Radio Shack 22-812A, Manual

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MASTER BKGRD 6-26-07
Taking Measurements
MASTER BKGRD 6-26-07
Measuring Frequency/Duty Cycle/Pulse Width
The meter can measure fre�uency from 10 Hz to 4 MHz and duty cycle and pulse
width with a signal fre�uency from 10 Hz to 100 kHz. The amplitude of the signal
should not be larger than 10V peak.
1. Rotate the function dial to
LOGIC/Hz and press SELECT until Hz , KHz , or
MHz appears.
Otherwise, press Hz / DUTY / WIDTH to select duty cycle function ( function ( % appears)
or pulse width function (µ pulse width function (µµ S or mS appears).
2. if you are measuring frequency, press RANGE if necessary to select manual
range then press RANGE until the range you want appears.
3. Connect the black test lead to a ground reference for the signal, and connect
the red test lead to the signal source.
Measuring AC Voltage/AC Current Frequency
The meter can measure the frequency of an AC �oltage, with or without a DC
source bias.
WARNING : To a�oid electrical shock and damage to the meter, ne�er try to
measure a fre�uency of more than 1 kHz between AC 40 volts RMS and 750 volts
RMS.
1. if you are measuring AC �oltage with a DC source bias, set the function dial to
dBm / V . Otherwise, set the function dial to ºC/ºF / V .
To measure AC current frequency, rotate the function dial to rotate the function dial to / µA/A for
0.4/4mA and 4/10A ranges or / mA/A for 40/400mA and 4/10A ranges.
2. To select the frequency function, press Hz / DUTY / WIDTH until Hz , kHz , or
MHz appears.
3. To select the duty cycle or pulse width function, press Hz / DUTY / WIDTH until
% appears (to select duty cycle) or until µS or mS appears (to select pulse
width).
4. if %, µS, or mS appears and you want to select the frequency function again,
press Hz / DUTY / WIDTH until Hz , kHz , or MHz appears.
5. Connect the test leads to the de�ice you want to check.