I cant really comment on the op amp substitution or the resistor question
but i would not use a wire in place of the resistor. I think on the new board
you should use some IC sockets
looking at the picture with everything on it, it seems the wiring
to and from the bridge rectifier is all wrong there should only be
4 wires in total on it 2 in and 2 out, you also have 4 wires at the
input part of the board where there should only be 2
Hi all, it looks like the voltage and current pots are connected up wrong,
I could be wrong but isnt the wiper part of the pot the middle terminal ??
in your pic its connected to one of the outside terminals which has
wiper marked on the board
mate do a search for sodium persulphate its much safer than ferric chloride but there
is a downside to it thou, once it is mixed up it only lasts for a few weeks if that.
I prefer the ferric chloride as it lasts months