. The Bell System technical journal. Telecommunication; Electric engineering; Communication; Electronics; Science; Technology. CARRIER SYSTEMS ON TELEPHONE LINES 601 with three vacuum tubes is the modulator-oscillator panel of one channel. Below it is the demodulator-oscillator panel of the same channel. Below the latter and in the center of the bay is the jack mounting strip which makes it possible to disconnect, or switch for testing purposes, the various units of the complete equipment. The nmnc)uo«cr atur. Figure 23—Schematic showing principal equipment units in carrier repeater circuit de
. The Bell System technical journal. Telecommunication; Electric engineering; Communication; Electronics; Science; Technology. CARRIER SYSTEMS ON TELEPHONE LINES 601 with three vacuum tubes is the modulator-oscillator panel of one channel. Below it is the demodulator-oscillator panel of the same channel. Below the latter and in the center of the bay is the jack mounting strip which makes it possible to disconnect, or switch for testing purposes, the various units of the complete equipment. The nmnc)uo«cr atur. Figure 23—Schematic showing principal equipment units in carrier repeater circuit demodulator-oscillator panel and modulator-oscillator panel, respec- tively, are the next two panels of the second channel. The terminal strips will be seen at the top of the bays. The metal shields sur- rounding the vacuum tubes are useful for mechanical protection only. The testing and power distribution equipment is located in the left- hand bay. The pilot channel apparatus at the terminal station, which is employed in regulating the performance of the system to compensate for variations in the line equivalents, is assembled in a typical installation as shown in Figure 22. This apparatus may be located adjacent to the carrier terminal apparatus. The upper panel is the indicator unit with the indicator meter shown in the upper center of the panel. The panel immediately below this is the alarm panel with its voltmeter relay. On both of these panels the associated vacuum tubes are mounted in the rear. The lowest panel is the oscillator panel with its vacuum tube and frequency control. Typical Repeater Station Installations. The equipment at each carrier repeater station consists mainly of the units indicated in Figure 23. It is seen from this figure that the principal items are the line filter equipment, the amplifiers, the equalizers, the directional filters, and the jacks provided for testing and patching the equipment. Pilot channel equipment, power supply equipment, and te
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Keywords: ., bookcentury1900, bookdecade1920, booksubjecttechnology, bookyear1
