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Wednesday 18 April 2018 at 17:20
The schematic shows 9.3VAC between the centre tap and the grey wires at the transformer. Those grey wires exit on the right and the total across them is 18.7VAC (9.3 + 9.3) which will be about right.
If you set your meter to resistance mode and put the meter leads across the power prongs on the AC p...
Source: http://pinside.com/pinball/forum/topic/checking-line-voltage-at-transformer-williams-sys-6-firepower#post-4346681