Gate Time; Frequency Connections; Frequency And Period Measurement Procedure From Front Panel - Keithley 3700A Series Reference Manual

Series 3700A System Switch/Multimeter Reference Manual

Gate time

The gate time is the amount of time the Series 3700A uses to sample frequency or period readings.
The gate time can be set from 0.01 to 0.273 s by setting the DMM aperture attribute.
The Series 3700A completes a reading when it receives its first positive zero-crossing after the gate
time expires. For example, for any arbitrary frequency, you may wait up to the gate time plus two
times the period of the input waveform before the Series 3700A returns a reading.

Frequency connections

Frequency connections for the Series 3700A and a switching module are shown below.

Frequency and period measurement procedure from front panel

Do not apply more than the maximum input levels for the Series 3700A or installed switching
module (whichever is lower) or instrument damage may occur.
If the Series 3700A is being controlled remotely, place the instrument in local control by pressing the
LOCAL or EXIT key.
3700AS-901-01 Rev. D/June 2018
Figure 62: FREQ and PERIOD input connections
Figure 63: FREQ and PERIOD connections (switching module)
Section 4: Basic DMM operation
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