250 mA after warm-up at +25 ° C (77° F)
Warm-up 2.5 minutes to within 1 x 10 -7 of final frequency at +25 ° C (77° F)
Phase Noise (Maximum) 1Hz
Measurement bandwidth measured at 10
MHz:
10 Hz
100 Hz
1 KHz
10 KHz
-120 dBc
-150 dBc
-160 dBc
-165 dBc
Vibrational Sensitivity 1 x 10 -9 /g
Aging 5 x 10 -10 /day, 1 x 10 -1 /year
Frequency Deviation (mechanical) To compensate for 10 years aging
Frequency Deviation (electrical) ± 2 x 10 -6 minimum, 0 to 10 VDC