Preamplifier circuit diagram

Schematic diagrams for radio-frequency (r.f.) electronics are shown in Fig. 5.2. The circuit in Fig. 5.2(a) is a simple heterodyne circuit. The pulse length is defined by the switch SI. The speed of this switch determines the minimum pulse length, and hence the minimum lens focal length, and hence the highest frequency of the microscope thus the limit to the resolution is ultimately determined by the highest useful speed of this switch. S2 is the single-pole-double-throw (s.p.d.t.) switch, and Al the low-noise preamplifier. The mixer is a device that takes two inputs, the radio-frequency signal and the...

FIGURE 5. A schematic diagram of the electronic circuit required for a PSPC (1) source, (2) sample, (3) detector, (4) high-voltage supply, (5) preamplifiers, (6) shaping amplifiers, (7) crossover detectors, (8) variable delay, (9) TAC, (10) MCA. 

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