[WBEL-users] Installation problem...

[Andy Rabagliati]

On Thu, 21 Apr 2005, Vic wrote:

> Years ago, while working with Sparcs, I came up with a simple rule :
> 
> "If at first you don't succeed, rip the piggin' terminator off."

Sending high speed signals over wires requires a standard impedance,
equivalent to an infinite length of the line.

This is so that when the signal gets to the other end, it is fully
absorbed, and is not reflected back to cause interference with later
signals. This is usually of the order or 50 - 100 ohms.

SCSI can be daisy-chained.

The drive in the middle must therefore present a high-impedance on the
line, and the drive at the end must provide termination.

Alternatively, all drives must present high-impedance, and the end of
the line should have a terminator attached.

Often the drive itself has a jumper, terminate or not ?

My guess is that before you "ripped the piggin' terminator off", both
the drive and the terminator were set to provide termination.

Cheers,    Andy!