Transformless amplifier

jack121 said:

Hi Thanks for reading.
I want to build a simple discrete amp with the absolutly lowest number of components possible, preferably a two stage with driver transistor and output transistor, as cheap as possible, i don't want to spend any serious money, just a few bucks.
As power supplies are expensive, do you know of any design that runs off the mains ac 240volts, just a bridge rectifier and smoothing capacitors, no transformer.
A cheap and cheerful amp for music reproduction that works and is stable, not concerned about hi-fi sound or super low distortion
Thanks

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gary350 said:

1N34 diode radio plays music and very low number of parts. NO power supply. I received 1 of these for my birthday 1958. I built 1 in electronic class 1970. Diode is 1N34. I learned just from experimenting 2 diodes in parallel music is louder. Maybe diode resistance is less with 2 in parallel??? L1 & C1 are the resonance circuit for radio frequency that you want to receive. It will only power 1 ear plug type ear phone. Antenna is a 3 ft long wire with an alligator clip on the end. When I was 8 years old I had good hearing I could hear the music play fairly loud. I'm not sure what requirements are for the ear phone. When I was in high school stores had this same type radio that picked up TV sound no video but 6 months later no more for sale. Circuit drawing shows ground but factory radio had no ground and it works.

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Here are a few bucks.

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