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7B92: Difference between revisions
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The 7B92 uses a discrete trigger circuit containing [[152-0177-02]] [[tunnel diodes]]. | The 7B92 uses a discrete trigger circuit containing [[152-0177-02]] [[tunnel diodes]]. | ||
The internal jumper for mainframe selection (7800/7900/7100 vs. slower) | The internal jumper (J308/J309) for mainframe selection (7800/7900/7100 vs. slower) | ||
increases the minimum holdoff time on the slower mainframe selection by adding a | increases the minimum holdoff time on the slower mainframe selection by adding a 150 pF capacitor, C307, | ||
to pin 8 of the sweep control IC, U310 ([[155-0049-00|155-0049-xx]]), in parallel to the existing capacitors. | to pin 8 (HO TIMING) of the sweep control IC, U310 ([[155-0049-00|155-0049-xx]]), in parallel to the existing capacitors. | ||
This increases the minimum pulse width of the holdoff signal on [[7000_Series_plug-in_interface|pin B4]] | This increases the minimum pulse width of the holdoff signal on [[7000_Series_plug-in_interface|pin B4]] | ||
so that the sweep logic of slower mainframes can handle it properly. | so that the sweep logic of slower mainframes can handle it properly. | ||