Transistorized circuit continuity tester with lamp indicator and switch means in thecollector circuit

Claim 1

A CONTINUITY AND CAPACITOR TESTER COMPRISING IN COMBINATION A SUPPORTING SHELL INCLUDING AN INSULATING TUBE AND HAVING AN INTERIOR CAVITY; A TRANSISTOR SUPPORT MOUNTED WITHIN SAID CAVITY; A TEST PROD SUPPORTED AT ONE END OF THE CAVITY TO PROTRUDE FROM THE SUPPORTING SHELL; A BIASING CIRCUIT INCLUDING A BIAS RESISTOR SUPPORTED IN ONE END OF THE CAVITY ADJACENT THE TEST PROD ON A BIAS RESISTOR MOUNTING; SAID BIAS RESISTOR MOUNTING INCLUDING A FIBER SANDWICH INSERT HAVING A CAVITY THEREIN ADAPTED TO RECEIVE THE RESISTOR; DRY CELL MEANS MOUNTED IN THE CAVITY BETWEEN THE BIAS RESISTOR AND THE TRANSISTOR SUPPORT, THE DRY CELL MEANS HAVING FIRST AND SECOND TERMINALS OF OPPOSITE POLARITY; A PAIR OF METAL PLATES ON EITHER SIDE OF SAID FIBER SANDWICH INSERT, ONE OF WHICH IS SECURED TO THE TEST PROD END OF THE SUPPORTING CASING, THE OTHER OF WHICH IS SECURED IN THE CASING INWARDLY, THE BIAS RESISTOR BEING CONNECTED ELECTRICALLY BETWEEN THE TWO PLATES, THE OUTER PLATE BEING ELECTRICALLY CONNECTED TO AND SUPPORTING THE TEST PROD, THE INNER PLTE BEING ADAPTED TO BE ELECTRICALLY CONTACTED BY THE FIRST TERMINAL OF THE DRY CELL MEANS; A TRANSISTOR IN THE TRANSISTOR SUPPORT HAVING A COLLECTOR, A BASE AND AN EMITTER; THE EMITTER BEING CONNECTED TO THE SECOND TERMINAL OF THE DRY CELL MEANS; A CURRENT INDICATOR MOUNTED IN THE SUPPORTING SHELL, COMPRISING AN INCADESCENT LAMP AND A LAMP SOCKET MOUNTED IN THE CASING AT THE END THEREOF AWAY FROM THE TEST PROD, WITH A CENTER TERMINAL CONNECTED TO THE COLLECTOR OF THE TRANSISTOR AND A SCREW SHELL WITH A PORTION OF THE PERIPHERY THEREOF EXPOSED; A FLEXIBLE TEST LEAD HAVING AN END SECURED TO THE SUPPORTING SHELL AND ELECTRICALLY CONNECTED TO THE BASE OF THE TRANSISTOR, AND HAVING A SECOND END ADAPTED TO BE CONNECTED TO A CIRCUIT TO BE TESTED; AND A CONDUCTOR SPRING HAVING A TIP ADAPTED TO CONTACT THE EXPOSED PORTION OF THE SCREW SHELL, SAID CONDUCTOR SPRING BEING SUPPORTED AT ONE END AND ELECTRICALLY CONNECTED TO ADAPTED TO BE CONNECTED TO A CIRCUIT TO BE TESTED; AND A PRESSED AGAINST THE SECOND TERMINAL OF THE CURRENT INDICATOR FOR COMPLETING A COLLECTOR-EMITTER CIRCUIT WHEN A TEST IS TO BE MADE, SAID INSULATING TUBE BEING PROVIDED WITH AN OPENING WITH A PIN EXTENDING THERETHROUGH SECURED TO THE END OF THE CONDUCTOR SPRING FOR ENABLING THE SPRING TO BE BROUGHT INTO CONTACT WITH THE SCREW SHELL OF THE LAMP BASE BY PRESSING UPON THE SPRING FROM THE EXTERIOR OF THE SUPPORTING SHELL; THE DRY CELL MEANS BEING CONNECTED WITH SUCH POLARITY AS TO PROVIDE A FORWARD BIAS; SAID TEST PROD AND SAID TEST LEAD DEFINING A DELIBERATELY PLACED DISCONTINUITY IN THE BIASING CIRCUIT, WHEREBY THE CONNECTION OF THE TEST PROD AND THE TEST LEAD TO A CIRCUIT ELEMENT TO BE TESTED INDICATES CONTINUITY IN THE CIRCUIT ELEMENT TO BE TESTED, EVEN THOUGH IT MAY BE OF HIGH RESISTANCE, BY FLOW OF AMPLIFIER CURRENT THROUGH THE CURRENT INDICATOR AND THE PRODUCTION OF AN INDICATION OF CURRENT CONTINUITY.