Vintage Simmons Drums (UK) Users Group

Ok got quite a bit farther after reading some other posts.
No 15V supply - I'm amazed any of it works.
Checked back through and the transformer is at fault - 2V on the winding 
for the 15V supply.
Guessing it should be about 20V AC on the secondary to generate the 
regulated +15V supply.
Can anyone confirm that?

Cheers
Stevie