[78-L] pallophotophone / times union

[Michael Shoshani]

On Mon, 2010-06-21 at 11:39 -0700, Michael Biel wrote:
> From: Vincent Fitzpatrick <jvftzjvftz at gmail.com>
> 
> > At least some of those were acoustic--of Warren Harding and Calvin Coolidge--correct?
> 
> Harding wasn't recorded but your statement that the original films were
> recorded acoustically has set me thinking. If I remember how what became
> the "Light Ray" microphone that Brunswick used worked, there was a cone
> diaphragm with a mirror at the back of the tip which vibrated with the
> sound and varied the light it reflected onto a photocell.  This would
> make it an electrical source for the recording.  

Here's a very nice description of the Pallophotophone as applied to
radio broadcasting, from a 1922 magazine, including a photograph which
does show a small horn:

http://books.google.com/books?id=vd7mAAAAMAAJ&pg=RA2-PA58&lpg=RA2-PA58&dq=pallophotophone+hoxie&source=bl&ots=bgvReKC89j&sig=1SQcVVX9MvhMI_zPPZwlFmtUHu0&hl=en&ei=lrkfTIPIBdSfnwfv54WNDg&sa=X&oi=book_result&ct=result&resnum=10&ved=0CDsQ6AEwCTge#v=onepage&q=pallophotophone%20hoxie&f=false

I've read elsewhere that once RCA and AT&T cross-licensed each other in
1926, Dr. Hoxie was able to incorporate microphones and amplifiers into
the system and make it all-electric. Not sure that would have been true,
though, or why it would have taken until 1926 when Case was recording
electrically onto film in 1923, and Tri-Ergon in...1919, I believe.