https://www.repairfaq.org/REPAIR/F_BC_Repair.html
Tells you where to call to get manuals and schematics as well as other tips.
If you do not want to read through it all:
Uniden America Corp.
4700 Amon Carter Blvd.
P.O. Box 95002
Fort Worth, TX 76155
(800)297-1023
In general, I find that the Mother Ship is a good place to start when hunting for relatively current product support.
Peter Wieck
Melrose Park, PA