Hi Rolf- I have a Mayfair that does the two alternating relays (A and A1) and is otherwise the same except for no other relays in the circuit. The two handle the red and yellow bonus ladders, which alternate. https://www.ipdb.org/showpic.pl?id=1562&picno=6543&zoom=1 U (Double Target Value relay) handles that on its own.
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