RCA Master Reference Book for Disc Recording

On Mon, 16 Nov 2009, Ray A. Rayburn wrote:

I have posted a never before seen historic book to my website.  It is the
 "Master Reference Book for Disc Recording" issued in February 1940 by the
 Recording Department, RCA Manufacturing Company, Inc. Camden, New Jersey,
 USA.  It is 386 pages in length and the file is 46.7 MB in size so please
 don't try to download it unless you have a high speed Internet connection.
 Thanks to Doug Jones for the conversion of this historic book into pdf form.
 This is the internal use only book that covers all the equipment used to
 produce sound recordings at RCA Studios worldwide as of February 1940.
only 15 copies of this book were ever made.  This copy was issued to the
studio  in Hollywood, CA, and may be the only copy left in existence.  It came into
 my possession when I worked for RCA Records in NYC and they threw it out in
 the trash.
 It contains manuals, schematics, photos and more for:
 Filters and Compensator Units
 Microphone and Re-recording Mixers
 Monitor Equipment - Meters, Loudspeakers Etc.
 Recorders, Pickups and Related Accessories
 Power Supplies
 Recording Machines
 Test Equipment
 Transmission and Schematic Diagrams
 Equipment Assembly and Inter-unit Wiring Diagrams
 Testing and Maintenance of Equipment
 Operation Standards
 Frequency Response and Performance
 Material and Dimensional Data on Recording Blanks and Records
 You can visit the download webpage which has additional information here or simply download the book here.