Homer Menu

The Homer menu primarily groups functions related to the Homer Analyzer.

Run-Pause

Clicking the Run-Pause menu item or the equivalent button has two effects:

  • A command is issued to the Homer to start repeated measurements, possibly autotuning, and sending results.

  • The PC starts monitoring the Homer, i.e., receiving data messages, processing them, and displaying measurement results either as numbers or graphs or both.

The button appearance changes to the Pause symbol .

Clicking the menu item or the button again does not stop Homer internal activity, it only stops monitoring in the sense that the PC ignores data coming from the Homer. The effect may be immediate or delayed until the current sweep completion, depending on the status of the Homer|Finish Sweep menu item (see details in How to Start and Stop Sweeping).

Stop Homer

Clicking the Stop Homer menu item or the equivalent toolbar button has two effects:

  • A command is issued to the Homer to go idle, i.e., to stop making internal measurements, autotuning, and sending data. The Homer then just waits for further commands.

  • Homer monitoring is discontinued.

The effect is immediate. For details, see How to Start and Stop Sweeping.

Finish Sweep

Checking or unchecking the Finish Sweep menu item controls the instant the monitoring is actually discontinued after clicking the button or the Spacebar (provided main window has focus) or F9 or the Run-Pause menu item while sweeping (monitoring the Homer).

  • If Finish Sweep is unchecked, the monitoring stops immediately (in the middle of the sweep).

  • If Finish Sweep is checked, the monitoring continues until the current sweep is completed (graphic traces reach the end of the plots), then it stops.

Sampling Setup

Opens the Homer Sampling Setup window to select the data sampling and processing mode (Waveform) and define the corresponding sampling and triggering parameters as well as the frequency counting time.

An alternative method for opening this window is the shortcut Ctrl+Q.

TX Timing

Opens the TX Timing Window to define the cadence with which the measurement results will be updated and transmitted via the communication interface.

Points per Sweep

The Points per Sweep menu item (or the corresponding  Pts  toolbar button or the Ctrl+N shortcut) defines the count of measurement points displayed on the x-axis of rectangular plots (sweep size). At the same time, Points per Sweep is the number of data points used in Save Results operations.

Plane Ext

Any reflection coefficient must be defined at a certain cross-sectional plane along the transmission line. Load reflection coefficient GL is, by default, referenced to the output flange of the Homer. However, this reference plane can be arbitrarily shifted by the user by means of the Plane Ext menu item or the corresponding  Ext  button.

If the original load reference plane is at a location x0 along the transmission line and this plane is shifted to another location x1, the original (GL0) and new (GL1) reflection coefficients are related by

where x increases in the direction from the generator to load (outwards of Homer output), Dx = x1 – x0 and lg is the guide wavelength. The formula represents the rotation of GL0 by an angle proportional to the extension Dx. The rotation direction is counter-clockwise if the plane is shifted towards load (Dx > 0).

If the load reference plane is shifted, the symbol GL and its arrow in the Tuner View window are shifted from their default location shown in Fig. 38 either to the right (if extension Dx is positive) or to the left (if Dx is negative).

A reference plane shift enables you to compensate, e.g., for a section of waveguide connected between the Homer output and your applicator.

A reference plane shift does not affect autotuning, for which the input reflection coefficient GI is always used.

For more details about reflection coefficients measured by the Homer and their reference planes, see section Input and Load Reflection Coefficients, Deembedding.

Transform

The submenu items of the Transform menu item launch actions associated with a user-defined bilinear transform of the input reflection coefficient GI. For details, see Transforming Input Reflection Coefficient section.

Counter

Since a magnetron frequency can easily change by as much as 1% (several tens of MHz at 2.45 GHz) when varying its anode voltage (and hence the output power level) or the load reflection coefficient, the Homer contains an internal counter which measures the actual frequency and interpolates the system parameters (calibration data) for more accurate measurement. The counter can be enabled and disabled by clicking the Counter menu item. When disabled, a substitute frequency Fsubst is used by the Homer. The substitute frequency value can be specified by the user (see the Substit Freq menu item below).

Frequency, along with other quantities, is displayed in the Results windows. When the Counter is OFF, the LED-like frequency indicator of the Maxi Results window turns blue. For more details, see section Results windows.

Switching the counter OFF and defining an appropriate Fsubst may prove useful in situations where the counter may provide false or unreliable data (e.g., when power is too low or pulses modulating the magnetron are too short or you wish to measure Rectified or Pulsed signals without triggering).

Count Time

Clicking Count Time or, equivalently, the  Tc  toolbar button opens a dialog to define the gating interval in microseconds of the frequency-measurement counter. Separate count times are used in CW, Rectified, and Pulsed modes of sampling. All three count times are stored in the HomSoft Ini File.

