Why not just use a transformer from 6VAC to 12VAD?Max,
Actually the supply is a conversion of 6 Volt AC to 16 Volt DC. This DC needs to be inverted to 12 Volt AC.
That's what I would do. Just use a common transformer with a 12 VAC center tapped ( 6 - 0 - 6 ) secondary set up as a autotransformer to get the 12 VAC directly from the 6 VAC source.Why not just use a transformer from 6VAC to 12VAD?