The value of these resistors depends on their gain. Using high-gain transistors such as the BD136, BD138, or another, you can use a 1 kΩ resistor. For transistors with less gain, e.g., the TIP32 or TIP42, you’ll need 220 Ω resistors.
All the transistors need heat sinks. The circuit has the same control logic as one shown for MEC125E.
Figure 1 : combined bipolar + power MOSFET.
See other circuits like this in this section of the site.
