Manual Waveform Determining

Preparation

  • Open and scale the standard display windows, like incident and reflected powers, or reflection coefficient magnitude.

  • Open the Results window by clicking View|Results (Maxi).

  • Open the Tuner View window (Fig. 64) by clicking the Tuner|View menu item or the Tuner button.

Fig. 64.  Tuner View window.

  • In the Tuner View window, disable autotuning (set the  AT  button to the inactive position).

  • Retract the tuning stubs by clicking the button. If your process does not permit fully retracted stubs but requires a pre-tuning instead, move the stubs to the desired positions.

  • Choose the Decimal Separator: Click the File|Separator menu item and select your preferred separator in the submenu. (Please select Point if you want to report your results to us.)

The Separator will be stored in the HomSoft Ini File so that it remains the same after a HomSoft restart.

Data Sampling

Each individual set of results that the Homer produces is a result of processing a number of samples (Sample Count Ns, up to 4095). While the Homer normally transmits only the final results, the data sampling procedure described here enables you to view and analyze each particular sample. This analysis is essential for appropriate Homer configuration. (Please note that a continuous recording of final results is called data logging.)

Make a fast, medium-speed and slow sampling as described below. The procedure is always the same; the difference is only in Homer measurement settings. The settings are summarized in Fig. 65. The parameters in parentheses cannot be modified directly; they are provided for reference only.

It is good practice to make several attempts for each sampling type, if possible, at various generator power levels.

  • Fast sampling records a 20-ms signal section with the highest sampling rate possible (200 kHz). The purpose is to identify the fastest frequency components in the power envelope detectable by the Homer. Individual samples are spaced by 5 ms sampling steps. This setting will detect any frequency components derived from the power line frequency fp (50 or 60 Hz) and its multiples, which typically reach 6 ´ fp or even 12 ´ fp.

  • Medium-speed sampling covers an interval of 200 ms with a slower sampling rate.

  • Slow sampling records a two-second span of the signal. The purpose is to discover slow reflection coefficient variations, typically caused by mechanical movements in the applicator, such as a mode stirrer rotation or objects moving on a conveyor belt.

Fig. 65.  Homer settings for data sampling.

Set Measurement Conditions

In the Homer Sampling Setup window, set the parameters according to Fig. 65 (some parameters can be set via a corresponding button shortcut).

Now, the HomSoft main window may look like that in Fig. 66 (only with empty displays).

Make Measurement

Start measurement by clicking the Homer|Run-Pause menu item or the corresponding button (the button changes to ). Note that the slow sampling process requires approximately 5 seconds to complete measurement and an additional 15 seconds to transfer all 4001 samples. Observe the progress bar on the lower toolbar.

Upon completion, the HomSoft main window may look like that in Fig. 66.

Fig. 66.  Example of HomSoft main window after sampling.

Save Results

  • Click the File|Save Results menu item or the SaveBin button, or use the Ctrl+S shortcut. A save dialog box opens.

  • Choose the file name and location, then click  Save .

  • When prompted, enter an optional comment to be saved along with the data.

Repeat

You may wish to repeat the sampling and data saving process several times or in different conditions (e.g., for various generator power levels).

Save Setup

As a useful option, save the existing HomSoft setup using the File|Save Setup menu item, the SaveStp button, or the F2 shortcut. The file name may be, for instance, FastSmpl.stp for fast sampling. Next time, instead of setting each parameter manually, you can just load the setup file (using the File|Load Setup menu item, the LoadStp button, or the F3 shortcut).

Compress and Send Files

If you need our support, complete all measurements as described above, compress (zip) the created text files and e-mail the zip file to us for analysis. (Zipping the files preserves their dates and times.)