In the case of CW sampling mode, the prompt suggests the minimum count time recommended for accurate frequency measurement (quantization error below 40 ppm, i.e., 10 kHz at 2.45 GHz), although a count time ten times shorter is still satisfactory.

In the case of Rectified sampling mode, the prompt suggests the maximum recommended count time, which is 75% of the ripple half-period. This tentative suggestion assumes that the magnetron anode voltage is obtained using a half-wave single-phase rectification of the power line voltage.

The actual count time will be the highest multiple of 16 ms that does not exceed the set value.

The count times can also be set in the Homer Sampling Setup window.

Freq Toler

Clicking Freq Toler opens a dialog to define the frequency tolerance Ftoler, which is the maximum allowed deviation of the measured frequency (Fmeas) from the Homer nominal frequency Fnomin. If Fmeas falls outside of the interval bounded by

Fnomin ± Ftoler

then Fmeas is deemed invalid and will be replaced with a substitute frequency Fsubst (see the Substit Freq menu item below). If this happens, the LED-like frequency indicator of the Maxi Results window turns red (and so does the font of the Mini Results window).

Homer nominal frequency Fnomin is a fixed, intrinsic quantity for each class of Homer products. It can be found in the System Info window, page Homer, item Nominal frequency.

Substit Freq

Clicking Substit Freq opens a dialog to input a user-defined substitute frequency Fsubst. The Homer will send the substitute frequency instead of the measured frequency when at least one of the following occurs:

  • The frequency counter is disabled by Homer|Counter command.

  • The measured frequency falls outside the permitted tolerance interval (see the Freq Toler menu item). This can happen when, for instance,

  • the generator power level the is too low;

  • the generator is pulse-modulated and you do not employ triggering;

  • the internal counter is faulty (which, of course, will never happen J).

Frequency, along with other quantities, is displayed in the Results windows. When the substitute frequency is used while the Counter is ON, i.e., when Fmeas is outside of the tolerance range, then the LED-like frequency indicator of the Maxi Results window turns red. For more details, see section Results windows.

Note: If, for some reason, the user-defined substitute frequency is invalid, Homer firmware determines what will be sent as Fsubst, the last resort being the nominal frequency Fnomin.

MultiCAN

This menu item and its submenu are available only when CAN communication method is used and more than one Homer is detected on the CAN Bus. See MultiCAN: More Homers on CAN Bus.

More

The More menu includes the following items:

Suspend on Low Signal

When the warning Low Signal is reported from the Homer, e.g., after you switch off the magnetron power, the graphical display of “measurement” results may become annoyingly noisy. While the Homer continues transmitting these meaningless results, HomSoft may decide to ignore them and not update plots until the power becomes sufficiently high again. The decision is based on the status of the Suspend on Low Signal menu item:

  • If the item is checked, the sweeping is suspended until the Low Signal condition ceases.

  • If the item is unchecked, the sweeping (showing random, noisy data) continues regardless of the Low Signal status.

In either case, the message “Low Signal” appears in the left panel of the Status Bar.

Note: This setting is purely cosmetic and should not be confused with suspending autotuning when the Low Signal condition occurs.

For more details on the Low Signal condition, see Homer Error Byte.

Pow Cal Factor

Opens a dialog to set a user-defined Homer power measurement correction factor. See Power Measurement Calibration Factor.

Halt Server

Clicking the Halt Server menu item terminates the execution of Homer internal server program SrvHo.exe and starts the internal utility SrvDld.exe, enabling transfer of files between the Homer and the PC via RS232. A special Windows program (DwnLoad.exe) must be started in your PC for this. For details, see Help to DwnLoad.exe.

Note that transfer of files is normally handled by HomSoft itself so this functionality is essentially obsolete.

Restart Server (F7)

Clicking Restart Server or pressing the F7 hot key terminates and immediately restarts the Homer internal server program SrvHo.exe. This causes the Homer to reset to default settings without the need of switching its DC power OFF and ON. This function can be useful in the following situations:

  • New or edited configuration and auxiliary files have been uploaded (sent to the Homer). These include for instance:

  • Hom.cfg, Tun.cfg (the most typical operation).

  • Rs232.cfg, Can.cfg (e.g., to change the baudrate).

  • New SrvHo.exe has been uploaded (typically, upgrading Server to a newer version).

Notes:

  • To terminate SrvHo.exe and restart it in a new communication mode (RS232 vs. CAN), use the Tools| Switch Server menu.

  • Since Restart Server causes discrepancy between the settings of the Homer unit and those of HomSoft, you should always restart HomSoft after a Restart Server action.

DAQ Setup

This menu item opens a window that collects, in concise form, some of the more advanced Homer settings, regarding primarily the measurement of detector voltages as well as measurement timings. You will need it very rarely. For details, please refer to the Data Acquisition Setup Window topic.