Kenwood CS-5130 User Manual

11. FREQUENCY MEASUREMENTS
Frequency measurements are made by measuring the peri-
od of one cycle of waveform and taking the reciprocal of
this time value as the frequency.
Procedure:
1. Following the proceudre described in section 5 "Time
Measurements", measure the time of each cycle. The
figure obtained in the signal period.
2. The frequency is the reciprocal of the period measured.
Using the formula:
Freq -
per
j
oc
|
1 cycle = 40 /*s (5 /*s/divx8 div)
[EXAMPLE]
A period of 40 /ts is observed and measured. (See Fig. 38)
Assuming that SWEEP TIME/DIV indicates 5 jis/div,
substituting the given Value:
Freq = 1/[40x 10-6] = 2.5x10
4
= 25 kHz
While the above method relies on the measurement direct-
ly of the period of one cycle, the frequency may also be
measured by counting the number of cycles present in a
given time period.
1. Apply the signal to the INPUT jack. Set the vertical MODE
to the channel to be used and adjusting the various con-
trols for a normal display. Set the VARIABLE control to
CAL position.
2. Count the number of cycles of waveform between a
chosen set of graticules in the vertical axis direction.
Using the horizontal distance between the vertical lines
used above and the SWEEP TIME/DIV, the time span may
be calculated. Multiply the reciprocal of this value by the
number of cycles present in the given time span. If "x 10
MAG" is used multiply this further by 10.
Note that errors will occur for displays having only a few
cycles.
Count cycles between this portion
[EXAMPLE]
For the example, within 7 divisions there are 10 cycles.
The SWEEP TIME/DIV is 5 jis/div. (See Fig. 39)
Substituting the given value:
10
Freq=
7 (div) x 5 (/iS/div)
= 285.7 kHz
Cursor measurement (CS-5130 only)
1. Apply the signal to INPUT jack, setting the vertical MODE
switch to the channel to be used and adjusting the vari-
ous controls for a normal display.
VOLTS/DIV and SWEEP TIME/DIV to obtain an easily ob-
served 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 to be
measured, and the A cursor to the right.
4. Measured value is displayed in the upper part on the
screen posterior to MAT.
29
Using the formula:
# of cycles x " x 10 MAG" value
Freq= —
Horizontal distance (div) x SWEEP TIME/DIV setting
Fig. 39
Fig. 38

Kenwood CS-5130 Specifications

General

Brand	Kenwood
Model	CS-5130
Category	Test Equipment
Language	English