Mark writes:
>      I need to locate an adapter that takes both speakers of a head set =
> jack and combines them in to a single "mono" out put for a head set. I =
> need this for a person who can only hear in one ear. Any help would be =
> appreciated.

	This sounds very simple at first but don't go too fast.
A lot of Y adaptors just connect the left and right channels
together which is okay if you are feeding one output to two
inputs but if you connect the left and right channels together
from a pair of amplifiers, each channel will see the other
channel as a rather heavy load. if there are different signals
on the two channels. What you are actually wanting is a
two-channel passive mixer which would combine the two outputs in
to one.

	You can do this by connecting a series resistor from
each channel to a single junction which will be the hot side of
the mono headphone.

	The value of the resistors should be aproximately that
of each headphone. When you connect the resistors together, the
output level will be down about 3 DB so one may need to turn the
volume up a bit, but the series resistors will protect each
amplifier output stage from being melted by unusual loads.

Martin McCormick WB5AGZ  Stillwater, OK 
Systems Engineer
OSU Information Technology Department Telecommunications Services Group