. Elements of acoustical engineering. Electro-acoustics; Sound. 178 MICROPHONES parallel rigid plate. The electrical circuit of this microphone is shown in Fig. The capacity, in statfarads, at any instant is given by Ce = Ceo + Cei sin co/ where Ceo = capacity in the absence of an applied pressure, in statfarads, Cei = maximum change in the capacity due to the external applied sinusoidal pressure, in statfarads, CO = 271/, and / = frequency, in cycles per second. SCREEN DIAPHRAGM. -CLAMPING RING CROSS-SECTIONAL VIEW -50 0 0 CIRCUIT DIAGRAM B .- » BACK 1^ PLATE 2-60 0 V V ⢠~- â ^''
. Elements of acoustical engineering. Electro-acoustics; Sound. 178 MICROPHONES parallel rigid plate. The electrical circuit of this microphone is shown in Fig. The capacity, in statfarads, at any instant is given by Ce = Ceo + Cei sin co/ where Ceo = capacity in the absence of an applied pressure, in statfarads, Cei = maximum change in the capacity due to the external applied sinusoidal pressure, in statfarads, CO = 271/, and / = frequency, in cycles per second. SCREEN DIAPHRAGM. -CLAMPING RING CROSS-SECTIONAL VIEW -50 0 0 CIRCUIT DIAGRAM B .- » BACK 1^ PLATE 2-60 0 V V ⢠~- â ^'' A â ^ r ~l u (Z -70 1000 FREQUENCY Fig. Cross-sectional view of a condenser microphone. The electrical circuit shows the microphone connected to a vacuum tube. The graph shows the open circuit voltage re- sponse frequency characteristics. B. Response in free space. A. Response for constant sound pressure on the diaphragm. From the electrical circuit eo â VEt Ce *j dt where eo = polarizing voltage, in statvolts, rE = resistance of the bias resistor, in statohms, t = current, in statamperes, and / = time, in seconds. Equation assumes that the bias resistor Teb and the input impedance of the vacuum tube is very large compared with r^. Then ^o may be con- sidered to be in series with Ceo and r^. Substituting the value of Ce from equation in equation and differentiating di (Ceo + Cei sin c>:t)rE â + (1 + VeCeio^ cos oit)i â eoCsi^ cos co/ = 0 at. Please note that these images are extracted from scanned page images that may have been digitally enhanced for readability - coloration and appearance of these illustrations may not perfectly resemble the original Olson, Harry Ferdinand, 1901-. New York, D. Van Nostrand company, inc.
Size: 1429px × 1749px
Photo credit: © Paul Fearn / Alamy / Afripics
License: Licensed
Model Released: No
Keywords: ., bookcentury1900, bookcollectionameri, bookcollectionbiodiversity
