For those of you unable (or unwilling) to chase down Whitlock's
JAES papers, here's a link to the pdf of a tutorial that I
presented to an IEEE EMC conference three years ago. It includes a
presentation of Whitlock's work on balanced interfaces. That
material isn't in the other pieces on my website because Whitlock
and I did several tutorial workshops together, and he presented
his own work. He wasn't able to fit the IEEE conference into his
schedule, so I did it for him. My presentation used four ppt
files. The one below is the one with Whitlock's balanced interface
work.
http://audiosystemsgroup.com/IEEE-Tutorial05.pdf
BTW -- one thing I failed to include in an earlier post is a
definition of "hybrid" bonding for balanced shielded cables, the
long standing good practice of a DC bond of the shield of a
balanced cable at one end, and a bond through a capacitor at the
other end. The Neutrik EMC XLR connector described in several of
my presentations started out life as my invention, developed and
turned into a product by Neutrik. It's essentially a
"feedthrough" for the shield, with a very low impedance to at
least 1 GHz. (I haven't seen data for how high it remains low, but
it is known to be effective in suppressing problems with 1.8 GHz
cell phones). It can be wired so that the shield has only a
capacitive termination to the shell (chassis), or with a
termination to pin 1 at DC and to the chassis above about 30 MHz.
The connector is available in both male and female versions.
73,
Jim Brown K9YC
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