Showing a simple AM radio circuit using a TA7642 chip and the power IC amplifier circuit from the project kit manual. Added voltage stabilisation on the supply to the amp. I'm waiting for delivery of some LM386 amp chips to do away with the larger power amp chip shown here, the resulting circuit will be smaller and compact.

I'm going to play around with making my own ferrite rod by using crushed inductor coil cores and filling up the inside of an old marker pen, that has round about the correct dimensions 10cm long and 1cm diameter. Cap off the ends and it'll make a rudimentary ferrite core. Then all is needed is two coils wound around the plastic barrel. One for the antenna at around 7 turns and the other for the main tank circuit at around 70 turns.

I haven't got the correct lintz wire needed, the choices I have are very thin finely stranded insulated wire or rip apart a circuit board choke for it's fine varnished wire. I'll try both.

свернуть