Ample documentation exists on the pantograph process, including various court-challenges. If you are interested in further research into the topic, you may login to the APS site at
www.antiquephono.organd navigate to Articles / Advanced
There you can enter the word
Pantograph
in the Search field
and you will see the following articles available for viewing and download, that mention the word “pantograph”.
APM-VOL V-05-1977
APM-VOL VII-03-1982
ITG-1985-11
ITG-1986-11
ITG-1990-11
ITG-1991-06
ITG-1992-04
ITG-1996-06
ITG-1997-12
ITG-1999-10
ITG-2000-03
ITG-2002-01
ITG-2002-11
ITG-2007-12
ITG-2010-10-11-L
NAG 95-2_REDACTED 1996
NAG-1982-03-REDACTED
NAG-1982-04-REDACTED
NAG-1989-02_REDACTED
TAP-2011-12
TSB-1990-11
TSB-1996-01
TSB-1996-05
TSB-1998-09
TSB-2000-01
TSB-2001-07
TSB-2002-03
TSB-2003-07
TSB-2003-11
TSB-2006-03
TSB-2006-12
TSB-2007-03
TSB-2008-12
TSB-2010-09
TTMR-1976-41
TTMR-1978-51
The first reference, APM-VOL V-05-1977 (Antique Phonograph Monthly) includes an informative article titled
“The Beginning of “Dubbed" Edison Blue Amberol Cylinders”
By
Ronald Dethlefson
With an Afterword by Peter Dilg
Another interesting reference is contained in:
NAG 95-2_redacted 1996 (New Amberola Graphic)
which references the “pantograph” process used with Viatphone discs.
The Antique Phonograph Society and donors are sponsoring the return of another Vitaphone short to the silver screen.
BEN POLLACK AND HIS PARK CENTRAL ORCHESTRA was made shortly after At the Club (1929). It features a young Benny Goodman and Jack Teagarden, and Teagarden both plays and talks. The Library of Congress has a 35mm negative of the film but a complete version of its soundtrack was unavailable. Some time back an incomplete soundtrack disc was synced up with a mangled 16mm print but that is all anyone has seen of this film in decades.
In February, there was a breakthrough. A complete soundtrack disc was found. Currently, this disc and the 35mm negative are being restored at the UCLA Film and Television Archive. APS plans to premiere this complete, stunning restoration at the Expo Banquet in August.