A power supply for ARC-5 type receivers

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 I have been hosting a class called "Repairing your first boatanchor" over at LICW ( The Long Island CW Club) over the last 2 or three months, where I have recapped, measured and fixed an old SCR-274 BC455 40m receiver during online classes.

One issue with these receivers is powering them. Originally they were powered by dynamotors (motor generators) but these are hard to come by here in Sweden, so I wanted to design a power supply that could be used in place of the original dynamotor.

The result is seen below. Using a CD4047 as an astable multivibrator, driving a 10W pcb transformer backwards, gives us the needed ~ 200V for the receiver.


after running the receiver for close to one hour, I must say I´m pleased with how this turned out.





More details to follow.


//Tommy, SA2CLC

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