Been quiet for a while.
Was running some tests on my staging yard and it was not working as I had hoped it would.
The copper wire as centre rail did not give a reliable contact to the pick up.

After considering various options I decided to give it another try.
But instead of 0.9mm wire I used 1.8mm wire now, of course this just can not be glued to the tie, but I have to screw in brass screws between the ties and then solder the wire to this. Quiet a bit more work, but the first test has been positive.
So I am now trying to finish one track so I can run more tests.
Spot the difference in the wires.