Figure 2607 -- Duddell Moving Coil Oscilliograph

General view of electromagnet form of Duddell moving-coil oscillograph, showing the oil bath, and electromagnet.

This instrument is specially designed to have a very high natural period of vibration (about 1 / 10,000 of a second) so as to be suitable for accurate research work. It is quite accurate for frequencies up to 300 Hz.

In the figure:

• A is the brass oil bath in which two vibrators are fixed
• B, core of electromagnet which is excited by two coils
• C, one of the two coils
• D, two pairs of terminals for connecting the two coils
• E, bolts that hold the oil bath in position between the poles of the magnet
• F, two of three leveling screens (one is hidden behind the oil bath)
• G, terminals of one vibrator
• H, fuse
• K, thermometer with bulb in center of oil bath

• Hawkins Electrical Guide, Volume 6
• Chapter 63: Wave Form Measurement
• Page 1858, Figure 2607
• 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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