TELEPHONE RECEIVERS AND HANDSETS
Telephone receivers are electromagnetic transducers which convert telephone signals into sound pressure waves. They are made compact and of very rugged construction to withstand the abuse of telephone usage.
Figure 37.9 shows a compact version of the telephone receiver which was in use from the early 1920s until the late 1950s. Two small but very strong permanent bar magnets provide the magnetic bias field. This field is channeled to the diaphragm through the two formed soft iron pole pieces on which the coils are mounted as shown in Fig. 37.9. The whole magnetic structure is fastened to an aluminium frame which also supports the magnetic diaphragm, a perforated cover, and a dust cover membrane held in place by ...
Get Consumer Electronics now with the O’Reilly learning platform.
O’Reilly members experience books, live events, courses curated by job role, and more from O’Reilly and nearly 200 top publishers.
