Harlequin 48K - U47 Resistor Network

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valentin
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Harlequin 48K - U47 Resistor Network

Post by valentin »

Out of curiosity, on the Harlequin 48K (Rev. G), is there any particular reason to use a resistor network for U47 (RES x 8) and not eight 10K resistors?
Valentin
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1024MAK
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Re: Harlequin 48K - U47 Resistor Network

Post by 1024MAK »

Presumably so that these data-bus isolation resistors could easily be changed (different value) if needed. The value used depends on which range of 74 series logic chips are used.

Or speed of assembly. DIL resistor network packs are normally quicker and easier to fit compared to eight individual resistors.

But yes, from an electrical point of view, you can use eight individual resistors instead. But do make sure you have the correct value, 10kΩ sounds far too high a value. I would have expected the value to be 470Ω.

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valentin
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Re: Harlequin 48K - U47 Resistor Network

Post by valentin »

My mistake, not 10K for U47 but 470 ohms.
Valentin
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