[ARC5] Crystal Headphones

[Fuqua, Bill L]

  Many years ago, 50's and 60's some company made high impedance crystal headphones, not ear phone but Headphones.

They were quite sensitive. I am doing a study of headphone and earphone sensitivity and have an assortment of crystal earphones,

ceramic earphones ( including the ones used lately with crystal radio kits that are terrible) and magnetic headphones (2kOhm) and

a few odd ones.

  I have GR calibration source and fixtures and such and am ready to start.

Today, one can't make a sensitive crystal set due to poor earphones that are available. I plan to try a design of my own after I finish

the experiment modeled after the old style crystal earphone but using a ceramic cantilever bimorph and foil diaphragm.

If you have a set of crystal headphones and want to have them compared with the others, please contact me.


73

Bill wa4lav
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