Mini Power Amplifier 30W

Many times we needed a small power amplifier, but good quality, made from distinguishable components. The design does not have any innovation. In the power stage exist a pair of transistors Darlington in package TOP3, which can screwing on a heatsink, putting between them and in the heatsink, suitable leaves mica and silicone ointment on better temperature kidnapping. The bias current regulation becomes with the TR1, as follows. We place in terminally one from resistors R20 or their R21 multimeter binding post, in scale 200mV and we regulate late the TR1 until we take clue 12mV. This voltage dip (fall) corresponds in current 30mA. We thinly leave the amplifier in this regulation for 15 min. without signal in the input and check again. If it need we correct the regulation in 30mA.

Fig.2--Power amp. 30W PCB [Top side]

Fig.3--Power amp. 30W PCB [Bottom side]