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BELL SYSTEM TECHNICAL JOURNAL 



Capacitance and resistance elements (C2R2) in conjunction with the non- 

 linear coil {L2) make up the output mesh. 



A complete cycle of the input wave is depicted in Fig. 2c, placed to corre- 

 spond with the B-H loop of the non-linear core shown above it in Fig. 2b. 



Fig. 2 — Low-level coil pulser. 



(a) Circuit diagram showing input tuning CiLi, non-linear coil is, output condenser 

 C2, and load resistor R^. 



(b) B-H loop of non-linear coil, with letters marking transitions between permeable 

 and saturable regions. 



(c) Sinusoidal input current wave scaled and placed to correspond with the horizontal 

 scale of Fig. 2b. 



(d) Pulsed output wave, {2 as ordinate; ii as abscissa. 



Action of the circuit is now to be followed throughout a cycle, starting with 

 the input wave at its maximum negative excursion, condenser d uncharged, 

 and the core in its lower saturation region. Here the slope of the B-H 

 loop and the corresponding dififerential permeability and inductance are 



