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B. Displaying Experimental Data The folder, 1fnMW, is the microwave spectrum of 1-fluoronaphthalene taken with at course resolution of 0.5 MHz/point. Start jb95.exe and open the working directory file,1fnMW.wkf. The experimental spectrum will be displayed starting at 12,000 MHz and ending at 20,000 MHz. Select the ANALYSIS dialog from the MAIN MENU. The filename 1fnMW_Scan2+1will appear in channel 1 with display status (DSP STAT) checked. There are three different levels of view: LOW, MED and RAW. The page values for LOW and MED are user adjustable and determine the number of screen pages of data that are viewable upon expanding and contracting (zoom-in and zoom-out) between the different levels of view. TYPE determines whether the data for that view is averaged (AVE) or the maximum value (MAX) is found across each interval. You must click in the TYPE box after scrolling to a new selection to make it active. The page value for the LOW resolution view is usually set at 1.0 so that all of the experimental data is displayed. Following an OK exit from the dialog, two files are created and written having JBI and JBO extensions. These files correspond to the MED and LOW resolution views, respectively. These files will be read and not created the next time the folder is accessed. Changing page values (by clicking in the edit box) or clicking in the TYPE box will cause these files to be recreated upon OK exit from the ANALYSIS dialog. The program does not remember the TYPE of averaging done so if jb95.exe is restarted and the page values are changed, be sure to reset the desired TYPE parameters. The creation time and date of the JBI and JBO files are also checked against that of the raw data file. If the JBI and/or JBO files are older than the rawdata file, they are recreated (so make sure your system clock is set properly). Also when viewing multiple channels, the JBI and JBO file lengths will be checked against those of the active channel for length consistency. The simultaneous display of channels where large length differences exist is not supported and prevented. The Status Bar of the main window will indicate the actions taken following an OK exit from the ANALYSIS dialog. Expanding the horizontal axis beyond actual size of the file is not possible at this time. This limitation also exists for the LOW and MED resolution views. For a scalar of 1.0 and offset of 0.0, the full vertical display will range from 0.0 to 10.0. Click the DIG STAT (for digital display) if a one-to-one correspondence is desired (full range from 0 to 1). If the exact scale or offset factor is not known, the RIGHT CLICK MENU from the main window display includes an autoscaling/offsetting option. The ACTIVE CHANNEL parameter is important if more than one file is displayed. The frequency and intensity information displayed in the Status Bar of the MAIN WINDOW corresponds to that of the active channel. The ANALYSIS dialog also contains parameters to set the initial absolute frequency (INIT ABS FREQ), the free spectral range (FSR) if an etalon is used for relative frequency calibration and the points per FSR (PTS/FSR). The latter two parameters determine the digital resolution at the raw data view. Of course, these parameters are valid only if the experimental data is linearized in frequency (see ASCII INPUT section). If the absolute frequency is known for a particular feature in the experimental data, enter the value in the INIT ABS FREQ and from the main window display, position the cursor cross hair on the known feature and depress the upper case "hot key" C. You will be prompted to recalibrate the INIT ABS FREQ. Be sure to set the correct FSR prior to performing this calibration procedure. Additional features in the ANALYSIS DIALOG will permit you to set the background color and the pixel width of the experimental traces. The UNITS control should be set for correct display of units along the X axis of the display. Depressing the hot key u from the MAINWINDOW display will toggle between commonly used units. The HARM (for harmonic) dialog option is useful for easily converting between harmonics using the hot key U from the display.
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