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use at the input fuses (F1/F2) the value which your AC-AC transformer offer - for the Yamaha PA.30 its max. 750mA - you need for F1 and F2 750-800mA fuses, 500-630mA will blow.At the output fuses you can use 500mA/630mA
normally FAST blow fuses are not good in this circuit, please use medium or slow blow fuse types !!
for the secondary fuse use a value which is 10-20% bigger than what your device ask (for example a TTSH works great with 2x 500mA fuses and should be work with a 320mA too (depends on the additional mods)
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