Heathkit Model IM-30

Transistor Checker

Calibration Procedure

· The meter pointer should be on the center zero of the meter scale.  If the pointer is not over this mark, adjust the zero-adjust screw at the bottom of the meter until the pointer is properly aligned.

· No Current flows in the tester unless one of the four levers is moved.

· Install seven fresh D cell batteries into the unit.

* * * * * * *

VOLTAGE CHECKS

· All voltages are INT BATT settings.

· Meter will not deflect if any voltage is set at EXT positions.

Collector Voltages

(    )         Set the POLARITY switch to the PNP / DIODE REV position.

(    )*       Set the COLLECTOR VOLTAGE switch to the 1.5 position.

(    )*       Push the second lever forward to the COLLECTOR VOLTAGE position.

                Meter indication should reflect the collector voltage switch setting.

(    )*       Repeat the above step for each of the other five COLLECTOR VOLTAGE switch positions.

(    )         Set the POLARITY switch to the NPN / DIODE FWD position.

(    )         Repeat the above three marked steps*.

Leakage Voltages

(    )         Set the POLARITY switch to the PNP / DIODE REV position.

(    )*       Set the LEAK VOLTAGE switch to the 1.5 position.

(    )*       Push the third lever forward to the LEAK VOLTAGE position.

                Meter indication should reflect the leakage voltage switch setting.

(    )*       Repeat the above step for each of the other five LEAK VOLTAGE switch positions.

(    )         Set the POLARITY switch to the NPN / DIODE FWD. position.

(    )         Repeat the above three marked steps*.

* * * * * * *

BIAS CONTROL LEVER

(    )         Connect a jumper wire between the EMITTER and BASE terminals.

(    )         Set the BIAS control to maximum counter-clockwise.

(    )         Set the BIAS switch [in front of BIAS terminals at top] to the INT position.

(    )         Set the POLARITY switch to the PNP / DIODE REV position.

(    )         Set the LEAK CURRENT switch to the 15 ma position.

(    )         Set the COLLECTOR CURRENT switch to the 150 ma position.

(    )         Push and hold the first lever forward in the BASE CURRENT position.

(    )         Adjust the BIAS control clockwise.

               Meter indication should follow control setting.

(    )         Set the BIAS switch to any EXT position.

               Meter indication should return to the center zero position.

(    )         Disconnect the jumper wire between the EMITTER and BASE terminals.

* * * * * * *

COLLECTOR CURRENT LEVER

(    )         Connect a jumper wire between the COLLECTOR and EMITTER terminals.

(    )         Set the POLARITY switch to the PNP / DIODE REV position.

(    )         Set the COLLECTOR VOLTAGE switch to the 1.5 position.

(    )         Set the COLLECTOR CURRENT switch to the 15 amp position.

(    )         Pull the second lever down to the COLLECTOR CURRENT position.

               Meter indication should deflect to the right.

(    )         Set the COLLECTOR CURRENT switch to the 1.5 amp position.

(    )         Pull the second lever down to the COLLECTOR CURRENT position.

               Meter indication should deflect slightly more.

* * * * * * *

SHORT TEST LEVER

(    )         Connect a jumper wire between the COLLECTOR and EMITTER terminals.

(    )         Set the POLARITY switch to the PNP / DIODE REV position.

(    )         Set the COLLECTOR VOLTAGE switch to the 1.5 position.

(    )         Pull the third lever down to the SHORT TEST position.

               Meter indication should deflect to the right.

(    )         Disconnect the jumper wire between the COLLECTOR and EMITTER terminals.

(    )         Pull the third lever down to the SHORT TEST position.

               Meter indication should remain at the center zero position.

*******

I_CBO LEVER

(    )         Connect a jumper wire between the BASE and COLLECTOR terminals.

(    )         Set the LEAK VOLTAGE switch to the 1.5 position.

(    )         Set the LEAK CURRENT switch to the 1.5 amp position.

(    )         Pull the fourth lever down to the COLLECTOR TO BASE I_CBO position.

               Meter indication should deflect off-scale.

(    )         Disconnect the jumper wire between the BASE and COLLECTOR terminals.

* * * * * * *

GAIN HIGH-LOW SWITCH

(    )         Connect a jumper wire between the BASE and EMITTER terminals.

(    )         Set the BIAS control to maximum counter-clockwise.

(    )         Set the BIAS switch to the INT position

(    )         Set the POLARITY switch to the PNP / DIODE REV position.

(    )         Set the COLLECTOR CURRENT switch to the 15 ma position.

(    )         Set the GAIN HIGH-LOW switch [bottom right] to the LOW position.

(    )         Set the GAIN TEST control [large dial] to the 75 position on the outer scale.

(    )         Pull and hold the first lever down in the GAIN position.

(    )         Adjust the BIAS control slightly clockwise.

               Meter indication should follow control setting.

(    )         Set the GAIN HIGH-LOW switch [bottom right] to the HIGH position.

(    )         The meter indication should deflect to the left more.

(    )         Disconnect the jumper wire between the BASE and EMITTER terminals.

* * * * * * *

GAIN TEST CONTROL CALIBRATION

(    )         Connect a jumper wire between the BASE and EMITTER terminals.

(    )         Set the POLARITY switch to the PNP / DIODE REV position.

(    )         Set the BIAS control to maximum counter-clockwise.

(    )         Set the COLLECTOR VOLTAGE switch to the 1.5 position.

(    )         Set the COLLECTOR CURRENT switch to the 15 ma position.

(    )         Set the GAIN HIGH-LOW switch to the LOW position.

(    )*       Set the GAIN TEST control to the 10 position on the outer scale.

(    )*       Pull and hold the first lever down in the GAIN position.

(    )*       Adjust the BIAS control clockwise until the meter indication to the left reads 5 on the 15 scale.

(    )*       Set the GAIN TEST control to maximum counter-clockwise.

(    )*       Pull and hold the first lever down in the GAIN position.

(    )*       Adjust the GAIN TEST control clockwise until the meter indication starts to deflect.

               Note this position of the indicator.

(    )*       Loosen the GAIN TEST control knob setscrew.

(    )*       Set the knob pointer to the zero position.

(    )*       Retighten the GAIN TEST knob setscrew.

(    )         Repeat the above nine steps* until no changes is observed in the readings.

(    )         Disconnect the jumper wire between the BASE and EMITTER terminals.

* * * * * * *

(    )         Set the POLARITY switch to the TRANSIT / OFF position.

(    )         Set the COLLECTOR VOLTAGE switch to the 1.5 INT BATT position.

(    )         Set the LEAK VOLTAGE switch to the 1.5 INT BATT position.

(    )         Set the BIAS control to maximum counter-clockwise.

(    )         Set the COLLECTOR CURRENT switch to the 150 ua position.

(    )         Set the LEAK / DIODE / BASE CURRENT switch to the 150 ua position.

(    )         Set the GAIN TEST control to maximum counter-clockwise.

(    )         Set the GAIN HIGH-LOW switch [bottom right] to the LOW position.

(    )         Calibration procedure is complete.