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BELL SYSTEM TECHSICAL JOURNAL 



oscillator with indiulixc fied-back, a 223-A tube operating as a 

 speech am])lifier or modulator and a 223-A tube operating as a high 

 frequency anii)lifier. The |)latc or constant current system of modu- 

 lalinn is emploxed but dilTers somewhat from the usual practice in 



I'ig. 7 — Rear View of Trdnsmiiu-r I'diiel with C"o\tT Kcmovcd 



that the ouljiut of the high fie(|uency amplifier is modulated ralher 

 than the output of the oscillator itself. This scheme was found to 

 delixer more modulated jxiwer than the usual arrangement since it 

 is not limited to the same extent by the oxerloading of the higii fre- 

 (|uency amplifier. This circuit has a power output of one watt, which 

 has i)ro\e(l to be ample f(jr normal o|)eration (jf the carrier system. 



