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7704: Difference between revisions
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An optional component, the P7001 Processing Unit, can be added to a 7704A between the | An optional component, the P7001 Processing Unit, can be added to a 7704A between the | ||
acquisition unit and the display unit. The P7001 | acquisition unit and the display unit. The P7001 has a backplane with an asynchronous | ||
display electronics. Early versions of the P7001 use core memory. Later versions | bus and several cards that plug into that bus: sampler, analog to digital converter, | ||
memory, and display electronics. Early versions of the P7001 use core memory. Later versions | |||
use semiconductor RAM. The P7001 assumes a repeating input signal and | use semiconductor RAM. The P7001 assumes a repeating input signal and | ||
periodically samples the horizontal and vertical | periodically samples the horizontal and vertical | ||
signals simultaneously. This allows it to fill the memory with data points represented | signals simultaneously. This allows it to fill the memory with data points represented | ||
as coordinate pairs, (x1,y1), (x2,y2), (x3,y3), etc. It is not necessary that x2 be greater | as coordinate pairs, (x1,y1), (x2,y2), (x3,y3), etc. It is not necessary that x2 be greater | ||
than x1. The P7001 has its own power supply, independent from the 7704A. | than x1. The signal enters a fast sample and hold circuit where it is sampled at 150Ksamp/sec. | ||
Each sample is digitized using a successive-approximation scheme. The analog to digital | |||
converter is made of several chips: a digital to analog converter, a comparator, and control | |||
logic. The P7001 has its own power supply built into it, independent from the power supply | |||
in the acquisition unit of the 7704A. The bus is used for low speed signals. High speed | |||
signals are sent through coaxial cables that connect to the cards using Peltola connectors. | |||
<gallery> | <gallery> | ||