Hi,
clean the circuit with vinegar and a teethbrush !
Make it dry.
Then use a second time vinegar
make it dry again
wait 2/3 hours
use an electronic contact cleaned spray and a teethbrush !
Repeate it a 2nd time too.
Take a microscope and check it.
It you have socketed I.C. such as kickrom and many more, use also an electronic contact cleaned spray and a teethbrush ! on them and on theirs sockets too !
