backlit PCB layout of the TDA2040 solid-state amp i’ve been working on. i’m still using perf boards until i wrap my head around designing PCB layouts in EagleCAD. i do a lot of work in the dark.
well here’s the first draft of the simplest medium powered solid state design i could muster. TL082 can easily be substituted with a TL072 which is probably better anyhow (i just have all these TL082s laying around). the power supply i’m using more like 14-15V. both ICs should easily be able to handle up to 20V and that would allow for louder operation, but i think 15V is safe. all the resistors are 1/8W minus R20 which is 1/4W.
prototype of a 20-watt TDA2040 based amplifier that i’ve been working on. running a 12-volt power supply and it’s surprisingly loud.
the need for small and portable amplifiers has arisen mainly by a desire to come up with some sort of all-purpose busking amplifier. here is the first screen shot of the output from the preamp section. the entire amplifier is powering an Eminence Beta-12LTA off of a mere 6V. don’t ask me how. it took a while to find the right combination of resistors for the TL082 to run stable at such a low voltage. it’s also surprisingly loud being that it’s about 26V away from the recommended supply (±16V). i’ll probably be posting a schematic soon.