Figure 2620 - Time-index marking generator for use with Duddell moving-coil oscillograph, consisting of a large rotating light-shutter wheel and a mirror moved by a cam, to draw marker lines on moving film as the shutter wheel rotates.

• Hawkins Electrical Guide, Volume 6
• Chapter 63: Wave Form Measurement
• Page 1865, Figure 2620
• Copyright 1917 by Theo. Audel & Co.
• Printed in the United States

• Scanned by User:DMahalko, Dale Mahalko, Gilman, WI, USA -- Email: dmahalko@gmail.com
• Scanned at 600dpi, 8-bit grayscale
• Level-adjusted and cleaned up

For a list of all these illustrations used in Wikipedia please see the article Hawkins Electric Guide on the English Wikipedia.

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