Mullard DDR100 accelerometer double diode

This valve measures 73x32mm overall and has an 8 pin Loctal base.

This valve is a double diode with the anodes elastically supported so that the anode impedance is varied when subjected to acceleration. When arranged in a bridge circuit the out-of-balance voltage produced by the variation in anode impedance is a linear function of the acceleration.

The frequency range over which the response to a sinusoidal acceleration can be considered independent of frequency is 0 to 250Hz.

Two details of the internal structure.