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TABLE 5.-Pass Band-width at Designated Levels below Pass Maximum

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(a) (b) Sending and receiving band filters, 425 cycle.-Voice frequency carrier telegraph system for cables, Hamilton Nyquist, Long & Phelps, A. I. E. E., March 1925.

(c) (a) and (b) combined.

(d) (e) Sending and receiving band filters, 1,105 cycle.

(g) and (h) combined.

(j) Band-pass filter, 4.06 to 6.83 kc.-Carrier telephone system for short toll circuits, Black, Almquist & Ilgenfritz, Trans. A. I. E. E. January 1929.

(k) 1,200 cycle, low-pass filter.

(1) 3,000 cycle, low-pass filter.-Carrier systems on long-distance telephone line, Affel, Demarest & Green, A. I. E. E., June 1928. (m) 3,300 cycle, low-pass filter.-Black, Almquist & Ilgenfritz.

(n) 3,300 cycle high-pass filter.-Black, Almquist & Ilgenfritz.

(d) and (e) combined.

(h) Sending and receiving band filters, 1,735 cycle.

For convenience in interpreting the attached curves in terms of either voltage current or power ratios, the following table gives the ratios which correspond to a series of values of the transmission unit in decibels. ratios are shown in Fig. 9.1

These

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