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TB024  Backpanel Cable connectors on HY-II/SNA Rear Panel
 
                J.D.S. MicroProcessing Technical Bulletin
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Date Written: 10/11/89                   Submitted by:  Jim Beaky  
    Sequence: 1 of 1                           FileID: tb024
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            Backpanel Cable connectors on HY-II/SNA Rear Panel  
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 When HYDRA Version 9 units or HYDRA SNA units with the separate rear
connector panel are shipped to customers, it is IMPERATIVE that all
ribbon cables from the rear panel be connected to the HYDRA chassis.

In the case of HYDRA SNA, DSR is not terminated via connection to the
rear connector panel. This manifests itself in line ringing conditions
that produce several errors in the LOG DIAGNOSTICS along with very
slow performance of the unit itself.  In our test lab, the errors that
appeared were 3800 and 0845.

In the case of HYDRA II Version 9 unit, line noise will be the most
noticeable problem.  Because of the way DSR is handled by HYDRA II,
the problems will not be as severe as they are with HYDRA SNA, but you
will notice performance problems.