Giga-tronics Series 12000A, Operation Manual

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Series 12000A Microwave Synthesizers
2-30 Publication 31231, Rev. J, October 2003
2.3.10.2 ALC Mode
This field allows choosing between leveled power and maximum power. In the leveled power mode, the
output power (modified by the Power Slope and/or Offset parameters) is set by the operator. When
Maximum Power is selected, the instrument will produce the highest power possible. The Level LED
remains on when in Maximum Power mode.
2.3.10.3 Sensor
Currently, only the internal sensor is supported.
2.3.10.4 Attenuator Mode
This field selects either Automatic or Manual operation of the step attenuator. In Automatic mode, the
step attenuator will switch to 10 dB when the set power is between –10 and –.01 dBm. It will continue
to increase its attenuation value for each 10 dB ‘block’ of settings. In Manual mode, the step attenuator
may be fixed at any desired setting from 0 to 110 dB. Once this is done, the incremental power
adjustment range is –20 to +20 dB. This means that the instrument leveling system is effectively
controlling the power from a value of –20 dBm to +20 dBm. Power levels from –20 to –10 dBm may not
meet the leveling accuracy specification. Power levels above the specified maximum output for any
given frequency may not be attainable.
2.3.10.5 High Power
This menu item is only visible if Option 20 has been installed. Option 20 provides additional amplifiers
to gua20 dBm minimum output. When the selection is ‘Automatic’, the high power amplifier
will switch in at +15 dBm. This is done to reduce amplifier noise at lower levels. In the ‘Disabled’
mode, the high power amplifiers never switch in.
2.3.10.6 Power Slope
When this function is enabled, the following screen appears:
The purpose of this function is to allow compensating for losses in some external component, such as a
cable. The ‘Slope’ field defines the amount of change per GHz (The maximum allowed is 8 dB).
Figure 2-18: Power Slope Selection