Pin Switch

Pin Switch Technique for Measuring Detonation Velocity. See Vol 3, C313-R to C319-L... 

Booster was used to initiate the expl at one end. The radial motion of the cylinder wall was measured in a plane perpendicular to the cylinder axis 7 inches from the booster end, A streak camera recorded the motion, using conventional shadowgraph technique (See under CAMERAS, HIGH-SPEED PHOTOGRAPHIC in Vol 2 of Encycl, p CI3-L). In addn, the deton velocity of the expl was measured by placing pin switches 9-i° apart on the surface of the cylinder, as described, for example, by Cook (Ref 2, p 29). The streak camera record was read on a precision comparator which punched out the data directly on IBM cards. A computer code con-... 

The use of ionization pins or pin switches in the measurement of detonation velocity was described in Vol 4, pp D632-638. Their principle of operation is the closure of an electric circuit by the ionization associated with a detonation wave. The latest pin switch techniques are described in Ref 11... 

In the ionization pin switch, two extremely thin strips of foil.(usually of silver), are placed between the increments of the explosive to test with the foil ends being separated by a gap, many times that of the largest grains of explosive (See fig) STAKON HOT LEAD... 

Pin switch signals are equally spaced at intervals of 7.33/x secs... 

Schematic View of Mottegang Apparatus Ionization Pin Switch Mechanical Pin Switch...

Pin Switch Arrangement for Granular Explosives Pin Switch Arrangement for Liquid Explosives Block Diagram of Raster-Generating Circuitry Sample Chronograph Record Pinset Diagram of Cook s Method... 

Timings (f) between the laser ignition (narrow) and the gating pulse for the PIN switch (shaded) to pulse the microwave (MW). In Exp. 1, the MW-width was typiccdly 50 ns. In Exps. 2 and 3, the MW-width was fixed to 20 ps. (Reproduced from Ref. [19] by permission from Springer Verlag KG)... 

Detonation velocities in confined charges may be measured with a streak camera or by pin switches. The techniques are potentially accurate to 0.5%. The camera has the advantage that a continuous record of buildup and detonation transfer can be obtained [18,19], In the sample holder (Figure 8), the central hole has the diameter of a typical detonator. 0.136 in. (0.345 cm), and the initiation of the lead azide is by a hot wire. The flat window, cut and polished from a 3/8-in. (0.095-cm) -diam rod, which covers the slit provides a bright, sharp slit image through which to view the propagation of detonation with the camera. 

A pin switch apparatus for use with lead azide is shown in Figure 9. The... 

Figure 1. Pulsed microwave Fourier transform spectrometer from 4 to 8 GHz.5 The numbers 1, 2, 3, and 4 designate the PIN-switches as described in the text. PD stands for phase detector and includes a phase locking system.

Figure 2. Pulse sequence for the PIN-switches 1 to 4 which produce a 10 nsec high-power microwave pulse and at the same time protect the detector during the pulse-on time.5 Each of the four pulses is approximately 1/isec long. The repetition rate for all four pulses is the period T. The triggering always occurs at the same phase of the incoming high frequency signal, but the number of cycles between the pulses is variable and determines T.

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