[sci.electronics] IR Headsets

kennish@janus.Berkeley.EDU (Ken A. Nishimura) (09/17/89)

I have noticed that certain symphony halls/opera houses are
outfitted with IR listening devices for the hearing impaired.
(Sennheiser comes to mind).  Does anyone know if they are
IR, or RF.  Are the similar to the Koss wireless headphones?
I am curious to know what kind of modulation they use and
the frequencies.  Will summarize and post if information forthcomes.


					-ken