RE: Four channel tone filter radio
The casing is "under construction".
Wood, birch plywood.
A second layer of plywood will be attached to the visible to create enough rigidity, so totall thickness will be 6 mm/ 1/4 inch.
Inside I'll mount brass shielding on the "walls".
The dimensions are based on minimum content for the electronics, the circuit board, 3 sticks and on/off switch and to supply, two dummy B1643 90 V battery's and (dummy) 2 D mono cells of 1.5 V.
Sticks will be mounted on front of the casing and the entrance on the backside.
TF