Did you have any luck getting hold of a Siemens uniselector? It turns out that I could really do with one of these as well.....for the same reason! I have finally found the real reason that my Electrodart was scrapped.
Earlier photo attached showing the 2 (black-faced) Siemens uniselectors. This was part-way through the rewiring. The machine had been cannibalised and had much of the wiring missing/damaged. I used your wiring diagram to try to work out how it should have been wired (Thank you!). I have uploaded my revised diagrams (based on your work) to the resources section. There are some minor revisions still to come. The rewiring is just about complete now and the machine does sort of work. The biggest problem now turns out to be the Left hand uniselector......the machine runs and pays out sometimes. Mostly it pays out double or doesn't payout or pays out continuously. All the faults are a function of the faulty left hand uniselector.
The left hand uniselector has damaged wipers tips. They had been butchered and are of uneven lengths so that is currently impossible to get all the wipers to simultaneously sit somewhere near the middle of the bank contacts.
I do have a very nice 6-way (GEC?) uniselector but that needs about 50 volts and the Siemens variety (and my whole electrodart) function on 24 volts. Making the LH uniselector (alone) work from 50 volts turns out to be a real pain.
The easiest solution for me would be to replace the LH Siemens.....preferably whilst retaining the existing uniselector bank and wiring.
Hi Gary, that range of jamieson machines can be tricky buggers to set up at the best of times, I wish you luck, I am sure you will get it sorted given time, if I do manage to find any siemens uniselectors I will let you know, it is only the lower half / rotor of the selector that I need, looks like someone has had this apart and lost the lower section
I am sure one will turn up
OK. There's good news and bad news. I finally bit the bullet and rewound the 50v GEC 8 way uniselector to work from my Electrodart 24 volt system. It turns out that (for me at least) 2070 turns of 0.22mm wire can be replaced with 1040 turns of 0.31mm wire. This steps 50v down to 24v whilst keeping the power about the same (~30 watts). ie the same magnetic pulling power This was all the 0.31mm wire that would fit on the bobbin.
[Incidently an excellent primer on rewinding can be found here: http://www.qsl.net/ki7cx/Coilrewind.htm and an excellent calculator, if you want to be more technical, can be found here: http://www.daycounter.com/Calculators/C ... ator.phtml ]
That was the good news. The bad news is that I now have to unsolder all the left hand (Siemens) uniselector connections and reconnect them all to the replacement GEC uniselector......
I'm still trying to track down a SIEMENS 25 x 4 UNISELECTOR No 15A, 1950s Yes, Slotalot was trying to source one for my Dial For Money. Unfortunately, he's otherwise engaged of late and no longer has time to fix machines. so I'm going to have to get my fingers dirty (or more likely burned ) on this one. But first I have to find that uniselector...
This is currently on ebay at the moment eBay Click
GEC and Siemens are related, I can't comment on suitability especially regarding model numbers. The vendor appears to be savvy about electronicalness so maybe could advise you.
I believe the Siemens uniselectors were nominally about 24 volt whilst the GEC uniselectors were nominally about 50 volt. So they are not really interchangeable except if you take the original coil windings off and replace them with the right number of turns of the correct and different diameter coil wire. This is what I have done in desperation a couple of posts above.