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Mullard DDR100 accelerometer double diode

Size 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.

Heater voltage 6.3V
Heater current 600mA
Characteristics (in bridge circuit)  
Max anode voltage 10V
Max anode current 60mA
Max acceleration 100g
Resonant frequency 1kHz
Sensitivity (across bridge) 7.5mV/g


Bridge circuit

Inside view

Two details of the internal structure.

Inside view




Pin Function
1 Anode '
2 Heater
3 n/c
4 Anode '
5 Anode "
6 Cathode
7 Heater
8 Anode "

This file was last modified 15:15:59, Tuesday September 02, 2014