Hello.
I bought a Conn 8D from a family friend the spring before I started college and I absolutely do not know when it was made. I have tried using the charts to figure it out, but I am having trouble.
I would really appreciate any insight.

The serial number is on the second valve and it is 5 613625. The etching on the bell says CONN 8D USA.

Thanks so much in advance!
Amber