filter 39 the output of low pass filter 39 is connected to the input of bootstrap amplifier 53 the output of which is connected to voltage tuned solid state oscillator 55 the output of amplifier 35 is connected to the input of band pass filter 37 the output of which is connected to amplitude detector 41 the output of amplifier detector 41 is connected to the inputs of dc amplifier 45 and low pass filter 43 the output of low pass filter 43 is connected to one of the three inputs of speed gate doppler receiver 27 the outputs of which are connected to the inputs of recycle device 65 and launch relay 67 the outputs of recycle device 65 and launch relay 67 are connected to the inputs of coherency check device 69 the output of which is connected to the input of voltage tuned solid state oscillator 55 the output of oscillator 55 is connected to the inputs of rear mixer 29 and front mixer 61 the outputs of dc amplifier 45 are connected to the inputs of sweep generator 49 and high pass filter 47 the output of high pass filter 47 is connected to the input of pulse generator 51 the output of which is connected to the input of oscillator 55 the.