Simple AC PSU for a rareish keyboard.

[Sebzy]

Have an old Miracle Piano minus the PSU so I'm going to make one up.
http://en.wikipedia.org/wiki/Miracle_Piano_Teaching_System
Apparently it's 12VAC@1A but I'm reluctant to just plug it directly into a transformer. What could I do to put a bit of protection into the circuit?

A simple schematic would be fantastic.

[c4757p]

1.5A fuse.

[Sebzy]

1.5A fuse.

LOL yea thought somebody would say that
Looking for something along the lines of a MOV (Metal-oxide varistor) solution.

 

[c4757p]

Er... then a MOV. Sounds like you already know what you need.

[Sebzy]

Just to be clear I'm asking for advice on how to implement protection into an AC-AC power supply to be used audio equipment.

I have looked at using a MOV but there seems to be quite a few different ways of using them and my knowledge on protection is not extensive so I'm throwing this out to the EEVBlog community asking for help in finding a finding a solution.

The solution may be as simple as just using one MOV across the primary of the transformer or several as seen in the image attached. Basically I want to know what my options are.

[SeanB]

12 VAC MOV and a 1.5A thermal circuit breaker. MOV starts to conduct at around 20V peak and will trip the breaker in under 5 seconds. All this on secondary

Mains rated MOV on mains input. Place a fuse there as well, slow blow.