Table: Configuration Commands lists the configuration command mnemonic codes. The system configuration selections made with GPIB commands remain in effect when the instrument is returned to local control.

The system configuration selections made with GPIB commands remain in effect when the instrument is returned to local control.

Table: List Sweep Commands lists the list sweep command mnemonic codes. These commands provide for (1) placing the signal generator in list sweep mode, (2) accessing up to four lists of 2000 frequency/power level sets, and (3) generating a phase-locked step sweep of the list frequency/power level sets.

In list sweep mode, up to four lists of 2000 non-sequential frequency/power level sets can be stored and accessed. A list index (0 thru 1999) identifies each frequency/power level set in a list. When commanded, the signal generator generates a phase-locked step sweep between the specified list start index and list stop index.

The command, LST, places the signal generator in list sweep mode. The ELN(x) command is used to select which of the four lists is to be accessed. The first list (list number 0) is the same list that is available via local (front panel) control. This list is stored in non-volatile RAM to preserve any settings after the instrument is powered off. The other three lists (list numbers 1, 2, and 3) are all stored in volatile RAM and all settings are lost when power to the signal generator is turned off. At power up, list numbers 1, 2, and 3 are set to their default state of 2000 index entries of 5 GHz at 0 dBm.

The ELI(xxxx) command sets the list index for the current list. Use the LF command to set the list frequencies starting at the list index and the LP command to set the list power levels starting at the list index. Any number of frequencies and power levels can follow these commands.

Another method of entering frequency and power level information into the current list index is to use the command, CTL, which copies the current CW frequency and power level to the current list index.

Programming “LST ELN1 ELI1234 LF 2 GH, 5 GH, 1 GH, 8 GH LP 2 DM, 9 DM, –3 DM, –10 DM” places the signal generator in list sweep mode, selects list number 1, and sets the list index to 1234. List index 1234 is set to 2 GHz at 2 dBm, list index 1235 is set to 5 GHz at 9 dBm, list index 1236 is set to 1 GHz at –3 dBm, and list index 1237 is set to 8 GHz at –10 dBm

Four different modes of triggering are available in list sweep mode—automatic, external, single, and manual. When automatic, external, or single trigger mode is selected, the output sweeps between the specified list start and stop indexes, dwelling at each list index for the specified dwell time. When manual trigger mode is selected, the list start index, list stop index, and dwell time parameter are not used. Instead, the list index is incremented using the UP command or an external TTL trigger and is decremented using the DN command.

The AUT command selects automatic sweep triggering and the HWT command selects external sweep triggering. When external sweep trigger mode is selected, the output sweep recurs when triggered by an external TTL-compatible clock pulse to the rear panel AUX I/O connector. The EXT command selects single list sweep triggering. When single sweep trigger mode is selected, a single list sweep starts when the TRG command is received.

The MNT command selects the manual trigger mode. In manual trigger mode, the list index is incremented by one each time the UP command is received or each time an external TTL trigger is received. The list index is decremented by one each time the DN command is received.

Generating a list sweep involves selecting a sweep range, a dwell-time-per-step, and a sweep trigger. The sweep range is defined by a list start index and a list stop index. Use the LIB(xxxx) command to set the list start index and the LIE(xxxx) command to set the list stop index. The dwell-time-per-step of the list sweep is changed using the LDT parameter entry command. Select a trigger for the list sweep using the list sweep trigger commands previously described.

Programming “LIB1234 LIE1237 EXT LDT 10 MS TRG” implements a list sweep from the current list index 1234 to index 1237 in single trigger mode with a 10 ms dwell-time-per-step, then triggers a single sweep.

During the initial sweep, the signal generator performs calculations to set the frequency and power levels. This causes the initial list sweep to take longer than each subsequent sweep. The command, LEA, initiates a process that examines every index in the current list and performs all the calculations necessary to set the frequency and power levels. This lets the initial list sweep be as fast as each subsequent sweep.

The list calculations are for the current list only. Any changes to the current list or selection of another list requires the calculations to be performed again. The calculations are stored only in volatile RAM and are lost when power to the signal generator is turned off.

