[Scuderia_Turini]

Well, this worked fairly easily :-) 
I used a Scalextric Sport controller. These have three-wire connectivity that includes a dynamic braking connection. My "lash-up" used a section of screw-tag connector block to join the three wires to an existing two-wire SCX controller connector and a "croc-clip".  The two-wire SCX connector plugs in as normal and the croc-clip goes on to the third pin. The braking effect works as expected.
If you only have a two-wire controller then obviously the third wire can be ignored. 

Wiring diagram is underneath, I believe that the colours are the standard for Scalextric Sport 3 wire controllers. Don't know about the two-wire versions but it is reasonably safe to wire those either way round.   

Disclaimer - I am simply showing what worked for me. Other solutions are possible. The electronics of the Chrono unit are fragile and not intended for user-servicing. It is vital to avoid mis-connecting and/or short-circuiting the wiring of the unit.

Leo

   

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