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I have an old VAXstation that has an external SCSI Bus.

When I don't have anything attached to that, I get errors. I was thinking of adding a terminator, but those that I found online are quite expensive. So I was thinking of wiring one myself.

Does anybody happen to know how I should wire them, and what resistors I need?

polemon
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1 Answers1

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All the answers and information you need are on the Wikipedia page about Parallel SCSI

It mentions that SCSI-3 requires active termination instead of passive.

It then goes on to talk about termination:

Active termination means that there is a small voltage regulator which provides a +3.3 V supply. Each signal line is then terminated by a \$110\Omega\$ resistor to the +3.3 V supply. Active termination provides a better impedance match than passive termination because most flat ribbon cables have a characteristic impedance of approximately \$110\Omega\$.

Majenko
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