Uncle Jaque,

I can't give you any technical information, but I can put you on to a good resource site. The House of Musical Traditions has a good website, an excellent store, and they sell, repair, and can give advice on these instruments. I'm pretty sure the web address is hmtrad.com If you have any trouble with that address, just type the name of the store into a search engine. (Sometimes I don't trust my memory for web addresses.)

Good luck and best wishes,

Carol