gres
Full Member level 4
Constructions is a old staff. First I made project of amplifier. It should be device for hard, neverfalling, that could work in difficult situations, with power about 200W per channel for 4ohms. Project is based on typical examples of similar projects, and has been recalculated and designed for primary assumptions. It should work stable, elements are chosen with some reserve. It consist possibility to work with wide range of voltages and different load. Based on this project you can design amplifiers even with 300W – you need to change power and amount of power transistors.
Casing I have bought occasionally. Firstly it was a casing for ventilator. That’s why I need to add top board ( originally it was the same as bottom – perforated)
Transformer.
That was hard. Because I had a toroidal transformer bu 1x24V. Power – more than 1kW ( I have no possibility to check, but I quess because core was large) so I need to unwind the secondary winding, and recalculate transmission and wind again with 2,1mm wire. Block of rectifier ( condensers and bridge) I need to exchange – condensers with bigger capacity.
Device consist a canon slot that allow to plug controlling board for power amp.
Power transistors:
Are KD502 ( two pairs per channel) that are fit on radiators. Radiators consist temperature sensor.
Front and rear board.
i made them so can fit into casing.
Parameters – for sin 1KHz and 4 ohm can reach 196W. power band from 15Hz to 30kHz and more. Bridge 35A/400V, condensers 5x4700uF/50V per branch. Power voltages – 2x46V DC.
More informations and a lot of pictures you can find at https://www.elektroda.pl/rtvforum/topic1553657.html
