Kenwood CS-8010 Instruction Manual

1 1 . FREQUENCY MEASUREMENTSFrequency measurements are made by measuring theperiod of one cycle of waveform and taking the reciprocalof this time value as the frequency.Procedure:1. Following the proceudre described in section 5 "TimeMeasurements", measure the time of each cycle. Thefigure obtained in the signal period.2. The frequency is the reciprocal of the period measured.Using the formula:F r e cl - p e n o c |1 c y c l e = 4 0 jts (5 /is/div. x 8 div.)Fig. 5 2[EXAMPLE]A period of 40 /xs is observed and measured. (See Fig. 52)Assuming that SWEEP TIME/DIV indicates 5 /ts/div,substituting the given Value:Freq=1/[40x10"6] = 2 . 5 x 1 0 * = 25 kHzWhile the above method relies on the measurement directlyof the period of one cycle, the frequency may also bemeasured by counting the number of cycles present in agiven time period.1. Apply the signal to the INPUT jack. Set the verticalMODE to the channel to be used and adjusting thevarious controls for a normal display. Set the VARIABLEcontrol to CAL position.2. Count the number of cycles of waveform between achosen set of graticules in the vertical axis direction.Using the horizontal distance between the vertical linesused above and the SWEEP TIME/DIV, the time spanmay be calculated. Multiply the reciprocal of this valueby the number of cycles present in the given time span.If " x 10 M A G " is used multiply this further by 10.Note that errors will occur for displays having only a fewcycles.Count c y c l e s b e t w e e n this portionFig. 5 3[EXAMPLE]For the example, within 7 divisions there are 10 cycles.The SWEEP TIME/DIV is 5 ps/div. (See Fig. 53)Substituting the given value:c 10Freq=7 (div) x 5 (ps/div)= 285.7 kHzCursor measurement1. Apply the signal to INPUT jack, setting the verticalMODE switch to the channel to be used and adjustingthe various controls for a normal display.VOLTS/DIV and SWEEP TIME/DIV to obtain an easilyobserved display.Set the VARIABLE to CAL.2. Set the cursor mode to MAT.3. Adjust the A REF cursor to the left of the points tobe measured, and the A cursor to the right.4. Measured value is displayed in the upper part on thescreen posterior to 11 AT.31Using the formula:# of cvcles x " x 10 M A G " valueFreq= !Horizontal distance (div) x SWEEP TIME/DIV setting