rickyjar
Member level 2
User “Grove82” presents his modest amplifier.
Power:
Classical work circuit TDA7294, 2 channels 2 x TDA7294 capable of working on a bridge or independently (set with valves on the PCB), this is about (knowing the possibilities of this die) 2 x 150 W or 4 x 70 W.
Preamplifier:
Based on a product of one of manufactures. Bass regulation, Treble +/-16 dB, Volume in a Mono version for each side. It was conditioned by needs.
Power supply:
A toroidal transformer 2 x 24 V 500 VA, bridge 35 A, filter capacitors about 10000 µF for each rail.
VU-meter:
A LM3915 connection with a rectifier “ideal” to LM358.
Support power supply:
A LM317T circuit supported by BD912. In this case voltage adjusted to 18 V 2,5 A. The circuit is supplied with a preamplifier, VU-meter, LED illumination, control of the fans.
Control of the fans:
Each heat sink separately, with the use of LM35 sensors. Fan speed is dependent on temperature on the heat sink.
Work progress pics and video below:
Link to original thread - Wzmacniacz by Grove82 TDA7294 2 x 150 W v 4 x 70 W