VPR-20 front covers removed, looking from the left.

Classic Ampex construction.
Close up of the head drum. This is also a 'classic' Ampex item, and a
similar version was used in the studio VPR-2 series of machines as well.

Remember that this drum spins at 3,000 RPM, and the forces at the
circumference approach 1,000 g. This component is therefore rather
carefully balanced...

Click on the above picture to see a scanner assembly and an AST video
play head.
VPR-20 Internals