 

Table: CW Frequency Commands lists the CW frequency command mnemonic codes. These commands call up each of the preset (or previously set) CW frequencies. Each command causes its associated CW frequency to be output and opens that frequency’s parameter for data entry.

 

 

 

 

 

 

Table: Analog and Step Sweep Commands lists the analog and step sweep command mnemonic codes. These commands are divided into five subclasses and are described in the following paragraphs.

Seven sweep ranges are available. The SF1 and SF3 commands select the sweep ranges of F1-F2 and F3-F4, respectively; the FUL command selects a full band sweep from the signal generator's low frequency limit to its high frequency limit.

The DF0, DF1, DF5, and DF6 commands each select a symmetrical frequency sweep around F0, F1, F5, and F6 respectively. The width of the sweep is determined by the ΔF frequency parameter.

Programming “F1 2 GH F2 8 GH SF1” sets F1 to 2 GHz, F2 to 8 GHz, and implements a F1-F2 frequency sweep.

Programming “DLF 6 GH F5 7 GH DF5” sets DF to 6 GHz, F5 to 7 GHz, and implements a F5-ΔF frequency sweep.

If the commanded step sweep range is invalid, a parameter error will be generated and the output of the signal generator will not be altered.

Assume that the MG362x1A had been previously programmed and was then executing an F1-F2 sweep. Programming “AF3” would then activate the F3-F4 sweep and cause it to alternate with the F1-F2 sweep.

Three modes of sweep triggering are available over the bus—Automatic, External, and Single. The AUT command selects automatic sweep triggering; the HWT command selects external triggering; and the EXT command selects single sweep triggering.

When automatic sweep triggering is selected, the sweep continually sweeps from its start frequency (or power level) to its stop frequency (or power level) with optimal retrace time.

When external sweep triggering is selected, a single sweep occurs when triggered by an external TTL-compatible clock pulse to the rear panel AUX I/O connector.

When single sweep triggering is selected, a single sweep starts when the TRG or TRS command is received. The RSS command resets the sweep to its start frequency (or power level), whenever the command is received while a single sweep is in progress.

 

Table: Frequency Marker Commands lists the frequency marker command mnemonic codes. These commands provide for (1) selecting a CW frequency as a potential marker, (2) selecting a potential marker as an active marker, and (3) individually turning markers on and off.

The ME1 command will enable a marker at the current frequency that is open for update; the ME0 command will disable the same marker. If a frequency parameter is not open, no action will be taken. The VM1 command will turn on video markers. The MK0 command will turn all markers off.

Table: Power Leveling Commands lists the output power leveling command mnemonic codes that include electing an RF output power level, leveling the CW output power, and turning the output power leveling off. In addition, commands are provided for the level offset and step attenuator decoupling functions.

 

The command, L1 calls up each of the preset (or previously set) output power levels. Each command causes its associated RF power level to be output and opens that power levels parameter for data entry. Each command will also deselect any other previously programmed power level and will turn off an active power level sweep.

The attenuator decoupling function provides for decoupling of the step attenuator (if equipped) from the
ALC system. The AT1 command decouples the step attenuator, the ATT(xx) command provides for setting the
step attenuator value for 0 to 110 dB in 10 dB increments, and the AT0 command deselects the attenuator
decoupling function.

 

Table: Stored Setup Commands lists the stored setup command mnemonic codes. These commands provide for saving instrument

setups and recalling them for use. A current instrument setup can be saved to internal setup memory using the SSN(m) command, where m = memory locations 1 to 9. Up to nine instrument setups can be stored in this manner. The command RSN(m) recalls a stored instrument setup from internal setup memory locations 1 to 9.

If more than nine instrument setups are needed, or if it is desirable to store the setups in the controller instead of the CW generator memory, the MG362x1A can be commanded to output and accept stored setups over the bus.

The SAF command outputs the current instrument setup to the controller in a 4100-byte (approximately) binary data string. The controller stores the instrument setup. The RCF command readies the CW generator to receive a new instrument setup recalled from the controller.