In Mr. Gameswat's post of 30/8/15 he expressed an interest in the whereabouts of the Nic Costa 3 Ball Reserve with shocker. I am pleased to say that I now own this machine. The patent number supplied by Costa/Christies is incorrect. Whilst faded, with the aid of a magnifying glass I could read it as follows: Brevet (French for patent) 453788/13... under which is 453789/13... under which is Brit. patent 29915/13... under which is Made in Saxony.
The British patent is the same as the first French patent, i.e. Rudolf Walther at 33 Rue de Chabrol, Paris. This refers to the method of storing and releasing balls (pallet wheel). The second French patent is the same as a British patent no.GB191329916, again R. Walther, but refers to something rather different but with a similar component. Both these Brit. patents can be viewed in the patents section in the archive section of this site.
When I got the machine the shock function was on free play, not requiring a coin or a win. The wiring appeared to be vintage as it was cloth covered single core. Whilst wanting it to be true to the original specification I found it difficult to believe the shock feature would be this way so I asked a few people for advice but nobody could come up with a definitive answer and I couldn't find any internal images of this type.*
My understanding is that a stand alone shocker would have a clockwork timer at the coin entry point but there was no evidence of one on this machine so I set about revamping the wiring, keeping the existing wiring and adding a couple more wires. I used the winning ball lever as a switch.
In using the win ball lever as a switch, when the ball falls into the win tube and rests on the lever, the shocker knob is turned and you get your shock (should you want such therapy). Then turn the win knob and your token is delivered together with a free ball and any balls in the reserve. This seemed to be better game play to me. Whilst these have a reputation for being generous, because of the gallery layout once you have filled the reserve section you can the play many coins before you land in the win. As regard the flap, with the automatic feed in place I think it is very unlikely that you would be in a position where you could fire a ball before taking your token as the free ball is released at the same time as the token is delivered and the reserve ball(s) will still be held. My, my - don't I go on! Here endeth this thesis, photos hopefully to follow after I've had a lie down.
Photos of 3 Ball Reserve with shock function: