Hi Greg,
You asked:
GM>just a couple questions about ArcNet..
GM>according to a sheet that came with a PureData PDI515 card
GM>i have, i can run up to 100ft of cable to a passive hub. I
GM>have a passive hub here, so thats fine for me.
GM>Now, i'll be running 3 systems for the moment, does that
GM>mean that the 4th unused port on the passive hub needs a
GM>terminator?
According to the ArcNet Cabling guide (Datapoint Publication 51087, 2nd
Edition), Model 9485 Passive Hubs are only recommended to be used on
their own and the maximum cable length between any two stations is 200
ft. By implication usused ports need termination.
Model 9490 Passive Hubs can be used with active hubs, the max cable
length between any two stations is 330 ft using RG-62 (215 ft using
RG-59U) and unused ports do not need to be terminated..
GM>Also, is it possible to use two passive hubs, or do i need to get an 
ctive
GM>hub? (in which case i'll switch to a bus-topology as its
GM>cheaper just to buy t's than it is to buy an active hub).
GM>ie:
GM>              +-------+                             +-------+
GM> Node 1 ====[=|Passive|=]==== Node 3   Node 4 ====[=|Passive|=]==== Node 5
GM> Node 2 ====[=| Hub 1 |=]=========================[=| Hub 2 |=]==== Node 6
GM>              +-------+                             +-------+
GM>where "=" is a cable, and "=]" is the bnc connector.
GM>is that possible to do? will two work together like that?
GM>will it degrade preformance?
Not permitted, passive hubs cannot be connected together.
To go beyond 4 stations at least one active hub is required.
George
 * SLMR 2.1a * KEYBOARD - Used to enter errors int a computer.
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