Helmet with detecting circuit mounted thereon for indicating approach to an energized powerline

Claim 1

IN COMBINATION, A HELMET TO BE PLACED UPON THE HEAD OF A WEARER HAVING MOUNTED THEREUPON A PORTABLE MULTISTAGE MINIATURIZED DETECTION CIRCUIT MEANS FOR DETECTING A RADIATED INDUCTIVE FIELD AND GIVING A WARNING TO THE WEARER WHEN THE DETECTION CIRCUIT MEANS APPROACHES CLOSER THAN A VARIABLE PRE-DETERMINED DISTANCE TO AN ENERGIZED POWERLINE, THE DETECTION CIRCUIT MEANS INCLUDING AN ENERGIZING MEANS, A NORMALLY CLOSED SWITCH MEANS FOR COMPLETING THE CIRCUIT, AN ANTENNA MEANS MOUNTED ON THE HELMET AND CONNECTED TO THE CIRCUIT MENS FOR RECEIVING THE INDUCTIVE ELECTRIC FIELD INPUT SIGNAL, A HIGH IMPEDANCE AMPLIFICATION MEANS COUPLED TO THE ANTENNA MEANS TO RECEIVE THE INPUT SIGNAL AND TO DIRECT THE INPUT SIGNAL TO A GAIN CONTROL STAGE HAVING MANUALLY ADJUSTABLE MEANS FOR SETTING A PRE-DETERMINED SIGNAL LEVEL, AUDIO-AMPLIFICATION MEANS CAPACITIVELY COUPLED TO THE GAIN CONTROL STAGE TO RAISE THE INPUT SIGNAL TO A PRE-DETERMINED VOLTAGE VALUE, RECTIFYING MEANS CONNECTED TO THE OUTPUT OF THE AUDIOAMPLIFICATION MEANS TO CONVERT THE INPUT SIGNAL VOLTAGE TO A D.C. SIGNAL VOLTAGE, SWITCHING MEANS COUPLED TO THE RECTIFYING MEANS AND OPERATIVE IN RESPONSE TO A PRE-DETERMIONED VOLTAGE VALUE THEREFROM, AN OSCILLATING MEANS CONTROLLED BY THE SWITCHING MEANS ADAPTED TO OPERATE AT SUCH TIMES AS A PRE-DETERMINED VOLTAGE VALUE IS RECEIVED BY THE SWITCHING MEANS FROM THE RECTIFYING MEANS, AUDIBLE SIGNAL MEANS MOUNTED ON THE HELMET AND CONNECTED TO THE OSCILLATING MEANS SO AS TO TRANSMIT AN AUDIBLE SIGNAL TO THE WEARER RESPONSIVE TO THE SETTING TO THE GAIN CONTROL ADJUSTABLE MEANS.