WAVEGUIDE TESTING WITH MILLIMIf'ROSECOND PULSES 



37 



it to the normal amplifying condition for fifty millimicroseconds, during 

 which time the 128th pulse is passed on to the output of the generator 

 as shown on Fig. 1. 



The synchronizing system is also shown on Fig. 1. A 100-kc quartz 

 crystal controlled oscillator with three cathode follower outputs is the 

 basis of the system. One output goes through a seven stage multiplier 

 to get a 12.8-mc signal, which is used to control a pulser for synchroniz- 

 ing the circulating loop. Another output controls the gate pulser for the 

 output traveling wave amplifier. Accurate timing of the gate pulse is 

 obtained by adding the 12.8-mc pulses through a buffer amplifier to the 

 gate pulser. The third output synchronizes the indicator oscilloscope 

 sweep to give a steady pattern on the screen. 



Although this equipment was fairly satisfactory and served for many 



OSCILLATOR 



AND CATHODE 



FOLLOWERS 



100 KC 



I 1 



MULTIPLIER 



100 KC TO 



12.8 MC 



SYNC 



PULSER 



0.02 A SEC 



12.8 MC 



500 MC 



BANDPASS 



FILTER 



GATE 



PULSER 



0.05 USEC 



100 KC 



A 



BUFFER 

 AMPLIFIER 



"1 



CRYSTAL 

 EXPANDER 



U 



AGC I 



WAVEGUIDE 



DELAY 



LINE 



TW TUBE 



■Y^ 



MILLI/iSEC/ 

 9000 MC/' 

 PULSES 

 12.8 MC RATE 



MlLLIyUSEC 



9000 MC 



PULSES 



100 KC RATE 



GATED 

 TW TUBE 



SYNC SIGNAL TO 

 INDICATOR SCOPE 



Fig. 1 — Block diagram of the regenerative pulse generator. 



