Three Transistor Radio Loudspeaker and Transformer

This three-transistor radio has extremely good sound quality, when you listen through a good pair of stereo headphones. The stereo jack socket feeds the same output to both driver coils in the headphones.

I had a couple of small speakers such as this and decided to use it for this project; however, it is not the best choice because when you place a piece of metal or a magnet near a ferrite rod, it usually prevents it from working. Ideally, what is required is a speaker with a plastic frame and shielded magnet.

The centre tap of the LT700 transformer is not used and I have raised its terminal up to move it out of the way. I decided not to cut it as I may wish to use it for other projects in the future.

Luckily I managed to find this modern one which is low profile and almost entirely plastic. This modern one is much louder as well and therefore worth getting, however it means spending around two bucks.

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