Comtech EF Data SPOD PS 1, PS 1.5, and PS 2 C-, X-, or Ku-Band - Manual (Page 94)

SPOD C-, X-, or Ku-Band Outdoor Amplifier MN-SPODPSX
Serial-based Remote Product Management Revision 1
5–2
5.2.2 Attenuator Control
The SPOD gain can be attenuated over its specified range by exercising the
ATT
command. The details for the format of this command
are found later in this chapter.
5.2.3 Mute Control
The SPOD may be muted via software or discrete control:
• Software – Exercising the
MUT=1
command will “software” mute the unit.
• Discrete Control – When exercising the AUX=1 command, the SPOD will be muted until Pin ‘S’ (on the ‘J6 | COM1’ Discrete Control
Connector) is pulled to ground (Pin ‘K’). At that time, the unit unmutes.
The Mute command provides over 60 dB of RF on/off isolation. However, the Mute command only turns off the first few low power
stages of the amplifier, the high power stages remain on. By allowing the higher power transistors to stay on, the SPOD remains in more
thermally stable state should the mute condition be removed.
If the user desires to completely turn off the bias to the entire amplifier (perhaps to conserve energy in a redundant system), both the
MUT=1
and
AMP=0
commands should be executed. For normal transmit operation,
MUT=0
and
AMP=1
are required.
5.2.4 Faults
The M&C system monitors certain key functions of the SPOD for proper operation. Should any of these parameters exceed
predetermined limits, the M&C system will declare a fault. The conditions that trigger a fault are:
• Any power supply more than ± 10% outside its nominal value.
• Fan less than 25% of maximum speed.
• I2C internal bus communications fault.