BDT61 Bipolar Transistor

• Type: NPN
• Collector-Emitter Voltage, max: 60 V
• Collector-Base Voltage, max: 60 V
• Emitter-Base Voltage, max: 5 V
• Collector Current − Continuous, max: 4 A
• Collector Dissipation: 50 W
• DC Current Gain (h_fe): 750
• Operating and Storage Junction Temperature Range: -65 to +150 °C
• Package: TO-220

Here is an image showing the pin diagram of this transistor.The complementary PNP transistor to the BDT61 is the BDT60.You can replace the BDT61 with the 2N6043, 2N6043G, 2N6044, 2N6044G, 2N6045, 2N6045G, 2N6387, 2N6387G, 2N6388, 2N6388G, 2N6530, 2N6532, 2SC3145, 2SD1190, 2SD1191, 2SD1192, 2SD1195, 2SD1196, 2SD1276, 2SD1276-P, 2SD1276-Q, 2SD1276A, 2SD1276A-P, 2SD1276A-Q, 2SD1277, 2SD1277-P, 2SD1277-Q, 2SD1277A, 2SD1277A-P, 2SD1277A-Q, 2SD1414, 2SD1415, 2SD1415A, 2SD1825, 2SD1826, 2SD1827, 2SD1829, 2SD1830, 2SD1891, 2SD1891-P, 2SD1891-Q, 2SD1892, 2SD1892-P, 2SD1892-Q, 2SD2241, 2SD2495, 2SD2495-O, 2SD2495-P, 2SD2495-Y, 2SD560, 2SD560-KB, 2SD560-LB, 2SD560-MB, 2SD633, 2SD634, 2SD635, 2SD837, 2SD837-P, 2SD837-Q, 2SD837-R, 2SD837A, 2SD837A-P, 2SD837A-Q, 2SD837A-R, BD645, BD647, BD649, BD651, BD897, BD897A, BD899, BD899A, BD901, BDT61A, BDT61B, BDT61C, BDT63, BDT63A, BDT63B, BDT63C, BDT65, BDT65A, BDT65B, BDT65C, BDW23A, BDW23B, BDW23C, BDW40, BDW41, BDW41G, BDW42, BDW42G, BDW43, BDW53A, BDW53B, BDW53C, BDW53D, BDW63A, BDW63B, BDW63C, BDW63D, BDW73A, BDW73B, BDW73C, BDW73D, BDW93A, BDW93B, BDW93C, BDW93CF, BDX33A, BDX33B, BDX33BG, BDX33C, BDX33CG, BDX33D, BDX53A, BDX53B, BDX53BG, BDX53C, BDX53CG, KSB601, KSB601-O, KSB601-R, KSB601-Y, KSD560, KSD560-O, KSD560-R, KSD560-Y, MJE800T, MJE801T, MJE802T, MJE803T, MJF122, MJF122G, MJF6388, MJF6388G, TIP100, TIP100G, TIP101, TIP101G, TIP102, TIP102G, TIP120, TIP120G, TIP121, TIP121G, TIP122, TIP122G, TIP130, TIP130G, TIP131, TIP131G, TIP132, TIP132G, TIP140T, TIP141T, TIP142T or TTD1415B.