The final member of my former Clough-Brengle collection: a Model OM-A Frequency Modulated Oscillator, aka a wobbulator.
Here’s a view of the motor-driven wobbulator. The grill is the intake for the motor cooling fan.
The frequency scales reference this hand-calibrated chart.
A view of the wobbulator motor.
Note the spring-loaded split gears. This is a high-quality tuning mechanism.
The coil turret.
The turret contacts need a good cleaning!
Classic pre-war cloth-covered wire, with a careful rectilinear layout.
Note the laced cable.