31,934
edits
647: Difference between revisions
vertical interface impedance
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(vertical interface impedance) |
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The horizontal amplifier in the 647A uses selected 2N3119 NPN bipolar transistors for the output. | The horizontal amplifier in the 647A uses selected 2N3119 NPN bipolar transistors for the output. | ||
These are specified as having and Ft of 250MHz and a Vceo max of 80V. | These are specified as having and Ft of 250MHz and a Vceo max of 80V. | ||
The interface between the vertical plug-in and the indicator unit is a 93-ohm controlled-impedance | |||
connection. This is in contrast to the 500-series scopes, which appear to | |||
the plug-in as a high impedance. For example, there is a cathode follower immediately after the | |||
plug-in connector in a 547. Notable exceptions are the 585 and 585A, which interface the signal | |||
from plug-in to the scope at a 93-ohm impedance, like the the 647A. | |||
Is it the only scope to use those plug-ins? It is unusual to see only one scope in what appears to be the beginning of a series. Was it discontinued because of lack of demand? What replaced it? | Is it the only scope to use those plug-ins? It is unusual to see only one scope in what appears to be the beginning of a series. Was it discontinued because of lack of demand? What replaced it? | ||