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useful for measuring the peak-to-peak amplitude of a signal. | useful for measuring the peak-to-peak amplitude of a signal. | ||
The mechanisms used by the digital unit are a sample and hold circuit, a comparator, a counter, and a switched tap voltage divider. | The mechanisms used by the digital unit are a sample and hold circuit, | ||
The digital unit takes its input from the vertical signal produced by the sampling unit. | a comparator, a counter, and a switched tap voltage divider. | ||
The digital unit takes its input from the vertical signal produced by the sampling unit. | |||
Therefore, it operates on a low-speed signal, | |||
somewhat similar to the intermediate frequency (IF) in a superheterodyne radio. | somewhat similar to the intermediate frequency (IF) in a superheterodyne radio. | ||
The user of the 567 positions two cursors along the X-axis. | The user of the 567 positions two cursors along the X-axis. | ||
The tapped voltage divider produces several voltages along the interval spanned by the two cursor voltages: | These cursors define two times and two voltages. | ||
10%, 20%, 27%, 50%, 73%, 80%, and 90%. | The tapped voltage divider produces several voltages | ||
along the interval spanned by the two cursor voltages: | |||
10%, 20%, 27%, 50%, 73%, 80%, and 90%. | |||
These voltages are used for making measurements such as the 10%-to-90% rise time. | |||
In this case, a counter is reset and started when the signal passes through the 10% voltage. | In this case, a counter is reset and started when the signal passes through the 10% voltage. | ||
The counter counts the number of cycles of a built-in crystal clock. | The counter counts the number of cycles of a built-in crystal clock. | ||
the counter is stopped and the count is displayed on the [[nixie tube]] digital numeric readout. | When the signal reaches the 90% voltage, | ||
digital unit are controlled by switch contacts on the timing unit plug-in, which connect to the digital unit through a multi-pin connector in the 567. | the counter is stopped and the count is displayed on the [[nixie tube]] digital numeric readout. | ||
The units and decimal place of the | |||
digital unit are controlled by switch contacts on the timing unit plug-in, | |||
which connect to the digital unit through a multi-pin connector in the 567. | |||
The 567 does not have any post-deflection acceleration of the beam. | The 567 does not have any post-deflection acceleration of the beam. |