Giga-tronics 8650A Series, Operation Manual

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Front Panel Operation
Manual 31470, Rev. E, April 2001 2-9
RS-232:
Highlight the RS-232 option in the Power Meter Configuration menu and press [ Config ]. The RS-232
Config menu will display for configuration of the RS-232 interface.
1. Press [ Baud ] to set the Baud Rate. Select the desired rate with the up/down cursor keys. The default
value is 9600.
2. Press [ Length ] to set the Data Bits. Select the desired data bit length with the up/down cursor keys.
The default value is Press [ Parity ] and turn the parity on or off with the up/down cursor keys. Default
parity is off.
3. Press [ Stop bits ] to set the stop bit value. Select the desired stop bit value with the up/down cursor
keys. The default value is 1.
4. Press [ OK ] to accept the changes or [ Cancel ] to cancel the changes and return to the Power Meter
Configuration menu.
T Gate:
The Time Gate mode supplies a digital control voltage to enable or disable readings from any one or all
sensors. Thus, the mode limits a power measurement to a defined interval that is controlled by a start
time and a duration. The start time begins after a programmable delay following an external or internal
trigger.
Figure 2-5 illustrates the time gated measurement with an external time gated pulse applied to the
trigger input. In this mode, the time gate starts and ends with the input of a high or low TTL level input.
The duration of the measurement corresponds to the duration of the gated pulse.
NOTE:
The Time Gate feature operates only with modulation sensors.
Figure 2-5: Illustration of External Gating
☛ ☛ ☛ ☛
Gate
Time
Gate
Time
RF RF
Ext Gating
(TTL = High) Ext Gating
(TTL = Low)