Radiological Survey Meter (Geiger Counter) CDV-715 Model 1A F9F Panther The knob rotates the barometric

The knob rotates the barometric pressure adjustment

This is an original WWII-era Course and Speed Calculator Mk II as used by aviators of the British RAF in its wooden case

It is essentially a flight computer as it provides the navigator with the integral calculators for heading

the position of a graduated card attached to the float is visible through a glass cover in the front of the bowl

shows evidence of this clock having been through NAS (Naval Air Station) Norfolk (VA)

Radiological Survey Meter (Geiger Counter) CDV-715 Model 1A F9F Panther The knob rotates the barometricHere is an authentic Geiger Counter as used by the US Civil Defense, plus original instructions. Operational condition accuracy is unknown. With a D cell battery installed, the meter needle activates when switched on.